I am sorry but any further derogatory comments about the noise in the background caused by the local lorikeet population will be deleted - I think we have all had enough of such comments. The noise is there and I can do nothing about it now for this video... Martin

@StandAloneAoi

5 жыл бұрын

I know nothing about this but it's fascinating! (What an age we live in every day is documentary day.) Your never going to get rid of those comments completely. But I was about comment as well just to ask what the noise was. Thought maybe you kept birds a hobby. If you edit in an verbal acknowledgment of the noise at the beginning it might get rid of some of those comments? Anyway, brilliant vid thanks! There must be so many younger people who are considering crafts they would have never remembered existed.

@flintknappingtools

5 жыл бұрын

ugg@stephen john gray

@StonyRC

5 жыл бұрын

Please don't try to obfuscate or delete the sound of the Lorikeets - they really do add to the video and they are part of your culture. That being said, this is a fascinating demonstration of casting and you've got the steadiest hands I've EVER seen - I'm a lifelong IT guy so this sort of engineering is completely foreign to me. Many thanks.

@crucifyrobinhood

5 жыл бұрын

Thank you Martin. Tbh I have some bad associations regarding large numbers of captive birds. Not ptsd level or "triggering" at all, just reminders of an icky situation. I'm glad I saw your comment before clicking off. I will watch the full video. It's not the chirping that was bothering me, just my own baggage and knowing those are just cutely annoying local hecklers changed my perspective completely.

@gullreefclub

5 жыл бұрын

Personally I find the sound of the Lorikeets squawking in the background quite charming and those that don’t like the sounds of Mother Nature in the background should do the world a favor and firmly grasp their lower lip with both hands and pull it over their head and swallow! Thanks for posting the videos my father and I both enjoy watching them very much.

Martin, Please disregard the negative comments. Make YOUR video. You have a skill that few, these days, have mastered. I enjoy your videos. If the Wife likes the birds, that is all that matters. You have to please her. You DON'T have to please us. :)

@olfoundryman8418

5 жыл бұрын

Just me, You are right, I sure have to please her😀. But as far as possible I would like to please my viewers too... Martin

I truly do enjoy our conversation it is nice to find someone with the technical knowledge and skills that you possess, you are truly one of a kind Martin

It's always a pleasure to watch you work

@olfoundryman8418

5 жыл бұрын

Jkay, Thanks for you comment. I take pleasure from knowing that you do the same... Martin

i like the wife helping and the birds sound great, learned more in this video then i did in 3 years in shop class !

@olfoundryman8418

5 жыл бұрын

Sgt, Thanks for your comment - I appreciate it. Must have been a bit of a slow shop class. 😏… Martin

I owned a cabinet shop and hired skilled masters. Some days I would just go out to the shop and watch the fluidity of some of these gentlemen's craft. Martin shows that same almost Zen grace. Cheers to you Martin.

@olfoundryman8418

5 жыл бұрын

Jim , You do me great honour! Thank you very much for your comment. It is comments like this that make it alll worth while...Martin

Amazing as always! It always blows me away that you so often get your parts straight from the molds with almost mirror finishes!

@olfoundryman8418

5 жыл бұрын

Shane, Thank you very much for your comment. Actually these parts did not need to have a very good finish as they get machined on much of the surface so I did not use my normal facing sand which is a fair part of what gives me a good finish. However in producing the "shine" the choice of alloy is important, of even greater importance is proper feeding - a poorly feed casting will look dull and in bad cases even sort of spongy. A fill as free from turbulence as possible is necessary too as is avoidance of unnecessary mould height... Martin

@smallcnclathes

5 жыл бұрын

I thought "come on he was not even trying to get a good finish, did not even use facing sand" but if you look at around 18.00 where the parts are still on the casting bench, the riser is reflected in the surface of the part. Not mirror perhaps but pretty good.

@KravchenkoAudioPerth

5 жыл бұрын

@@smallcnclathes PDG if you ask me! Mark

@smallcnclathes

5 жыл бұрын

Kravchenko Audio that is what I wanted to say but did not think of using letters to say it. Martin remelts parts that others would think were brilliant. Fortunately, he has the skill to keep up with his own very demanding standards. I have had him say to me ( as a customer ) "You can't have that, it is a reject" I was usually unable to see why it was rejected!

I love the juxtaposition of the ancient casting technology, aided by modern machining all to get a century old automobile back in service.

@olfoundryman8418

5 жыл бұрын

Dennis, I guess one does what one has to, to get the job done with what is to hand 😀 But you are right it is an interesting mix… Martin

@dennisp.2147

5 жыл бұрын

@@olfoundryman8418 No offense was meant by the adjective "ancient". It was merely an acknowledgement that, in this instance, the older technology is actually the correct technology to preform the task at hand, something that folks seem to forget in their haste to embrace the high-speed low-drag solutions which are quite often wasteful and produce a less robust product.

@olfoundryman8418

5 жыл бұрын

Dennis, Absolutely no offence taken at all - what you said was spot on... Martin

I do so enjoy watching a true craftsman at his trade! That is a fine helper you have there. Good ones are hard to come by these days. Mine's been with me for over 48 years! LOL Patiently waiting for part 2!

@olfoundryman8418

5 жыл бұрын

Mature, A fine helper indeed, 45 years in our case. Parts 2 and 3 in preparation... Martin

Brilliant video thank you. It’s great to hear your thoughts as you go (this is where I learn the most) you are obviously very knowledgable. A great watch cheers

@olfoundryman8418

5 жыл бұрын

Julian, That's why I prattle 😏 on so much! Glad that you liked it... Martin

Your "adjustable" flask system has given me some good ideas. Thanks for the video!

@olfoundryman8418

5 жыл бұрын

jarodeells My boxes, as you have probably figured, I made them! I have now close to 50 aluminium ones made over many years in 4 or 5 goes and I have been very glad of them as wooden boxes are - as I guess you know - the pits. The first two lots were of sand cast sides so for 10 boxes I had to do 80 sand castings - it took a while I can tell you! The last 20 or so boxes I gravity die cast the box sides - all 180 of them in one or two days! I currently have two videos in preparation. The first will cover my journey through moulding boxes over the last 50 years, what I tried, what worked, what didn't, what was good, what was bad etc. The second is derived form the first and is a design for what I think is a very versatile box suited to the hobbyist. It will be way more "adjustable" than what you saw here. In the video (maybe in a part 2) I will actually make a box using the minimum of equipment possible, basically a drill press is all that is really needed so anyone should be capable of making such a box provide they are prepared to put the effort in and as there are 8 sides to a box there is a fair bit of effort required. However currently I have a few holdups so these two videos are a month or three away yet - stay tuned.... Martin

Damn, the ol' chap is clearly not doing it for the first time. KZread is full of people bungling about with casting, but you don't often see vids from people who actually know what they are doing. Very nice indeed.

@olfoundryman8418

5 жыл бұрын

Aleksander. Thank you for your comment - I have had a few somewhat ordinary comments of late and I was feeling a bit down about it. You comment has given me a nice lift - thank you... Martin

@Mercmad

5 жыл бұрын

I agree. I watched foundrymen when serving my apprenticeship and you reminded me of a group of men long gone now ,who seemed to get everything done smartly ,without fuss and efficiently . Even watching you and your spouse with a proper handle pouring was interesting. I see drongos on YT using tongs, wet sand, not ramming , and so on but to see a tradesman ( in the old sense,not the ute driving yahoo of today) at work is a real pleasure!.

@rationalmartian

5 жыл бұрын

It is indeed. I'm an oldish engineer/fitter/mech, who did a real proper apprenticeship; the kind they rarely seem to do these days, in the UK at least. It is great to watch someone who is obviously a past master at something. It is pretty clear to anyone who does know, when someone else is a craftsman. One of the nicest compliments I ever had was from an old timer who worked at another dept down South, many years ago. Who stated that he'd been watching me, just sawing and filing, and how nice it was to see someone who obviously had been trained right and did it correctly. I do believe his exact words were, "address the job correctly" as in being stood and oriented correctly to facilitate correct true cutting. This is what comes to mind when I see other "old timers" practiced in these skills that seem to be overlooked and undervalued, also in danger of becoming forgotten skills, in our modern "progressive" countries. The only disapointment is having to wait for episode three. Bahhh!!! LOL.

@thebeststooge

5 жыл бұрын

Oh, yeah he is a master at this. Sure, even masters fail at times but try to replicate something he does and you too will see he has become a master at it over the years.

@stubbhub

5 жыл бұрын

I have watched so many of these casting videos on KZread and, my God, this man knows what he is doing. The efficiency of his work, the decisions he made - with clear justification, and the end result speak for themselves.

You truly are a master at these pours! You really care about every facet of the piece, and the quality instoled. Thanx for your attention to detail. :D

@olfoundryman8418

5 жыл бұрын

Captain, Thank you for your comment. I guess I am one of those "nutters" who likes to take a pride in his work. At time its rather a rod for ones back as almost Japanese like I strive for that unobtainable level of perfection - in a casting, huh - no chance, but that does not stop me trying... Martin

What an amazing helper you have;

@olfoundryman8418

5 жыл бұрын

Furness, Indeed I would be lost without her... Martin

Good on the old lady helping with the pour! Takes a certain bird to not only help with a pour, but get her end spot on. Bet it's not her first time holding the hot pot.

@olfoundryman8418

5 жыл бұрын

Car, No, indeed she has done it most capably for many years..Martin

I greatly enjoyed part 1 of the piston manufacturing, I have slight memories of the iron castings of pistons for the restoration of George Green's 1910 Brush back in around 1971 done at his Sydney home in Castlecrag. It was also the first car I learnt to drive with outside gear lever, handbrake etc. His 1910 Brush was different as it had the tubular radiator, it had been remade from the original found with the car.

The spirit of Burt Munroe lives! Thanks for sharing your process on this! There's a lot of experience you're not even saying outright that your hands tell to anyone watching carefully. Good on ya.

@olfoundryman8418

5 жыл бұрын

Car, Yes, the kiwi motorbike man, nice to be though of as having the same spirit as him ..😀 A lot of the old hands laugh at me too😏! Until they take a good look at my work!.. Martin

Thankfully your channel popped into my feed and now i am subscriber !!!! Love the birds !!!!

Great work, first video of yours I’ve watched, but won’t be the last - as mentioned by others, it’s good to watch someone that obviously knows what they’re doing. The detail and careful design of the mold is not something I’ve seen from other videos like this I’ve watched - it clearly shows the difference between a weekender and someone like yourself who’s obviously been doing this for decades. 👍😊

@olfoundryman8418

5 жыл бұрын

Phantom, I have had a few advantages over said weekenders. I am a qualified metallurgist who has studied everything foundry at every opportunity. I have worked in several foundries and have been making castings for over 60 years. . For 30 of which I supported the family (and the local bank!) I had to get good or starve - hunger is a great motivator. 😏… Martin

Thank you very much for the video, I have been a heavy equipment mechanic for 45 years now retired, I learnt a lot looking forward to the next one . I never knew you could cast pistons in sections, amazing work a real pleasure to watch . Did not even notice the bird song we have 2 Alex parrots and a sun conure combined they make more noise than all the birds you feed . Cheers from Australia Pete

@olfoundryman8418

5 жыл бұрын

Pete, Seems to be a bit of confusion here. Not casting the piston in sections, the bit already cast is a chill that will form part of the mould in which the pistons is cast - it will not be part of the eventual piston. Parts 3a and 3b to be released soon should clarify... Martin

@randomoldbloke

5 жыл бұрын

Thanks no longer confused

Excellent video, thanks for sharing your considerable skills.

@olfoundryman8418

5 жыл бұрын

Cwazy.. My pleasure... martin

great video, i look forward to watching more!

Good job, looking forward to parts 2 and 3.

@olfoundryman8418

5 жыл бұрын

Eddie, Part 2 should be about a week away, I am working on it now, part three, hopefully another week again.. Martin

Excellent job , i learnt something thanks for sharing

@olfoundryman8418

5 жыл бұрын

Mordi, My pleasure..

Haha help needed from the Mrs Martin eh, nothing like the womans touch!! keep up the good work. Graham.

@olfoundryman8418

5 жыл бұрын

Graham, Yep, I would lost without her - But don't tell her that😏.. Martin

As someone who works in a modern foundry, this was enjoyable!

@olfoundryman8418

5 жыл бұрын

Marko, Some say that modern foundries, with all their automation and robots, lack soul. Who am I to disagree 😏.I am glad that you enjoyed the video...Martin

Keeps coming up in my suggesteds, so thought I would have another look. Reasonable views! Started with an ad by the way.

Great new videos always enjoy watching.

@olfoundryman8418

5 жыл бұрын

Jamie, I am glad that you enjoy, thanks for your comment… Martin

Fascinating stuff! Love the birds too *;)*

@olfoundryman8418

5 жыл бұрын

Brodie, Your comment makes my wife and "her birds" happy, thank you... Martin

Well you grabbed our attention again! Can't wait for the next video.

@olfoundryman8418

5 жыл бұрын

Marty, Parts 2 and 3 in preparation should be out in order in one week and then another week. Nice to have your attention... Martin

Enjoyed the video, great information. Thanks again

@olfoundryman8418

5 жыл бұрын

Thomas, thank you for your comment. I am glad that you enjoyed it... Martin

Thanks, great information. Interesting way to gate round patterns.

@olfoundryman8418

5 жыл бұрын

Dan, Yes, its not an unreasonable way to gate round patterns not only does it (possibly) help with the separation of bubbles (and oxides in heavier alloys) but it also avoids turbulence that would be caused by going in radially as there is no impact on the opposite side of the cavity and reduced (I hope) vena-contract effects at the entry... Martin

@pvtimberfaller

5 жыл бұрын

I wonder if the chorials (sp) effect should dictate which direction you would gate from. Looks like you could have used a shaper for your chills, much faster than a tiny end mill.

@danharold3087

5 жыл бұрын

@@pvtimberfaller I hope you don't mind if I answer that. The coriolis effect which is due to the earths rotation is so weak it would be noise level at best compared the the forces at play.

Great episode Martin and very informative, can’t wait for the next two. Btw, hurry up, as I said, I can’t wait!

@olfoundryman8418

5 жыл бұрын

Mike, Patience my friend part 2 in a week part 3 two weeks, glad that you found it informative.. Martin

Great as always, Thanks for another lesson.

@olfoundryman8418

5 жыл бұрын

Jim, My pleasure... Martin

Super smart fella right there ! Thanks !

Very interesting, I love it!

Very interesting video! 👍

Very damn good job, top quality, as and having a helper such as that, even better. Lorikeets cool I have lovebirds and sun conures, and yes they do get loud at times but its only because they like the environment and love the mamas and the papas that take care of them. So you are blessed and the derogitorians are cursed, lol.:-)

@olfoundryman8418

5 жыл бұрын

Icinesis. Thank you... Martin

Looking good. Waiting for your next upload.

@olfoundryman8418

5 жыл бұрын

Brandon, Working on it!.. Martin

Your videos are always the most informative of any casting video makers - just amazing given you are working from a small foundry garage - I hope you recover the cost of all that effort because you are a real craftsman/artisan - but I suppose you would do a few love jobs.

@olfoundryman8418

5 жыл бұрын

Gez, Yep, love jobs - we all get caught with them. Sometimes its a good idea - I have a sort of "arrangement" with a tame patternmaker and we regularly do such jobs for each other, its an arrangement that seems to work well for the two of us. This piston is not a love job as I do get paid but to be honest not enough to really cover the effort involved. Usually I do reasonably well for my work but the years are making the physical effort increasingly hard! This is a young mans game!.. Martin

Looking forward to parts 2 and 3 as well. All ways learn something from your video's keep em coming!!

@olfoundryman8418

5 жыл бұрын

thehomefoundry, Part 2 you now have, part 3 - another week perhaps lot of editing to do! How goes your forum? I seem to get a funny message when I try to see it. And how goes your own casting?... Martin

@aonemarine

5 жыл бұрын

@@olfoundryman8418 Haven't been able to do much casting lately. Bought an old farmhouse that I've been fixing up. Just now starting to get moved in. Having a new shop 40' x 50' built in the next 3 weeks, then I'll be back at it. Fourm is doing well, still like to see you there :) that error that comes up is a https vs http. I need to sit down and fix that. You should be able to bypass it though??

@olfoundryman8418

5 жыл бұрын

thehomefoundry, 40 * 50 - Nice! Mine is 20*60 basically a brick four car garage so you will have a bit more room to move around in than I have. I will see if I can bypass that error and have a bit of a look see... Martin

@aonemarine

5 жыл бұрын

@@olfoundryman8418 join up. I think you would like the group I have there. Good guys that really enjoy casting. :) and would love to see you there.

@olfoundryman8418

5 жыл бұрын

thehomefoundry, Eh, still very much a case of once bitten twice shy I am afraid and I doubt I have the time available to be involved in a meaningful way and I know of no other way! I will look and lurk in the background for a bit at least... Martin

wow! what a great video. thank you so much.

@olfoundryman8418

5 жыл бұрын

Jimmy, Thank you for your comment... martin

The birds in the background are wonderful!!

@olfoundryman8418

5 жыл бұрын

bmcc12, Thanks mate, you have made my wife's day (and thus mine too of course 😀)… Martin

@Phantomthecat

5 жыл бұрын

bmcc12 agreed, they sound wonderful. 👍

@thebeststooge

5 жыл бұрын

I 100% agree. I have heard them before on his older videos and love it.

@johndowe7003

5 жыл бұрын

bloody annoying if you ask me.

@thebeststooge

5 жыл бұрын

Then stop watching and move on, snowflake.

Wow, now that's some crazy porosity in that old casting.

@olfoundryman8418

5 жыл бұрын

Ask, Yeh, and it was degassed too! Actually that casting was top poured (through an ceramic filter) into an oven dried mould. The piston was orientated crown up so the metal cast sat over and around the core. The alloy also had 0.02% strontium added to improve the silicon structure. Unfortunately the strontium can cause a metal mould reaction with moisture in the mould (the mould was dry but the core was not). This reaction generates a lot of hydrogen that all dissolves in the metal during and shortly after mould fill. The dried mould gave a very long (nearly 15 minutes!) solidification time, more than ample for any hydrogen present to come out of solution. In addition gases from the core (steam and air) seem to have not gone down out through the core but chose to rise up through the metal. The machining was only just a skim under the surface where typically the gas had collected, held for escaping into the mould by oxide film. This whole exercise was a learning experience and we very quickly learnt not to cast pistons this big in this orientation (I had earlier done much smaller pistons this way very effectively). To find that sort of thing in a casting is a sobering and humbling experience - a very potent reminder that none of us know everything and nor will we... Martin

@askquestionstrythings

5 жыл бұрын

@@olfoundryman8418 so true.

Great work as usual, thanks for all your info in these videos. I'd love to know more about the heat treatment part of the process after the quenching.

@olfoundryman8418

5 жыл бұрын

Walter, After the quenching I age the castings at 165 deg. C for 8 hours and then just allow to cool down naturally. Some times temperatures up to 205 deg. C are used. The only thing that you need for this is a fan forced oven - a domestic oven is quite suitable. However not all alloys will heat treat and you do have to know what alloy you are dealing with . I use 601 alloy (356 in the US) this is the wheel alloy. And scrap alloy wheels carefully cleaned, cut up, and melted are a good source if you can not get certified ingot as I do.. Martin

@walterszepesi2860

5 жыл бұрын

@@olfoundryman8418 Thanks Martin, I really appreciate the info. I have a lot of hard drives to melt down and as I can find info on them they're 308 or 333 alloys.

Well. off to see part two.

@olfoundryman8418

5 жыл бұрын

Pip, Enjoy... Martin

martin thanks alot for that book and the video it self .

@olfoundryman8418

3 жыл бұрын

sotode, I found the book an excellent starting point. There were a few errors regarding running the casting but they were easily allowed for. I am glad that you liked the video... Martin

Thanks for posting. I had no idea that the first pistons had to function without piston rings, but I guess it makes sense if you remember your little Cox .049 model plane engine. :)

@olfoundryman8418

5 жыл бұрын

Johnnie, I had one of those dastardly little engines too in a vacuum formed little trial guy wire plane. It never flew because I could never get the engine going 😥. However this piston does have rings as did the cast iron original that it replaced.. Martin

Beautiful car.

@olfoundryman8418

5 жыл бұрын

Stooge, Yes, it is a sweet little car… Martin

@thebeststooge

5 жыл бұрын

Back when automobiles had soul and class not press out of a mold.

@olfoundryman8418

5 жыл бұрын

Stooge, Indeed, how true... Martin

It was a Brush similar to this that first crossed Australia from west to east in 1910. Took about a month; Ferguson, Birtles and their dog. The Brush was largely made of wood and was chain drive.

@olfoundryman8418

5 жыл бұрын

Robert, Interesting. I will ask my customer what he knows of this. Apparently there are more Brush cars left in Australia than in the US - a local rally had 14 while the best in the Us was apparently just 11... Martin

@robertking3130

5 жыл бұрын

@@olfoundryman8418 There is book written by Warren Brown called "Francis Birtles", a stirring story of Australia's most unusual adventurer. Published by Hachette Australia in 2012, even printed in Australia. I got my copy through ebay. Birtles crisscrossed Australia by bicycle before embarking on his motor adventures and was the first to drive overland from London to Melbourne in the late 1920's. Truly worth a read by anyone about about one of Australia" unsung heroes.

@thephilpott2194

5 жыл бұрын

Yeah, i have that book. One chassis rail snapped and he had to retrace his steps to a woodcutter a few miles back, who cut him a new one so he could continue.

It was kind of scary at the point where you show the old piston castings. Memories of our Island prince of porosity were flooding in. Happily the rest of the video exorcised those bad memories. Martin you are one of the few people on KZread that I learn something from every time I watch your videos. Looking forward to the next two. This is going to be a treat in proper casting methods.

@olfoundryman8418

5 жыл бұрын

Mark, You thought it was scary! You should have seen my face when I took those trial cuts on that bad piston! It was the result of an initial casting try at making these pistons but so much gas came out of the core that it had no chance. In addition I had added some strontium to refine the structure of the alloy but this makes the alloy more susceptible to gas absorption not only during melting but also from the moisture in the moulding sand. Piston alloys are know to be prone to gas problems particular when cast in sand - it really is a gravity die casting alloy which is the way all but forged pistons are made. I do try to put something new in every video (I would not want you to get bored 😏) and usually if there is nothing new in a job I will not video it. If I have managed to pass information on to you then I am well pleased for that is my aim. Parts 2 and 3 are coming soon - I think that you will find the gating system used in part 3 quite interesting... Martin

@danielcrawford7315

5 жыл бұрын

@@olfoundryman8418 , thank you for sharing and allowing us to be bennifited by your experience. Have your considered using nickle/ copper alloying to reduce the grain size and gassing? Read a paper on it however I'll be 1st to admit I am not a metalurgist and not certain that it would fit your needs. As I recall the finest grain size and best performance of 760 NBA was achieved by adding 0.85% copper and 5.25% nickle. This seems to give great lubricity and greater wear and corrosion resistance, with all but no porocity. As I'm positive your much more familiar with alloys than I, I'm sure you understand the austinitic structure and the graphite forms. As per the paper the NI/CU alloying promotes the nickle carbiding and allows the graphite to become spherical in formation as opposed to forming in flames or sheeting. Maybe something to consider. As I said you know far more about it than I. So I hope this helps at least some

@danielcrawford7315

5 жыл бұрын

@@olfoundryman8418 , sorry shoulda gone back and undone spellcheck. Its mba... not NBA. Its flaking not flames. Sorry. Blessed days sirSir, Crawford out

@olfoundryman8418

5 жыл бұрын

Daniel, Perhaps I misunderstand but you seem to be talking, at least in part , about cast irons with reference to austenitic structure and graphite forms. However can you give me the title of that paper I would very much like to look it up and read it myself... Martin

@danielcrawford7315

5 жыл бұрын

@@olfoundryman8418 yes sirSir I'll see if I can find that out and forward it to you

You had me at "Casting".

Ok mate, I have a question about the feeder size. It doesn't appear that that much volume was required to handle shrinkage in the part. Was feeder that large, uh, tall, to keep it hot longer and thus to chill in a time commensurate with the part? Hi to Mrs Martin ;-)

@olfoundryman8418

5 жыл бұрын

Sw, Mrs. says Hi back! Casting was pretty thick and chunky, height was 32 mm, feeder height above that was about 103mm. Rough weight calculation gave both feeder and casting as about the same weight with the casting perhaps a little more. I have always liked to have yield around 50% but less when the casting is thick like this one - experience (sometimes painful, in the form of rejects) has taught me this. So in this case I was happy to accept a yield below the 50% (sprue basin runner etc enter into this yield calculation). I could have easily used a bigger in diameter but shorter feeder and it would have been slightly more thermally efficient but the height of the two little moulding boxes used together like this used is 135 mm so I just went with the flow. Note that I made no allowance for the effect of the chill on the feeding requirements. I could have, and maybe should have, as the effect would have been to reduce the feeder requirement probably by quite a good margin, but I am a belt and braces man and like the extra safety margin that the "over feeding" gave me. I was not worried about the height affecting the surface finish as it did not matter for this part, in fact I did not use any facing sand. I like to think that any extra turbulence coming from the 135mm total height (high for me as I think you know) would have been taken care of by the small sprue and pouring basin combination plus the tangential entry - Keep the last in mind for your future casting, its a useful trick.... Martin

@askquestionstrythings

5 жыл бұрын

Swdweeb if you want to get into the dirty details of the feeder/riser calculations the casting handbook has the equation in it. It's a function of volume and surface area. A cylinder is often used for the feeder/riser since the calculation and molding is simpler.

@olfoundryman8418

5 жыл бұрын

Ask, Sw, To be honest these days I just eyeball a pattern and take a guess at what is required in the way of feeder diameter then I structure the mould (i.e. use low mould extensions or not) so that the feeder is about 1.5 to 2 times in height that which it is in diameter. This is not hard and fast, if it gets to three times , eh, no biggie - more than that though and I would take action a larger diameter but lower height probably. I guess years of having done it and having dozens of different feeder formers on hand helps. I usually use cylindrical feeders as they are thermally more efficient (and easy to make in a lathe with any old bit of wood) than say square or oblong shaped, a sphere is the theoretical best but a bit awkward to work with. Any calculation if done would centre on the feeder being close (75 to 100%) to the same weight as the nett casting... Martin

I really don't understand people who complain about your birds, this is an instructional video showing a skill excellently executed using your time and your husbands and its FREE. Thank You. Your husband has obviously helped you before. I will be watching the rest of your vids and subscribe. As for the 43 dislikes what do these people want maybe it was your bolly wooly jumper. I did machine maintenance in a large factory that did high pressure die casting Ryobi and my HND in mechatronics included much to do with all types of casting so know the theory only. I guess there is a reason you didn't make the piston from billet aluminium?

@olfoundryman8418

5 жыл бұрын

Nightster, Its the old story - you can please all of the people all of the time. It does not matter what you do, there will always be people who will find something to dislike about it, It is perhaps a sad commentary on the times that we seem to be infested with a sub group of people who's only pleasure in life is complaining. Personally I think they need to get a life and until they do I will continue to ignore them and if appropriate delete their comments as is my ability and right as the owner of the channel… The why not billet is a common question and not an unreasonable one. I am planning to add a few minutes to part 3b of the video series to address that issue ..Martin

@nightster6378

5 жыл бұрын

@@olfoundryman8418 Thanks for the reply I look forward to watching it. I know even high performance piston today are not billet but dropped forged, Im not a fan of billet this billet that its very common in the motorcycling world and in most cases people wouldn't know as its difficult to tell after machined. I love the 1910 Brush (had to google it) my type of car, is it your own? I have a few old cars though mainly motorcycles but nothing as exotic.

@olfoundryman8418

5 жыл бұрын

Nightster, No, the car is not mine. I have neither the patience nor the money to restore such a vehicle. It is a sweet little car though isn't it... Martin

WOW, was wondering if someone had such online, I can tell you are a well trained much experienced craftsman, I was wondering how to make a cast, but would be willing to have one designed by a Pro as yourself, I'm looking for a cast that can handle a aluminum product for a home do it yourselfer

@olfoundryman8418

5 жыл бұрын

Numa, What is it that you actually wish to cast… Martin

Great work, beautiful castings, and interesting info as always! Can't wait for parts 2 and 3... Your comment about the stepped pouring basins having been used in the past but then falling out of favour reminded me of when I was recently browsing through the online version of the 1958 US Navy Foundry Manual (just a little light reading 😁) and was surprised to see a diagram of a pouring basin there that is not so different from the ultra modern type of stepped basin you are using. (Fig. 131 on the bottom of page 111 at www.hnsa.org/resources/manuals-documents/single-topic/foundry-manual/). Not exactly the same shape, but not really all that far off... The old navy manual also depicts many other pouring basins, often simple funnel shapes that you would disapprove of, but that one caught my eye immediately because of the similarity. I know it is an out of date resource and the info in it should be taken well salted, but I sometimes enjoy flipping through these old foundry books just to pass the time and see how things used to be done. Thought you might find that diagram interesting too. Thanks again for sharing your knowledge and experience, and keep up the great work! I know a lot of us hobbyists get pretty excited to see a new Olfoundryman video coming down the intertubes. With good reason. Edit - replaced the link originally posted, this one should work Jeff

@olfoundryman8418

5 жыл бұрын

Jeff, Yes, I to enjoy the old (and new) foundry books. I have rather a lot of them some very professional some amateur. Many are indeed out of date and in some cases downright dangerous to the production of good castings but many also contain old wisdom that is still valid today. The trick is to know the difference of course! Not always easy. I have a copy of the USN foundry manual and boy are some of those other basins shown of that page right disasters! But sadly we often see them in use on YT. Anyone using any of the basins shown in Fig 130 should have their box of matches taken away! And as for fig 127 (rightly shown as not recommended) not only do we have the worst basin imaginable atop a straight sprue but that form of gating results in all sorts of problems with circulatory metal flow soon establishing itself where metal goes in only through the bottom gate and OUT through the upper two gates! Thank you for your comment and I hope that there will be more videos. I have a few "in the can'' and ideas for lots more - so many in fact that I hardly know where to start! Sadly though I have spinal damage which has effected my balance and seems to make me extremely tired. Remedies have been undertaken but so far without a great deal of success, it may end my casting days. But even so I have a lot of video ideas that are of a more theoretical (but I think very useful) kind but I do not know how they will go down - time will tell... Martin

@tobhomott

5 жыл бұрын

@@olfoundryman8418 please take good care of yourself Martin. Best wishes.

Great video. Thanks

@olfoundryman8418

5 жыл бұрын

Rupert, Thanks for the comment... Martin

@ruperthartop7202

5 жыл бұрын

I'm setting my first small foundry so I am enjoying you videos

@olfoundryman8418

5 жыл бұрын

Rupert, Good luck with it. With persistence and patience it all slowly begins to work - keep at it... Martin

Thank you Martin, I'm very new to this and finding your videos immensely educational. You mention that "craft wood" (MDF in Canada) is not much good for making patterns...what would be a good wood to use? Thanks in advance, Al

@olfoundryman8418

5 жыл бұрын

Gippetos, Craft wood - we call it MDF too - has the failing that it is "furry" and a few coats of paint and some in-between sanding are required to "kill" the fur. Against that though is that it glues well and can thus be made into big lumps to make big patterns from. I do use it quite a lot for quick patterns where only a few castings are required off them. You should use a mask when working with it (I don't but I should!) as the dust is said to be cacogenic. Traditionally patterns were made from sugar pine as it is fine grained and works beautifully but it is now very hard and expensive to find. Most soft woods are too coarse grained and as there is a great hardness difference between the layers of grain it is a bit hard to work to get a smooth pattern. To be honest my pattern making skills are rather lacking and I tend to use a lot of car body filler to get things right. You could just try whatever local woods are available but to be honest enough paint and MDF is probably a good choice... Martin

Just to prove I watched it all. The exo was impressive, does the cross hatching show on the piston surface and when will you polish them thar ingots?

@olfoundryman8418

2 жыл бұрын

SmallCnc, Yes, the cross hatching does show on the as cast piston top surface, rather nicely in fact, and this can be seen in part 3. It is of course machined off - its only purpose is to ensure that the part of the piston cast against the chill forms properly. Polish the ingots, yeh - nah - not ever - not into turd polishing, better things to do with my time. Then again my ingots are not turds they are good metal!.. Martin

amazing

Absolute mad lad.

@olfoundryman8418

5 жыл бұрын

Paul, If you think that lot was a bit mad wait till you see part 3 😉 Thanks for your comment... Martin

an interesting video . Please could you tell me details of the heat treating done to the chill ? (ps I liked the birds.I am Half deaf and could hear you fine)

@olfoundryman8418

3 жыл бұрын

Anthony, My wife is very happy that you like the birds!😀 I used 8 hours at 165 C as the heat treatment for the chills which were cast from 356 alloy. The correct T5 HT for 356 is 8 hours at 225 Deg C. I only do the HT to improve the machinability and the lower temp seems to work OK for that but one day I will try the higher temp to see what difference it makes.... Martin

The flask or "boxes" appear to be cast metal as well. Very nice work, your friend in America swdweeb recommended your channel. You have a new subscriber.

@olfoundryman8418

5 жыл бұрын

Skully, Yes, the boxes are cast aluminium. I made them many years ago by gravity die casting the 160 or so sides that I needed in a day or two in a crude die I made from a continuously cast aluminium ingot. Bless Swdweeb!... Martin

Brilliant some people are so damn clever!!

@olfoundryman8418

5 жыл бұрын

Andrew, Its just a mater of practice - just like playing a guitar (which would love to do but cannot)… Martin

Great video martin! What alloy is used for a piston?

@olfoundryman8418

5 жыл бұрын

Mr greens, Thank you for your comment, The piston alloy is equivalent to SAE 336. Roughly its a 12% silicon alloy with an important pinch of each of copper nickel and magnesium. It is meant to be gravity die cast and is not really recommended for sand casting... Martin

1 awesome Lady you got there!

@olfoundryman8418

5 жыл бұрын

Old, I would be lost without her… Martin

Great video. Can't wait for the conclusion. As thick as that piston is I'm guessing there won't be any steel inserts as many cast auto pistons have?

@olfoundryman8418

5 жыл бұрын

Rambozo, Your guess is correct - absolutely no inserts at all, steel or otherwise. They are used I believe to help control expansion into certain directions enabling a tighter initial fit - along with other tricks like barrel shaped oval grinding and split skirts etc. This engine is just 10 hp. from the one 4 inch piston, compression ratio about 4 to 1 (wow, that high) and revs probably top out at less than 1000 rpm so we do not really have to worry about modern niceties 😏. The one I have already cast some months back is machined and fitted and the car is running very sweetly with it. The owner is very happy... Martin

whoa that is so cool :o

@olfoundryman8418

4 жыл бұрын

Atoool, Glad that you liked it…. Martin

Curious!!! Have you tried one of your pistons with that micro porosity / porosity. Does carbon not clog up the holes and “mature” the piston??? What do you think???

@olfoundryman8418

5 жыл бұрын

Alan, We could also argue that some micro porosity would hold a bit of oil and thus help with lubrication. In these days of high detergent oils clogging with carbon is a bit less likely. I know that with older engines (old stationary etc.) the use of non detergent oils is important as they seem to need the carbon build up to provide some sealing and with high detergent oils these old engines slobber oil everywhere and also burn lots of oil. This piston is of course for an old engine so you may well have a point. However, perhaps its the purest in me, but I prefer the most porosity free and strongest casting I can get- its sorta like the chase for the Holy Grail... Martin

Love the bird sounds

@olfoundryman8418

5 жыл бұрын

SmallCnc, So does my wife... martin

@smallcnclathes

5 жыл бұрын

And lets face it, an upset wife in the foundry is the last thing one would need! In the house ok, but not out there near the fiery furnace!

Really cool that you put in those comments like why you use a tangential runner. Why do you use parting powder in the riser and sprue?

@olfoundryman8418

5 жыл бұрын

Rotary, The parting powder in the sprue feeders etc is, I will admit, peculiar to me and probably me alone. Its a habit with me now. I do it because loose sand generated in further mould processing does not stick as much to surfaces coated with the parting powder. Thus I am able to easily blow and loose sand off these surfaces and out of the mould so it can not get dragged into the metal during the pour. In truth though providing a pour is not overly turbulent metal will run over loose sand rather than pick it up. Even so my theory is that it its out of the mould it can't get picked up!... Martin

@RotarySMP

5 жыл бұрын

Thanks for your response Martin. Your casting videos are by far the best on You tube, and the resulting quality of your castings show your experience. Thanks for taking the time to do them. I see you also use exothermal on all alluminium castings. I haven't tried to obtain any yet, but can't imagine a flammible magnesium mix being easy to obtain in small quantities for the hobbiest (at least here in Europe). On what sort of casting shapes is it strictly necessary, verses nice to add?

@olfoundryman8418

5 жыл бұрын

Rotary, I tend to use the exothermic on just about all castings except perhaps ones that are quite thin. The thicker and "chunkier' the casting and thus the bigger the feeder the greater the advantage of using the exothermic. You can get away with smaller feeders if exothermic is used and if you have limited ability to melt metal this is quite an advantage. I know that out here at least there are limitations as to how these exothermic materials may be transported - you can't post it for example and professional couriers need to be licenced to carry them. However you can go and pick them up from the supplier yourself (if you are close enough). If you can't find a supplier I suggest that you email "Foseco' they are based in the UK but are world wide, just ask them if they have an agent near you. The material comes in a 25 Kg bag should last a hobbyist for life! I can't quite remember what it cost - so don't hold me to this figure - but it was I think was about the equalivant of 4 Euro per Kg. Maybe you and some other hobbyists nearby can share a bag. Be sure to get one suited for non ferrous alloys as different formulations are used for different materials..Martin

@RotarySMP

5 жыл бұрын

Martin. Thanks for your response. Good idea. There is a foundry supplier in St Pölten, about an hour from Vienna who we got some oil based sand from. Mark

Hey Martin. I hope you are well. Its always astonishing to see how much casting sand fits into those "little" boxes. Thank you for the videos you upload, it's always a real pleasure to see a pro in action. About the heating of the steel plates. From the aluminium perspective the steel plates at 200°C seem rather cold. Would doubling it up to 400 being better in some way or is the possible benefit not worth the work? And what about heating up the molds itself prior to the casting? Another thing... about the safety of your wife you might want to start the pour the other way around so she is not exposed that much to the exothermic reaction of the pouder. I don't want to be a smartass. I was just a bit concerned about her safety here. And my last question. Would there be in regards to the flow a benefit to put in some rip-like structure around the casting to counter oxidation effects in the inner part? And as always can't wait to see more. :)

@olfoundryman8418

5 жыл бұрын

Han, I only heat the steel plates to make sure that they do not have any moisture or other volatiles on them. Later in part 3 when I actually cast the pistons against the chills made here in part 1 I do not heat the chills at all i.e. they are at rom temperature. I have at times use moulds that although not hot have been oven dried to remove the moisture from the sand. This has two effects firstly it allows the metal to flow into things like lettering on plaques - you get a very sharp fill of the mould the sharpness of the letters is amazing. Secondly it slows down solidification dramatically but this for work like these chills would not be a good thing and that porosity in the problem piston shown in the video is in part due to it being made in a dried mould and to the casting thus taking about 15 minutes to solidify -plenty of time for gas to enter the piston from the not dried and there for wet core and to come out of solution and grow to the bubbles we saw in it. Yes, you are right about the assistant being in the way of the exothermic fumes. However she seems to avoid most of the fumes and although they do get in ones line of sight there does not seem to be anything toxic in them - nothing that makes one hack and cough although unburnt bits of the exothermic do make one sneeze. Were we to pour the other way around I would be back handed and I would get the fumes 😏 However you have raised a legitimate issue, its just a question of what to do about it, perhaps I should consult he SMDS on the product to see what we are really dealing with. Now I am not sure what you mean by your last question, can you amplify please and I will try to answer.... Martin

Ok I was wondering what the bird sounds were I thought perhaps you had an aviary on the premises or near by. They sound very happy.

@olfoundryman8418

5 жыл бұрын

Terra, They are wild birds. They are Rainbow lorikeets and they turn up sometimes in the hundreds for a bit of a feed you can get a bit of a look at a few of them in this video kzread.info/dash/bejne/oaSfrpmyfbavY9Y.html They are feisty and noisy little fellas - my wife feeds them only a metre or three from where I make the moulds.... Martin

Could the aluminium chills be made from common aluminium (6061 or whatever) rod or plate? Or would this cause problems when the rest of the piston was cast on top of them?

@olfoundryman8418

5 жыл бұрын

Andrew, Yes they could, and I do not believe that it would cause a problem when the piston was cast as long as the chill was solid enough. The 601 (356) alloy I used is in the same family as 6061. I cast the chills because that's the way I make stuff 😏and because I did not have any plate or rod thick or big enough. Many foundries use cast iron or steel chills with great success... Martin

was the original piston in that motor even aluminum or could have it been iron or a different alloy of aluminum not like what they use nowadays. cause yea nowadays pretty much all pistons are made from molten aluminum rammed by a cylinder into a steel mold then the mold comes apart and drops it then goes back together for the next one. pistons these days in production are relatively cheep to make. its the piston rings that are relatively expensive to make

@olfoundryman8418

5 жыл бұрын

Flying. The original was cast iron - doubt there was much cast aluminium around in 1910. Doubt there would be too many iron foundries around who would do a few off piston these days., hence we went with aluminium in a modern piston alloy (336.) Most aluminium pistons are gravity diecast (Permanent mould) these days, a few are forged.. Martin

The missus is quite the shop hand, sir.

@olfoundryman8418

5 жыл бұрын

Edgar, Indeed sir she is. In fact I would be lost without her - a fact not lost on me 😏. She keeps asking me to cut her out of the videos but I explain that would be very difficult He He… Martin

Was that aluminium insert you used for turning the MDF? The result was not as furry as might have been expected.

@olfoundryman8418

5 жыл бұрын

Smallcnclathes. Tip was a Sumitomo SVGT AK This is a tip specifically for aluminium and has a 20 degree rake angle and an absolutely wickedly sharp ground edge. It is very handy for all sorts of work like this MDF turning where as you saw it produces quite a reasonable finish requiring much less sanding than the sort of finish that other tools might produce... Martin

Great video! What is the purpose of the exothermic powder and what are you using?

@pvtimberfaller

5 жыл бұрын

Slow the cooling of the metal in the riser so it will feed the casting & not pull a shrinkage hollow.

@olfoundryman8418

5 жыл бұрын

Bob, Ross is Right on... The answer I usually give to this question is - The exothermic catches fire and generates a lot of heat this keeps the feeder liquid for longer so it is better able to provide feed metal to the solidifying casting underneath. It is called "Ferrux NF" and it is made by "Foseco" … Martin

@MrEh5

5 жыл бұрын

@@olfoundryman8418 thanks for taking the time to answer my questions. Your videos are very good and informative.

is it possible to machine such piston from solid aluminum billet to avoid porosity issues? can you answer please, thank you sir, cheers.

@olfoundryman8418

5 жыл бұрын

electroganix. There is a series of comments with DjjC13 that go into this question . It has now been asked /suggested several times so I will address it near the end of the last part of this video series... Martin

What is the purpose of the "exothermic"? Thank you for the video. BTW I love the sound of the lorikeets!

@olfoundryman8418

5 жыл бұрын

Bruce, The powder that I put on top of the feeders immediately after I have poured is an exothermic called "Ferrux NF" it is made by "Foseco". It catches fire and generates a lot of heat. This keeps the metal in the feeders liquid for longer so they are better able to provide liquid feed metal to the solidifying casting underneath. Yes, it is like thermite, but I do not know exactly what is in it for it is a propriety product. But I would guess at some iron oxide from the colour and no doubt some sort of metal powder. There is also something in it that expands when heated to form an insulator... Martin

@brucewilliams6292

5 жыл бұрын

@@olfoundryman8418 Thank you very much Martin. I can see how keeping the sprue liquid longer would help a great deal, especially for larger castings. Merry Christmas.

I liked the birds actually

@olfoundryman8418

5 жыл бұрын

Glide, It is surprising how many people did, more did than did not. Thank you for saying so... Martin

Is there something mixed with the sand to keep it from crumbling back into the cavity?.....Hal

@olfoundryman8418

5 жыл бұрын

Hal, This is a so called "green" sand, as such it contains a fair bit of clay, the addition of some water makes the clay sticky it is this that holds the sand grains together and stops the rammed sand from crumbling back into the cavity... Martin

Jeez that rings a bell- is the Brush not the type of car that Francis Birtles used for some of his early expeditions in the never-never?

@olfoundryman8418

5 жыл бұрын

Philpott, Apparently according to Robert King in his comment you bell rings true!... Martin

Cool car! Just curious why if the original pistons were cast iron, you chose to cast the replacements out of aluminum?

@olfoundryman8418

5 жыл бұрын

Lost, Yes originals were cast iron. Hard to get a foundry to make a few iron pistons these days but pattern maker knew a foundry who would make aluminium ones - me!... Martin

You should of gotten the late great Burt Munro to cast the pistons for you!

@olfoundryman8418

5 жыл бұрын

Andrew, Much more fun to do it myself..Martin

War Grade, Please note that this video was shot before you were kind enough to send me the Loctite 😀… Martin

@WarGrade

5 жыл бұрын

PMSL My comment was to be "No comment". On a note of a recent conversation we had regarding shrinkage porosity, your photos confirm our thoughts, they show the outer wall's are excellent and inner bad. The exterior cooling first preventing any negative formations & the porosity getting worse toward the last part to chill (for any one reading this, that last bit to chill might not always be the thickest of the centre depending on what you are casting). I do like the hatching you put on your chills Martin, almost all modern pistons have this on the inside as do many cylinder-heads and the like (never considered why), for ever learning. Talk soon mate.

I like them liar birds.

please can one use only your type of facing sand for casting

Great Video, are you able to sell a finished Brush Piston? I have Three of the little cars and one could use a new piston and rings

@olfoundryman8418

7 ай бұрын

Kleps, Its a bit complicated! I made these to order for a local Brush owner. (Strangely perhaps there are said to be more extant Brush cars here in Australia than in the US and Canada) I used his patterns so I am not able to ethically make one or sell one for to anyone else. Unfortunately my health is now such that I am no longer able to make any castings and that situation may improve or may not. I was supposed to make 7 pistons but only got 3 done before the health issues stopped me. I do have one complete piston here but it is a first try and proof machining has shown the casting has a fair bit of fine gas throughout it. Considering the low loads and speeds in the end use this may not matter all that much and at a pinch it would probably do but I would disown the casting as its not up to my standards. However, obviously I can not let you have this piston unless we get the ok from the local brush owner. Incidentally he may have one of the 3 pistons that I did make available and in any case may well be planning on having another foundry make the required four more. He has also had Brush blocks cast and probably still has these for sale too. I do not have his contact details but I am in contact with the patternmaker who organized it all (he helped me make the castings too) and if you come to me at olfoundryman@gmail.com with an email address I will forward your info and request to him and no doubt he will onforward it to the local Brush owner..... Martin

@KlepsGarage

7 ай бұрын

Thank you. I will email you when I get to my office. Will be your nite time. I don’t half to have a piston. Just thought you might have casted a few extra. Good luck on your health. God bless.

Would Lost Wax & plaster, ceramic slurry + sand work better than sand?

@olfoundryman8418

5 жыл бұрын

Peter, Depends on in which way you mean better. Well done such an investment process would yield a more size accurate and well finished casting. However the slower solidification rate inherent in investment work could (would?) lead to significant more problems with both shrinkage and gas porosity. Also a coarser grain structure would result - not good for the optimum mechanical properties. This alloy does not really like being sand cast it prefers the higher solidification rates inherent in gravity die work. On balance I would say sand better gravity die best (by far)… Martin

May I kindly ask the name of the substance you use for exothermic? THANKS:

@olfoundryman8418

5 жыл бұрын

Hasan, The exothermic I use is called "Ferrux NF" it is made by "Foseco". Most foundry supply houses will have an equalivant, just be sure to ask for an exothermic that suits the metal you are casting... Martin

What is your aluminum alloy mix, and also what are you using for exothermic in the past I've tried injecting dry nitrogen to push the O2 from the melt but ended up with other issues any ideas

@olfoundryman8418

5 жыл бұрын

M&M, I buy certified ingot, locally its called 601 but in the US its known as 356. Nitrogen will not "push O2" from the melt unfortunately just about nothing will remove oxygen from aluminium melts such is the rapacious appetite that Aluminium has from oxygen. Nitrogen (or argon which is what I use) will "push"(absorb) hydrogen from aluminium melts but it needs to be bubbled through the aluminium with the finest possible size to be effective.... Martin

@mmheavyconstruction3148

5 жыл бұрын

@@olfoundryman8418 I tried using sintered stainless steel exhaust ports designed for use a pneumatic muffler such as like in use with pneumatic motors in harsh environments they are 0.25 inch ID x 0.35 inch OD x 2.343 L now the last batch of "nozzles" I was able to procure silicon carbide sponge ceramic tubes with a measurement of 3.000 inch OD x ?ID x 0.348 T with a silicon carbide ceramic taper fitting of which I plan to machine tapered bushings of graphite and fit them to custom flared stainless steel tubing as a means to inject several different types of gasses some of which will be mixes in an effort to remove as much oxygen and hydrogen as possible from the gas phase transfer of opening the Liquid propane jet kiln to pouring also of note I reconfigured my kiln such that the walls are part of the lid which Also open like a hinge from the sides, It sounds overly designed and less conducive to production which it is but it allows me to explore high temperature or for lack of better words super heated gas injection process which does not interfere with pre cooling the melt thus allowing smaller diameter sprue and waste gate columns, it is just purely expensive experimental casting at it's not so finest, at this point I have an even amount Success's vs. Complete Failures

@olfoundryman8418

5 жыл бұрын

M&, this al sounds rather interesting, It would be good to see a video of it al happening… Martin

@mmheavyconstruction3148

5 жыл бұрын

@@olfoundryman8418 as soon as I get a chance I will upload the Ver.6 Liq propane furnace, I have to recast the floor as I hammered it out to accommodate a preheating coil for the Liquid Propane and also cool the floor at the same time as well as a piping well for the flushing gas piping to get in without having to use KAO-wool 5000 as a. Gasket (I do wear a remote air supplied respirator and negative pressure fire hood as a precaution for the unknown and the Kao-wool hooks that are airborne in the blast and opening procedure. Although the KAO-WOOL hooks will no longer be an issue as will the over air charging as a result I still will wear the pressurized respirator and negative pressure fire hood which is rated for 6700° F melt contact at 30 min burn through as well as the rest of my PPE, I use this overkill PPE Protocol because of the nature of what I am attempting to do.

@olfoundryman8418

5 жыл бұрын

M&M The powder that I put on top of the feeders immediately after I have poured is an exothermic called "Ferrux NF" it is made by "Foseco". It catches fire and generates a lot of heat. This keeps the metal in the feeders liquid for longer so they are better able to provide liquid feed metal to the solidifying casting underneath. It is like thermite, but I do not know exactly what is in it for it is a propriety product. But I would guess at some iron oxide from the colour and no doubt some sort of metal powder. There is also something in it that expands when heated to form an insulator... Martin

Since you have a lathe why not cast the piston with 3-5 mm extra on the top and then turn it down for a nice clean surface?

@olfoundryman8418

5 жыл бұрын

Noah, That is exactly what happens although its only 1 to 2 mm extra. That "problem" piston that I showed would not have been as bad 3 to 5 mm down but it was still too bad to use... Martin

They look like lapping plates. Not sure why the chill plates stop porosity but it's hard to argue with success.

@olfoundryman8418

5 жыл бұрын

Rv4, The chills have two effects, First they ensure rapid solidification, this gives a finer structure and a much smaller bubble size if any gas does come out of solution - usually though with chills the solidification is so rapid that even if there is a lot of gas in the metal it will not have time to come out of solution and form bubbles. Second the chill sets up a strong thermal gradient between itself and the feeder (assuming both are properly placed.) Steep thermal gradients encourage better feeding and thus less shrinkage porosity. As a third effect the finer structure seems very much to produce a better looking machined surface finish... Martin

@sblack48

5 жыл бұрын

Thank you. Very informative.

Hi! Sorry, my English is bad, did I understand correctly, you said that the pores in the casting of the cylinder appeared during casting, due to the gas evolution of the central core of the mold, which forms a void in the center of the cylinder? This seems unlikely, the saturation of the melt with hydrogen does not occur so quickly. More like melting without purging and flux. With a lack of flux, about a third of the metal mirror was not covered with flux, I had smaller pores without any purging with argon. The pores were opened only when sanding with sandpaper 200. I have not worked with cores yet, but in our literature, cores are recommended to be dried at a temperature of 200-250 Celsius, sandy silicate cores, I have not heard about others in Russia yet. Thank you for your work, very interesting.

@olfoundryman8418

5 жыл бұрын

Dmitriy, Much to discuss and explain here! That piston shown in the video with the "problems" was an early effort. It was cast crown up using a central large feeder (not unlike, but bigger than, the feeder used on the chill cast in this video) A ceramic filter was placed in the bottom of the feeder and the metal introduced into the side of the feeder just above the filter from there it ran down through the filter and down into the cavity. I have used this gating technique quite successfully on a few other castings but only ones much lower than the 125 mm height of the piston, so we knew we were taking a bit of a risk but we wanted to provide feed directly to the heavy crown of the piston. The metal had a small addition of strontium to refine the silicon structure and the mould (but not the core) had been oven dried at about 150 deg. c for some hours. Unfortunately the strontium has the additional effect that it somehow modifies the permeability and reactivity of the natural oxide layer on the molten aluminium. This allows much easier penetration of water vapour and thus the generation of hydrogen gas within the liquid metal. You get a metal mould reaction and the castings come out looking a dull burnt grey rather than then usual shiny bright surface I normally get. This grey surface is a certain sign of the reaction and inevitably there will be a lot of gas in the metal, commonly but not only, concentrated just under the skin. Even though the mould was oven dried it will still contain much water as the drying will only drive off free water, that bound with the clay in the sand will only come free with higher temperatures - say, when the hot metal hits the sand. So there is water around to cause the formation of hydrogen. The core contains a lot of water and later in part 3 of this video you can see the steam and water coming out the back end of the core. Poured the way this "problem" casting was steam from the core bubbled up through the metal and became trapped under the oxide skin against the sand at the top of the cavity. Some of this steam will have reacted to form hydrogen within the metal and here there was more than enough time for this to occur as I know that the casting took 15 minutes to go solid completely (dry moulds cool very slowly!) This is way longer than needed to generate quite a lot of hydrogen by bubbling steam through the molten aluminium which is exactly what happened. In addition I believe that air between the sand grains of the core will have expanded due to the heat of the metal and it too bubbled up through the metal and became trapped just under the top skin of the casting. Note that the vertical sides of the piston were much freer of gas - just some very fine bubbles like you describe and this despite the grey appearance indicating the reaction as above. Note that the machined surface you are looking at is only about 0.5 mm below the as cast surface so it shows all the gas - of whoever source - that got trapped just under the skin, another mm or so down most of that would not be there. I might add that piston alloys are know to be "difficult" when it comes to gas - they absorb It readily when molten and expel it all to easily when they solidify. They are normally permanent mould cast where solidification rates are much, much faster and gas does not have time to come out of solution as much as it does in sand casting. The metal was both fluxed (Foseco coverall 11) and degassed (with fine bubbles of argon) I know that some core making processes -particularly the older ones based on "core oils" do require oven baking at around the 200 deg. c mark but I have not heard of it being done to silicate CO2 cores - does not mean it can't be though. Most if not all hobbyists would have the sort of porosity that you are finding (or worse - a lot worse). Most likely they never see it as their castings being un heat treated will machine badly and the tools will smear over the fine porosity. A quick etch with NaOH solution will reveal al sorts of problems!😏 To sum up this "problem" piston was cast the wrong way (in Oh so many ways 😏) In part 3 we cast it the way it should be 😀 so, please, stay tuned... Martin

@dmitriykolesnik4462

5 жыл бұрын

I did not know about strontium. Then it looks like saturation with hydrogen, 15 minutes in close contact with the steam thats probably enough. However, there was no passing of steam through the metal, with active boiling the metal foams, and you did not have a layer of foam, the 0.5 mm allowance is a jewelry job. But 15 minutes is really long, and hydrogen is really fast :) I found a description of the three ways of preparing silicate cores: exposure to air, blowing CO2 and drying in a oven at 200 degrees. Unfortunately, no details. Thanks for the answer, waiting for the next video :)

@olfoundryman8418

5 жыл бұрын

Dmitry, I did not notice any boiling or frothing when I poured this piston but the exothermic added on top immediately after pouring would have made it hard to see. However I think that rather than a boiling of steam right through the metal it was more of a surface reaction and absorption (thanks to the strontium). The 0.5 mm removal was a deliberate small cut to see what was just under the surface as I knew that is where the gas etc would be at its worst. There was in fact a machining allowance of about 2mm on the casting. I just wanted to see how bad things were. The long time is quite clearly indicated by the size of the gas porosity in the central section which was directly under the feeder - bubbles that big take some time to grow. I learnt a lot with this early piston casting - How not to do it! The eventual results as achieved in then upcoming part three are much, much, much better. Any of those methods for silicate core should work but note that as rammed these cores have almost no strength - they are just like damp sand at the beach. Thus while uncured they are difficult to handle and if cured out of the mould need to be self supporting and that assumes that you can get them out of the mould in one piece while uncured - very difficult. You can of course gas them with CO2 while in the mould, everybody does! But you can not either air dry or oven dry in the mould. It is perhaps a bit of an unfortunate inconvenience that such an easy core making process really needs a cylinder of CO2... Martin

Why exothermic powder added only on top of the feeder?

@olfoundryman8418

5 жыл бұрын

MZero The powder that I put on top of the feeders immediately after I have poured is an exothermic called "Ferrux NF" it is made by "Foseco". It catches fire and generates a lot of heat. This keeps the metal in the feeders liquid for longer so they are better able to provide liquid feed metal to the solidifying casting underneath. It is like thermite, but I do not know exactly what is in it for it is a propriety product...

What is the exothermic topping you placed on top of the feeder?

@olfoundryman8418

5 жыл бұрын

Donald, It is called "Ferrux NF" it is made by Foseco other foundry supply companies would no doubt have an equalivant ...Martin

@donaldasayers

5 жыл бұрын

@@olfoundryman8418 Thanks for taking the time to reply to my questions. Cheers.

Apart from cooling so as not to get burned, why do you quench? I am sure getting burned is not a reason.

@olfoundryman8418

5 жыл бұрын

Smallcnclathes, The quench locks alloying elements (magnesium and some silicon in this alloy) in solution in the aluminium. This improves the response to later ageing heat treatment during which these elements come out of solution as billions of very small precipitates perhaps only a few hundred atoms across. These impede movement of dislocations within the alloy - dislocation movement is the way in which metals deform and restricting dislocation movement improves hardness, strength, and thus machinability. The difference in the latter can be dramatic, from machining chewing gum to machining something that chips reasonably well and finishes nicely as you saw with these castings... Martin

@smallcnclathes

5 жыл бұрын

Wow, I did debate whether I should ask or not, now I know. So the long explanation is: This is a very necessary precursor to heat treatment which improves machinability?

Top section = crown.

@olfoundryman8418

5 жыл бұрын

Graeme, Indeed, you are quite correct... Martin

What is the powder for antioxidation that you pu at casting?

@olfoundryman8418

5 жыл бұрын

RedRock, I assume that you mean the powder I put on the top of the feeder immediately after pouring. It is an exothermic compound called "Ferrux NF" made by "Foseco'. Its job is to catch fire and generate a lot of heat which helps keep the feeders liquid for longer so they are better able to provide liquid feed metal to the casting underneath - the ash left after this "fire" dies down does act as an insulator.... Martin Reply ·

@redrockpixels8864

5 жыл бұрын

@@olfoundryman8418 Thanks a lot for the information that is what I mean.