Once again another informative video. The fact that you illustrate failures makes us have a connection to you. All the best my friend!

@cncnutz

6 жыл бұрын

Thanks Mick

Here it is 1 1/2 years later and I just found this video. Thanks for posting it. My first thought on a fix for the leak is to laminate a piece of Formica (which I have). Sealing it with paint or other sealers sounds much easier though.

Great video Peter gonna watch the progress keep them coming.

@cncnutz

6 жыл бұрын

Thanks, will do.

Stumbled on your channel last night while making some adjustments to my dust collection system. I appreciate how informative your videos are, fascinating bit here about the vacuum traveling through the MDF itself - I would've never been able to diagnose that! Will file that info away if I attempt this project in the future.

@cncnutz

4 жыл бұрын

Thanks Christopher

Thanks for sharing! ...yeah - MDF is super porous, I use it quite a bit as scrificial material on my (aluminium) vacuum table. especially when I want to mill some alignment pockets into it. Generally I prefer kork because it does not leave a burr as MDF does when milling through. the fact that you found it gets more porous overt time is surprising though! thanks again for sharing!

I just built myself a small vacuum hold down table and very impressed with it. I have found especially for smaller pieces putting some "none slip grip liner" under it helps a lot. I used plywood and created the holes just part drilling 3mm holes (around 3mm deep) then after this going over again with a 0.8mm drill this time going right through (spaced at 1cm).

@cncnutz

2 жыл бұрын

Sounds great. With MDF you probably don't need to drill the tiny holes as I discovered ion my 2nd build. MDF is so porous. Cheers Peter

Hi Peter, first seal the bottom plate with varnish or paint on the top side (where the vacuum channels are cut), seal everything, including the sides of the channels. Second, close the channels by putting a plate on it and put vacuum on it, then start "painting" white wood glue on the sides of the bottom plate while under vacuum. The vacuum will suck the glue in and help to close every little pore. repeat if necessary until vacuum holds. Check also the down side of the bottom plate (with the "smoke detector") and apply glue there if needed. Let it dry overnight and it should be ok for use. By the way, the vacuum you're using will not last long for this purpose, the motor will quick enough overheat and that's it then. I speak out of experience here ;-). I have build a perfect and cheap vacuum pump out of a standard compressor, with a buffer tank and automatic switch on and off to keep the vacuum nice at the requested level. It works like a dream and can not only be used for vacuum laminating veneers and making your own plywood, a vacuum forming machine but also for a vacuum table on the CNC. It has a cycle time of 30 seconds on and 4 minutes 30 seconds off. Keeps the compressor motor nice and cool! Also, saves on the electricity bill. Similar vacuum systems are sold for at least US $ 1,200 and up, it costed me less than US $ 200 including a couple of vacuum bags! Maybe an idea for a video series about it? ;-)

@rptrower

6 жыл бұрын

I also lost a vacuum cleaner motor due to overheating. I bought as used hvac vacuum pump to replace it. I'm going to add a buffer tank as you did. I glued a thin sheet of plexiglass to the bottom of my mdf plate then used white wood glue to seal the rest of the area. I use small sheet of plexi to block off areas not need when routing.

@cncnutz

6 жыл бұрын

Thanks for the writeup Paul. Great information and sound advice. I has wondered how well the vacuum would hold up over time. I don't think I will be using it a lot but if I do I will look into a proper vacuum pump. I've seen them made from old fridge compressors as well. Cheers Peter

@cncnutz

6 жыл бұрын

An Hvac pump would be a good idea. Better than the fridge pump I've seen used by others in the past. Something to consider for sure. Cheers Peter

@loskop100

6 жыл бұрын

I make custom hold downs for engraving perspex. I gave up on vacuums because the reduced airflow robs the motor of cooling and use a $99 ebay vac pump with an out of date bbq gas bottle for a tank. I use old 35mm counter tops for the hold down and just router v grooves in it so it looks like a block of Cadburys and drill a hole into the edge and connect to a vertical hole down from the one of the v grooves. It doesn't look anywhere near as impressive as yours but they do hold well particularly on smaller pieces ( 150x150 on up) even for doing the final profile cut. Using old counter tops or the sink cut outs on new ones means that the bottom is already sealed and only needs the side sealed with PVA.

@cncnutz

6 жыл бұрын

Thanks Loslop I will have a look for a cheap pump on ebay. I hadn't bothered because I thought they would be really expensive but maybe it isn't. Now if you will excuse me I'm off to buy some Cadbury chocolate. Cheers Peter

Hi Peter, nice work , that will be my next project.

@cncnutz

5 жыл бұрын

Thanks Max.

Good plan, and yes MDF is very porous, as some have commented sealing all non vacuum areas is a fix. I would like to suggest a future project, make a radius support for that poor dust vacuum hose in your background, it’s about to be strangled, LOL

@cncnutz

6 жыл бұрын

Great Idea Hager. Never thought of that but I do feel guilty every time I see it hanging there. It is now in my list. Cheers Peter

For the very interesting video. It was also very informative. I particularly liked the large vacuum pockets with the small vacuum holes to provide strong vacuum force with very little leak when the hole is not covered. Very clever. I'm currently building a vacuum table for a CNC router and I'm using high-density polyethylene as the base where the channels are routed and I will place a thin sheet of particle board on top as a sacrificial spoil board and I am planning on using the porosity of the particle board as a feature in my vacuum table as opposed to a problem. I'll know later today if it worked. :-)

@cncnutz

6 жыл бұрын

Thanks, hope the table works well for you. The HDPE will solve the base problem I experienced. If you can't get enough pull through the MDF you could try skimming the hard surface off the back to make it even more porous. Cheers Peter

@Liberty4Ever

6 жыл бұрын

I'm planning to use particle board as a cheaper and more porous spoil board than MDF, and I'm planning on removing the top and bottom surfaces to increase the porosity. I'm cutting 24 inch by 48 inch sheets of plastic. My biggest concern is that the kerfs around all of the small parts will allow enough air to enter the vacuum system that my 1/8 HP diaphragm vacuum pump won't be able to maintain vacuum pressure. I may need a higher volume vacuum pump, and maybe a professional shop vac with a TEFC motor that can be run for hours at a time without burning up the motor pulling a static vacuum load when there isn't enough bypass air for motor cooling.

very interesting and informative thank you for that

@cncnutz

6 жыл бұрын

Thanks Bernie

Another masterpiece!

@cncnutz

6 жыл бұрын

I don't know about that at the moment but hopefully when it is finished.

@pwrouzaud

6 жыл бұрын

Actually, I was referring to the overall video; I learned a lot. BTW, seems to me with the small drill holes opening into larger chambers, an absolutely air impervious material (like HDPE) would be the ticket. Thanks

@cncnutz

6 жыл бұрын

Thanks Peter.

From what I have heard, paint the MDF with 1/2 PVA glue and 1/2 water. This will seal most of the issues. Include the sides of the MDF.

@cncnutz

6 жыл бұрын

Thanks

@mrkookalabanza

3 жыл бұрын

I solved my issues by taping the edges of the spoil board.

Nutz...do u think particle board would be similar to mdf ..allowing air through it?

I would love to know how this comes out moving forward. Being a dustmaster myself, I seem to make it and nothing cleans it up for me! I would love to have something like this for my many projects! I can't wait to see what you come up with as far as problem solving this issue.

@cncnutz

6 жыл бұрын

Thanks Tracy. Paint seems to be the most popular idea in the comments. Cheers Peter

Do you have the dimensions of the vacuum table and how deep you mill and what is the raster size you use , maybe a smal drwaing so i can make it also. Maybe you have a dxf svg file ?

You are welcome Peter! Yes, you do have to seal the MDF :) virtual any spray on poly or watered down PVA glue will do (amongst others).

@jordanfelipe402

6 жыл бұрын

Agreed. Spar urethane is what I usually use. It's really easy to apply if you get it in a spray can.

@cncnutz

6 жыл бұрын

Thanks Jordan.

@cncnutz

6 жыл бұрын

Thanks.

Dear Peter, Please use several coats of spry clear or paint onto the surface and closeup the sides as well with thicker brush on paint like latex, color is not important. As always a very good job done thanks for your energy and time to show your work. Robert

@cncnutz

6 жыл бұрын

Thanks Robert

What model vacuum are you using for this?

Pete Is this your secret "Almost Useless Challenge" entry ? :-) Great project once you get it sealed. Cheers Rob

@cncnutz

6 жыл бұрын

It probably qualifies for sure. Cheers Peter

Hola, tengo una pregunta: a la mesa de vacio se le puede poner encima una lamina delgada de aluminio o cobre y hacer el vacio?

Another option (if you wanted to use something other than MDF, is to use a bench top product called CORIAN. It is a plasticized wood product (from my understanding) which machines beautifully. I have used it to make molds for producing RC aircraft parts. It is sealed (hence its use in bench tops), and off cuts can be sourced from a bench top supplier (if you ask nicely and provide choc biscuits... ) Only issue is it only comes in 12 mm thick, but can be glued together (with epoxy) to get a thicker section. Keep up the great video's Cheers

@cncnutz

6 жыл бұрын

Unfortunately I have not found a source of Corian here. I'm not even sure it is used in New Zealand but thanks for the thought. Cheers Peter

@andrewniles5390

6 жыл бұрын

Hi Peter, it is, im in palmerston north, can put you in touch with a supplier if you liked.

Peter, Ted Gauthier of the Michigan CNC group made a vacuum table very similar to your except he used melamine board to cut the vacuum channels into. He then used a .5 thick piece of MDF as the spoilboard after skimming off the outer layers of the MDF. The vacuum passes thru the spoilboard holding down the piece to be machined. He uses a Fein vacuum unit.

@cncnutz

6 жыл бұрын

Thanks Jim. Malamine is something I have been thinking about a a good material for the base as it's surfaces would be well sealed to start with. Our need to seal the edges. Cheers Peter

@jimsinacola-totallywoodwor7473

6 жыл бұрын

Melamine here in the states is sealed on all sides, top, bottom, edges.

@jimsinacola-totallywoodwor7473

6 жыл бұрын

in the above Ted cut a groove around the vacuum grid 1/4 x 1/4 and used a gasket material to seal the edges. All of the vacuum grooves were cut the same. His vacuum was attached in the middle of the board underneath going through his CNC bed. I can't do that since my Gatton is sitting on a table. I was already looking into something you were doing, bringing the vacuum in from the top.

It would be interesting to try making the layer with the channels out of a sealed board (eg formply) and just using 6, 9 12, 15 or 18mm MDF above the channel layer to see if the vacuum created is sufficient to hold some material on top of the MDF. How did you calculate the depth and width of the channels - same as the cross sectional area of the hose nozzle? Cheers and thanks for the demo.

@cncnutz

6 жыл бұрын

You got it. The hose area then made sure the area of the channels were bigger. This experience has opened my eyes to the power of even a small vacuum. Cheers Peter

I'm going to do something similar when I get my 4'x8' machine except the slot panel will be 1" PVC and the panel above 1/2" PVC with 1/4" holes.

I was watching another video on a different topic and it was mentioned that mdf was porous. I thought the glue would seal it. Thanks and I can't wait to see how you solve the problem. Maybe epoxy?

@cncnutz

6 жыл бұрын

Thanks Grant.

@drmkiwi

6 жыл бұрын

Yep, PVA definitely seals the MDF (I've only done this around the edges of the MDF, but it increased the amount of hold down significantly. Cheers, David.

Woow incredible, I have idea. Maybe you should try using varnish from bottom side to stop vacuum loss, and after that resurface top. Maybe that will work.

@cncnutz

6 жыл бұрын

Thanks Majsta.

Hey peter how about a few layers of paint to seal the bottom of the mdf?

@cncnutz

6 жыл бұрын

That should do the trick. Cheers Peter

We use MDF spoil boards for our vacuum tables at work. MDF is very porous and needs to be sealed everyplace you do not want vacuum pulled. All edges must be painted with several coats of paint or with wood glue, we actually edgeband our table tops. Even if you leave the hard glaze on the MDF it will pull vacuum through it. I would be curious to see if you made a spoil board with no holes in it, if it would pull enough of a vacuum for your parts. For our industrial machines, there are no holes in the MDF, the vacuum is pulled right through the 3/4" board after a light skimming to remove the glaze and to roughen the surface for better friction between the table and the parts being machined.

@cncnutz

5 жыл бұрын

It might be fun to just screw a vacuum hose into a piece of MDF and see how good a vacuum table it is. It certainly seem to be porous enough even with a vacuum cleaner. Or am I just being silly? Cheers Peter

@genecollier576

4 жыл бұрын

@@cncnutz Here in the States we can get what is called "MDF lite" that is even more porous than plan MDF and is used as a spoil board.

nice idea , i would make the top plate remove able so you can de-clog it should a channel fill with wood dust the vacuum cleaner might get hot if you leave iton too long , you might want to keep an eye on that maibe if you paint or stick a sheet of plastic under the surface it will seal it

@cncnutz

6 жыл бұрын

The top plate screws down for that reason and so it can be replaced when it gets to the end of its like. The vacuum issue is something I am looking into. Cheers Peter

why did you choose to go with the peg board hole style of board rather than the grid style that some others use?

@cncnutz

4 жыл бұрын

Grid style is for oring use. My holes are for vacuum. I'm not sure if they are really needed but they look good. Cheers Peter

How about using Formica as a backer sheet, or take advantage of that vacuum, for both sides. Hardwood could be your friend

MDF is porous. We use a solid MDF for Wasteboard because the Work piece will get sucked down by the Solid Wasteboard. Spray the chamber with epoxy or eurathane coat until its sealed or use a resin / plastic chamber.

seal the mdf with 2 or 3 coats of a good oil base paint. A good check on the seal is to do a sample peice and toss it in a pail of water for a week or so. i the mdf dosent change size, you got it sealed. if it starts fallig apart, it isnt sealed. I nfact my homemade cnc is ALL well sealed 3/4 mdf. The rest is somewhat the same as yours, v- rollers running on angle iron and lead screws. Havent seen any issues with it in several years. Its seriously heavy but no problems whatsoever pausing around a good 30 pounds or so of it with 450/oz steppers with 5 start 10 pitch half inch acme rods. :) Makes for some sweet smooth 300 ipm rapids with a surprisingly rapid acceleration too..

@cncnutz

6 жыл бұрын

Thanks John. Sounds like a nice machine you have there.

You could try using yacht varnish as it super strong and will never go porous also it stops most of the humidity if any. to cover any unused parts of the table try some closed cell neoprene. foam

@cncnutz

5 жыл бұрын

Good idea about the varnish though the acrylic paint is holding up fine at the moment. That could change over time. Covering the unused hole doesn't make much difference unless the piece is small due to the small hole size. Thanks for the neoprebe idea. I think I have some laying about. Cheers Peter

Just for anybody finding this we have industrial cnc units and we use varnished board 👍

Hi Peter, yes so much of what I do is trial and error as well. Forgive me if you have covered this already, but I wonder if you are aware of any time out function or setting in Mach3, where if you bring in your code, get everything zeroed, then for what ever reason you don't touch the machine for maybe 20min, the steppers become non responsive but Mach3 still seems to function as normal. Reboot Mach3 and things are ok again. No big deal but a bit irritating. I have a router controlled by a G540 and a mill with a Homann BOB and G213v on each axis. Any ideas? Cheers Phill

@cncnutz

6 жыл бұрын

Nothing that I am aware of. It shouldn't be doing that. I am curious what you are using to connect the pc to the drives. Are you using the parallel port or a motion controller? Cheers Peter

@phillhinkler3174

6 жыл бұрын

CNCnutz (Peter Passuello) Thanks for your reply Peter. I'm using a parallel cable on both machines and a Dell Optiplex 755 pc.

@cncnutz

6 жыл бұрын

Other than making sure you have things like screen savers turned off and power settings set to keep everything turned on I can't think of anything else. It sounds like the issue is your PC is going into some kind of sleep mode. I used to run a program called RM clock on my laptop to make sure the processor didn't reduce power while in use because laptop try and conserve power. RMclock can keep processors runing at full speed even when not in use stoppng them from going into power saving mode by slowing down. It's possible your PC has the same type of function. It may even be a BIOS setting cpu.rightmark.org/products/rmclock.shtml Give it a try and let me know if it fixes the issue. Cheers Peter

@phillhinkler3174

6 жыл бұрын

CNCnutz (Peter Passuello) Thanks Peter I will Check that out as soon as I can. Getting my eyes upgraded with new lenses at the moment.

I presume this table is only used for material that you are not going to cut through completely or do you use it to hold a sacrificial surface to which the material to be cut is affixed?

@cncnutz

4 жыл бұрын

No I cut all the way through the material and don't use a sacrificial board. Cheers Peter

@paulreader1777

4 жыл бұрын

@@cncnutz Thanks Peter, How often do you have to resurface or replace the top of your vacuum table?

@cncnutz

4 жыл бұрын

@@paulreader1777 I have only used it 5 times before my vacuum hose broke. So far there isn't a mark on it. The thickness of the paper between the stock and board is enough clearance so far. I will be building an upgraded model before too long I hope. Just looking for a suitable vacuum. Cheers Peter

@paulreader1777

4 жыл бұрын

@@cncnutz Thanks again Peter I am probably going to try building one for our shared Men's Shed machine will let you know how we get on

Many examples of vacuum boards I have seen made of MDF, they use a finish to seal the MDF. I would expect several coats of polyurethane would do the job. The only concern I would have is the level of the board after absorbing the finish. I would put a couple coats of polyurethane on and then resurface bottom and top of the board and then repeat. Make sure you apply the finish to the edges also, but they don't need to be resurfaced just lightly sanded to knock down the fuzz. I wonder if using HDPE would be better? I've seen scrap pieces at my local supplier that are close to the dimensions you are using.

@FreemanPascal

6 жыл бұрын

Another thing I have seen done is to have the board under vacuum when applying the sealer. This causes the finish to be pulled deeper into the MDF.

@cncnutz

6 жыл бұрын

Thanks

@cncnutz

6 жыл бұрын

Thanks Freeman.

MDF is actually used as waste board on top of vacuum tables on large carpentry Cnc machines. So do not use MDF to construct the vacuum table but use flat MDF as waste board on top of your vacuum table. Also if you block the air through the vacuummachine you might blow it's thermal fuse. normally vacuum machines use the filtered air from the hose to cool the motor as well.

@cncnutz

6 жыл бұрын

Thanks Henrik

@maximumiq158

6 жыл бұрын

if you also mill a thin layer off the MDF then it becomes even more transparent to air flow.

filmed my first halftone photo its uploaded

Perhaps use the mdf piece to create a mold and cast something that's non-porous.

Just us a non porous material for the bottom. No sealing required. Acrylic would be perfect. How do you calculate the airflow? I need to make a removable 2x4 vacuum table

@cncnutz

5 жыл бұрын

Hi Joe I don't know about air flow but I simply calculated the cross section aeea of the hose and made sure the cross section area of the galleries was equal or greater so it didn't restrict air flow. Cheers Peter

@joezcorvette

5 жыл бұрын

Thanks peter that makes perfect sense. Great video. I have watched it many times over 1st and second episode. I am trying to understand why the holes on the spoil board? I understand that it is to pull a quicker vacuum, but if MDF or LDF is already porous. Why make any holes? As long as you mill off both sides of the mdf to remove that flat hard compressed material. Kind of like the next episode when you use the newspaper trick. Thanks buddy! Live, eat, sleep CNC! Keep up the great work.

@cncnutz

5 жыл бұрын

In all honesty Joe I thought holes were needed when I made this and will be doing as you suggest when I do my rebuild as I was thinking the same thing. I also want to test holding with pockets machined into the top against no pockets and see it there is any real difference. Cheers Peter

think ill give the vac table a try . i wonder if sealing it with a rubber coating mite fix the issue

@cncnutz

6 жыл бұрын

Just beware that others have warned the vacuum cleaner my burn out if run like I am using it because of the loss of air flow through it. It is something I will be investigating. Cheers Peter

@23fields

6 жыл бұрын

i found this old hand pump with a hose on it you pump it and it creates a strong vacuum im thinking about making something with that i just got to see how well it holds stuff

@23fields

6 жыл бұрын

it appears to be old bike tire pump with the check ball valve reversed i was told it makes 11lbs per square inch of suction not sure if that will do or not

What keeps vacuum from heating up under load and burning up motor

@cncnutz

3 жыл бұрын

Choosing the right vacuum with independent cooling.

Nutz i posted link earlier ....look a couple messages down....i actually was given a store bought vac table for free.. Its 14x24 made by vacuum table co based where u r in uk.... Its made of 2 pieces the top is 1/4 aluminium and bottom is made of some type of plastic..its about 1/2 thick....and then has many tiny holes on top and has 4 inlet holes on side

@cncnutz

5 жыл бұрын

Thanks I see it now. I answered the previous post from my phone and it didn't show me the rest of the comments. Thats a great table and it makes we wonder if adding a series of shallow holes into the surface of the spoilboard would help vacuum as well. Thanks for the link. I will be doing a bit of thinking about that. I don;t know about partical board but I would be tempred to use melamine MDF which will definately be sealed on the faces and then some edge banding to seal the sides. Oh man, as if I didn't hae enough projects. 😉 New video out later today all going well using my vacuum table. Cheers Peter

Goodonya mate great video right

@cncnutz

3 жыл бұрын

Thanks 👍

nutz here is the link for the guy that used mdf as a passthrough for mounting his material...i thought it was magic lol

Can you make a video of how you made the table in the software and maybe share the files?

@cncnutz

5 жыл бұрын

Hi David, If you email me I can share the files with you but I am now seriously considering designing a newer, simpler build hopefully without the previous issues. Use the link on my webpage to contact me. Cheers Peter

Good video. I am thinking about using a vacuum pump instead off a vacuum cleaner. Less noise and might be cheaper to operate. I have sealed my mdf with paint which done the job on the vacuum leaks.

@cncnutz

6 жыл бұрын

Thanks John.

@servant74

6 жыл бұрын

As long as your pump can do the volume. A vac table needs very little pressure or volume normally, the volume is needed when the table is not sealed fully. Lots of luck with your system!

@cncnutz

6 жыл бұрын

I agree. Volume is needed to comer the leaks in the system and a little vacuum goes a long way if spread out over a large area. Cheers Peter

Just paint the whole unit. Sprayed rubber seal works well too.

@cncnutz

6 жыл бұрын

Thanks Impyman

you can seal the bottom and edge or use another material the air can't go from it you really be amazed from results ^_^

@cncnutz

6 жыл бұрын

Thanks Mostafa

When you mention that the vacuum will overload when it spins faster, it is really being under loaded. The motor spins faster because it has less load when you plug the air input, as it creates less dense air around the turbine, and motor uses less power. From electrical point of view, less current. Now, maybe bearings might not be up to the task of that little extra increase in speed, but it is less 1.5x extra.

@cncnutz

5 жыл бұрын

Thanks Ivan for pointing out the vacuum spins faster. I confess that I never noticed it. I would hear the change of pitch but not thought about it any more than that. It's amazing how you don't notice or put 2 and 2 together but when it is pointed out it is obvious. That said the reason the vacuum burns out isn't the bearings, it's the heat. Because it is not 100% efficient much of the power going into the vacuum is output as heat and without the air flowing through it will overheat and burn the windings. Cheers Peter

@keithfisk5641

4 жыл бұрын

​@@cncnutz Industrial or "shop vacs" are available with a bypass air passage so that the vacuum suction pipe can be blocked without blocking the motor cooling air supply. Household type vacuum cleaners that rely on the exiting air to cool the motor are not much use for dust extraction and vacuum tables in the workshop as invariably there are situations where the air flow is restricted. A good vacuum cleaner will have over temperature protection but a not so good one will burn out. Cheers Keith

Hey nutz lookmat this vac table video...the guy just uses mdf as,spoil board and the part holds throught the mdf....apparently mdf allows air through it..like magic

@cncnutz

5 жыл бұрын

Hi der ddd That's how commercial vacuum tables work and seeing how porous mdf really is now that I have tried it I'm no longer surprised. I'm not seeing the link you are referring to. Can you repost it. Cheers Peter

Seal with shellac should do the trick

@cncnutz

6 жыл бұрын

Thanks Robert.

the last project that sucked i done was the dust boot for my cnc

@SmoggyTurnip

6 жыл бұрын

Does this mean that even if you had a perfectly sealed table you still wouldn't be able to hold MDF to it?

@cncnutz

6 жыл бұрын

Well so long as it didn't blow. 😉

@cncnutz

6 жыл бұрын

I think the vacuum would still bull through the sides of the MDF and unless the base pulled down to the table top hard I think you would still loose preasure that way. sealing is the only answer for the MDF base.

@taranson3057

6 жыл бұрын

Industrial cnc routers do not use MDF they actually use low density fiber board. You can make the bottom portion out of cast acrylic or you can coat the MDF with lacquer or a fast dry wood hardener. Your project is spot on just needs a little bit of help.

You cannot have dozens of large open holes and still have a vacuum. It's like trying to put a voltage across a short circuit. Why don't you have a cover mechanism for blocking the holes you don't need for a job.

@cncnutz

5 жыл бұрын

Hi Lindsay, You are right. Even uncover 1 large hole and the vacuum will disappear and that is why there are no large holes in my vacuum table. I can have up to 25% of the ports uncover and the part will stay put. I admit that covering unused holes will help keep better vacuum but it will still work even if I don't. Cheers Peter

You could use HDPE. LeRoy

@cncnutz

6 жыл бұрын

It would be nice and air tight and ideal for a small unit. Cheers Peter

@servant74

6 жыл бұрын

HDPE would be great. MDF is lower $$ solution, especially good if it isn't a $$ making endeavor.

You have to seal the sides and faces of your mdf!

@cncnutz

6 жыл бұрын

Thanks Julius, I think I've figured that bit out. 😉 I am just surprised that something like a vacuum cleaner has enough suck to do that to MDF. Cheers Peter

@urgamecshk

6 жыл бұрын

CNCnutz (Peter Passuello) i want a vac table but the only job i'd use it on takes over an hour so double sided tape seems cheaper in the long run

@cncnutz

6 жыл бұрын

I just want to hold thin material flat while machining. It's always a pain when it bows. I thought of using tape but have always wanted to try a vacuum. I agree about the cost of running the vacuum. Cheers Peter

@Regnarrussell

6 жыл бұрын

Mythbusters lifted an entire car with just a shop vacuum. kzread.info/dash/bejne/eZalrdmJm9eplNI.html

@cncnutz

6 жыл бұрын

It is incredible what a simple vacuum can do.

its compressed sawdust. its not glued. its not a solid chunk of wood (which is also fibrous) you need to use a sheet of plastic or aluminum. its solid and not porous.

@cncnutz

5 жыл бұрын

You will see in part 2 that I painted it which seems to have sealed it quite well and adds plastic seal to the bottom well for an added seal. In hindsight making the bottom from a plastic material would have been a better idea but you live and learn. Cheers Peter

@RozetRides

5 жыл бұрын

CNCnutz (Peter Passuello) true story. I’m a machinist for a living and we have special suction plates built specifically for certain jobs and their profiles. We do however have different sub plates that are more universal. They have one hole in the center and the o ring we use can be orientated o fit the profile of the part. The vacuum pumps we use can be controlled on the amount of vacuum actually applied to the fixture dependent on tool pressure and material. Sometimes we can use flooded coolant and sometimes we have to use forced air. Again thanks for the videos and being so involved with the audience.

Methinks this is overkill on holes, and a wee bit of under-engineering. A measure of spring-loaded marbles.... scaled to measure with CFM of your vacuum .... divided by the area of the vacuum table..... Think ... Pressure is Vacuum. Table Area Needed Hold Force CFM Value. Tooling Forces Applied. Estimate your required information carefully. Do you ABSOLUTELY NEED FULL TABLE VACUUM ? Does your machine process only a single few shapes ? Palletized processing could change EVERYTHING. Palletized means much can be diversified. Merely adding FOUR OR SIX HOLES... for 4 or 6 + pallets... May negate some resources at some point in the process. Each "HOLE" can be electified, pneumatic, or hydraulic optioned. Yes ? No ? Shape your VACUUM Table to each specific part.... is efficiency.

Yes a lot of people find this hard to understand. My pump pulls through 25mm mdf that has been skimmed both side with the edges sealed. You may not need all of the holes 19mm just try a sheets of mdf and mask off the area that you are not using with a plastic sheet

@cncnutz

6 жыл бұрын

Thanks

@drmkiwi

6 жыл бұрын

Yep, plastic sheet does wonders, but a big PITA when the hold down vacuum is exceeded by the dust extractor and the sheet tears away! I've scavenged off cuts from builders wrap and other packaging. Cheers, David

Woodprix has very good and accurate plans.

my power supply took a crap on my cnc

@cncnutz

6 жыл бұрын

Sorry to hear that. Really annoying.

@23fields

6 жыл бұрын

i got it all worked out

Fiberglass.

@cncnutz

5 жыл бұрын

Fibreglass would seal it for sure Gordom. Let the resin soak into the MDF and it will never leak. Cheers Petre