I make those little earthenware Roman oil lamps, soaking in vegetable oil then baking in the oven at 4 or 500 degrees like cast iron pans. seems to seal them and give a glossy glazed look glazed look.

@AncientPottery

2 жыл бұрын

Excellent method, thanks.

@torsteinraaby

Жыл бұрын

Thank you!

@TrueFork

Жыл бұрын

for how long did you bake?

@lucasrafe0

11 ай бұрын

What oil do you use? Soy oil should work?

I recently had great success using powdered skim milk to seal a couple small drinking cups. I like using powered milk for a couple reason. 1. It is fat free and it's my general understanding that it is the proteins that bond with the clay to do the sealing. 2. It stores indefinitely if stored well in its dry form. 3. Its often cheaper than standard carton milk 4. You can mix as much or as little as you need (I made mine with double the powered called for in the directions. What I did for a process was find a plastic container with a lid that would hold my pieces and made enough milk to cover the pieces. I allowed them to stay in the milk over night in my refrigerator with the lid on the container. I then removed the pieces and removed all excess milk with a cloth and paper towel (mine had a thin white slime on there surfaces before wiping. I then placed them in my oven starting low around 200 degrees for a while to dry them. (Same as you would if you we're preheating greenware) Then I brought the temp up to say 300 for 20 min or so. Then up to 450-500 which is the max for my oven. Held this high temp for 15-30min then turned off the oven and allowed to cool. In my case I repeated this process because I didn't feel a had a complete seal after the first soak and bake. I was happy after the second time. My pieces changed color from orange to a couple different shades of brown but are now completely sealed and water beads right off. They have no noticeable smell. This might not be perfect for decorated pieces but worked very well for what I intended.

@alyxlessthan3

2 жыл бұрын

I have also done as an experiment this exact same process but used olive oil instead of milk. I have a very well sealed pot that has a shiny black layer of carbon on it much like the lay a cast iron pan would take from being properly seasoned. Maybe next time I would try to only treat the inside of my pot as I'm not sure If having that layer on the outside would be a fire hazard or not. But the one I tested was just for show and testing purposes anyways.

@AncientPottery

2 жыл бұрын

Awesome, thanks for sharing you process. I think powdered milk sounds like a great solution.

@AncientPottery

2 жыл бұрын

Also olive oil would work well, I am currently working on that for my little oil lamp.

@shaunhall960

Жыл бұрын

Nice! I will try using the powdered milk.

In Slavic area, we had a tradition of sealing / tempering with żur, zhur soup, made of lactofermented rye. Is it any known in the US?

@AncientPottery

2 жыл бұрын

Interesting, I have never heard of that. But I just looked up the recipe and it looks interesting, maybe a future video?

@mmlearner

2 жыл бұрын

Curious. I wonder about how the history of fermenting works with this? Sourkraut sealed vessel? Hmm

Good change in the audio quality. Rewatched it for the sake of the algorithm... The denaturation of the milk proteins reminds me of casein based paints :)

@AncientPottery

2 жыл бұрын

Thanks for re-watching. Yes, this could be similar science, I don't understand the science of the process well enough to say for sure.

To make a water-resistant paint I combine casein with quicklime putty (aged at least 70 month). It's been uses for millenia to make adhesive and binders. Ones quicklime dries it turns into limestone again.

@AncientPottery

Жыл бұрын

Cool, thanks for the tip

maybe it's good to mention that people should put the pot into a COLD oven to start with and then let them both heat up. Loved seeing this, Andy. And if you were making a mug with the milk seal, there wouldn't be any residue left after because you drink your tea or coffee faster.

@AncientPottery

2 жыл бұрын

I guess it depends the person and speed that they drink. Good tip too, thanks

If it's the protein in the milk, then you should try a sealing with milk based protein shake/supplement powder.

@AncientPottery

2 жыл бұрын

There's an idea, thanks.

Hi there Andy, interesting channel! About sealing and milk sealing in particular. I do some reenactment and historical crafts. In my opinion pottery have historically been sealed in different ways according to what the purpose the vessel will have. What it is suppose to keep. For drinking water I would use beeswax or any combo with beeswax. seed oil I think needs to oxidize, wish take longer time, as when you make an oil cloth. then one will hang it in the sun to dry and "harden" for weeks... I got a tip from another history geek who is a potter about milk sealing for keeping oil... She told me to let is soak in milk and keep the "residue" layer after emptying it. Then just set it aside and let it sour for a long time. (like months) then it should be fine. I haven't tested this yet myself. Keep up the good work

I've read from some potters that you can just use yogurt or a slurry to coat the pot as an alternative to soaking. Additionally, some say just putting several coats on the surface is enough to make a seal.. Since you're not trying to "glue" a cracked item. Additonally, it seems like the reason the dairy works is due to the caisen protein.

@AncientPottery

2 жыл бұрын

That's a new one on me, but sounds like an interesting experiment.

@mrscotchguy

2 жыл бұрын

@@AncientPottery I was doing some research for a pot that developed crazing lines. I used. This process with coffee to reseal the crazing lines and dye them as well to my them more visible. It worked surprisingly well.

Thank you for this and all your videos. May I suggest in when evaluating a seal in future you try weighing your pots before and after filling to show how much is soaking into the pot?

@AncientPottery

2 жыл бұрын

That's a great idea, thanks!

This is really educative! In Tibetan earthenware milk sealing is done just after the firing, while the pots are still hot, you can check out the video if you look for "Fire and Earth - The Tibetan Blackware Pottery". By the way, I tried firing black ware inside two barbecue lids put together into the fire so that the pots are practically sealed from the smoke except for two small holes were the handles were, and covered it up with sand once the fire was at its best. The pots came out all black although here there was arguably no smudging, so I suppose there is a deal of reduction and smudging if you only cover the pots with sand. Also it is important that the fire burns on while you have covered it by sand, and that the wood doesn't fall down. Perhaps reduction and smudging come generally hand in hand unless you can isolate the pots from the fire as I did with the double barbecue-lid. If you try out the barbecue lids be carefull to put a little sand into the one under the pots or the black paint of the barbecue might stick to the pots as it did happened to me. Balint

@AncientPottery

2 жыл бұрын

Thanks for the tips here. I have never tried firing in a barbecue but with the amount of questions I get about it, I should.

@petrapetrakoliou8979

2 жыл бұрын

Alternatively you can just put stones into the barbecue lid on the bottom just as you do in the direct fire so if they get sticky the stones will stick not the pots. I also use barbecue lids as "cover sherds" in bigger firings - it seems in this coastal part of northern Sweden there is always wind so I really need to cover the pots well and don't yet have many ceramic cover sherds to use, but have started to make some, thanks to your video about it!

The use of milk immediately makes me think of galalith. It was the go to plastic before the development of petroleum based plastic. It was used to make things like buttons. It's very simple to make at home with just milk and vinegar. The commercially produced galalith was soaked in formaldehyde which made it extra hard. But the homemade stuff is still plenty strong. I think I'll try experimenting!

I wonder if this is the same as milk paint and sealant. The casein protein is coagulated from the milk with an acid then reacted with a base turns it into a glue that is watered down and pigments are added to make paint. Plain milk, preferably skim milk, can be sprayed onto things as a sealant for artwork/wall paint and it is waterproof/resistant as long as the protein layer remains intact. Some people say there is a sour smell as these products dry but that it goes away after some time. The one time I used milk paint I didn't notice a smell. Idk about heating this up. I wonder also if eggs (which would be expensive but if you had a bunch of them from your chickens and they were going bad, you might as well use them) could be used. Egg yolks are also used as paint and are waterproof/resistant once dry but I doubt you could heat this up since proteins denature with heat.

It may be a year, but I believe that instead of "soaking it" maybe how about submerging it in milk? It's not my area of expertise however I believe it's the perfect way of truly saturating the vessel. Excellent work by the way, for some reason I'm hooked on your channel. Don't know if it's your voice, your train of thought, your chillness or just how good you are at making pottery but I really love your videos. Keep up the good work.

@mrq6270

3 ай бұрын

I was thinking the same thing. I recently watched a video of someone who made beautiful ocarinas. She dipped them in milk before firing, just like you would with a glaze. The clay was white and the end product was a lovely dark brown shade.

The fats will convert over to a secondary polymer from the milk fat similar to cast iron sesoning sealing. It's why you dont wanna burn it since that will destroy any plastic type polymers created. I'd strongly reccomend using a more controlled method of heating to do this sealing to help convert everything and drive of the agents that can sour since that smell is typically caused by bacteria we can determine your milk soured during the process at some point.

@America_Yea

9 ай бұрын

Which actually makes whole milk a whole lot better for this in my own testing and research you can get just as much effectiveness as glazes for long term water holding from proper temperature contol and a secondary layer made of thin oil seasoning.

@America_Yea

9 ай бұрын

You can avoid the milk souring before firing by keeping the pot refridgerated during the soak then using a freeze dryer to dry your pot or baking it quickly out at 200 till dry before moving over to the heat. It's highly likely the sun heat drying wasn't fast enough to keep the bacteria from growing in your milk.

Just a thought. If its the protein that binds with the clay, would gelatin dissolved in water be a good substitute for milk? You wouldn't have to worry about souring.

@AncientPottery

Жыл бұрын

That might be worth some experimentation.

You say it is the proteins in the milk that causes the seal. That makes me think it might be the casin doing the work, which would make sense because that is also used as a glue in making musical instruments and bookbinding.

The Milk Seal Diet. I like it!

@AncientPottery

2 жыл бұрын

LOL

I know it isn't traditional, and have no idea if anyone has tried it before but if it is just the protein doing the sealing then what about using unflavored gelatin? I would try making a batch of knox flavorless gelatin and while it is still hot put it in the pot, and perhaps keep it warm next to a fire, or even on the fire to keep it at a simmer while it is soaking to keep the gelatin liquid. Dump out the gelatin and let the pot cool down, then rinse off the inside and out with cold water and light scrubbing before firing it like you did for the milk.

Thanks so much for your videos. Love how professional and super informative they are! ❤️

@AncientPottery

2 жыл бұрын

Thanks so much!

Have you experimented with firing up to 600 or 660? I've seen a few tutorials mention going to those temperatures for milk glaze and they don't seem to have the issue of milk to scrub off. I'm not sure if it would still be sealed, but maybe it would lose the bad odor...

Thanks Andy, funny very interesting as usual!

@AncientPottery

2 жыл бұрын

Glad you enjoyed it

Hi Andy. My father and I have just started making pottery and your videos have been a wonderful source of information for us. We were wondering if you have ever considered sealing pottery with the oil from jojoba seeds?

@AncientPottery

Жыл бұрын

No, but I imagine jojoba oil would make a great sealant.

Why do you consistently use macro scale measuring? Switch to milliliters and you will have a much better idea of volume loss. Additionally cover or seal the lid and you will eliminate evaporative loss. This combined will give you a far more accurate indication of volume loss through the walls of the vessel.

@AncientPottery

2 жыл бұрын

Yeah, I'm just not very scientific.

If it really is protein that seals it Peas belnded with water could be a great sub for vegan. I will have to try that

@AncientPottery

Жыл бұрын

Maybe? I am no chemist, but I was told that it was some certain type of protein that was found in milk. But I have some experience cooking peas in my unsealed pottery kzread.info/dash/bejne/gZaj3MNxg8nHiqw.html

Hi Andy, if this problem of sealing pottery existed up until the last 1000 - 300 years, depending on where in the world you were, how did ancient people store things like beer/wine, where the liquid has to stay in the vessel for weeks/months? Thanks, Callum

@AncientPottery

2 жыл бұрын

They just accepted it. It's not like the liquid pours through like a sieve. There are still people in the world today who use these kinds of pots. The Tarahumara people in northern Mexico make corn beer in big clay pots.

@BonsaiBrandy

2 жыл бұрын

@@AncientPottery Thanks Andy, I had a look at the Tarahumara peoples’ corn beer; very interesting, though they appear to ferment it for only a few days, rather than some other recipes which have longer fermenting times. I have not tested holding liquid with earthenware before; does the pottery get somewhat saturated and then hold the liquid, so that the rate of loss decreases slightly over time? Thanks very much for your responses.

@Incandescentiron

4 ай бұрын

These longterm applications required better technology. The Greeks invented glass. The Chinese invented porcelain ceramics.

U can weight water before and after for better accuracy.

It sounds like what you're doing is sealing the pores in the vessel with casein (a polymer found in milk that can be turned into a crude plastic.) there might be other ways to do it by directly applying casein curds to the pores of the vessel. Of course. that's literally what all the other primitive methods do as well, use a polymer to plug the hole

@AncientPottery

2 жыл бұрын

Yes, I think that is correct and there might as you suggest be a better way to apply that material.

@olinseats4003

2 жыл бұрын

@@AncientPottery I've seen some papers that suggest that casein will dissolve in high % ethanol (50+%) solutions, though tbph, the paper I found was a bit over my head. If you could get it dissolved as opposed to being in a colloidal suspension (milk) It might be possible to deposit the casein more efficiently and thoroughly throughout the earthenware body. Ethanol will also cause casein to precipitate out of the milk in the first place. so vodka might be the answer.

Any chance you have articles or books that talk about where milk sealing took place? Or any historical data? Thanks!

@AncientPottery

2 жыл бұрын

Sorry I don't.

Thanks for your video, do you sell any of your clay so I can't make crafts with my daughter? Thanks.

@AncientPottery

2 жыл бұрын

No, I do not sell clay except slip clay. But you can use store bought clay if you want. Check out this video about how to use store bought clay kzread.info/dash/bejne/oGWu2baqnNiad6w.html

I see. Back to the oil lamp video.

Dude you are the best, can you tell me how much I need for your class?

@AncientPottery

Жыл бұрын

Depends on what class you are talking about. I have the Wednesday night Zoom class called Ancient Potters Club $20 per month or $120 per year My online masterclasses are $35 each (there are 4 and also a discounted bundle) I also have in-person workshops. All these can be found on my website at ancientpottery.how

I've got my best results with olive oil.

@AncientPottery

Жыл бұрын

Yes, it works good.

Milk sealed pottery diet. Awesome…. also keeps your hand out of the cookie jar !!

@AncientPottery

2 жыл бұрын

Definitely! Thanks.

Have you tried sealing with pine resin? I would love to see the results of that.

@AncientPottery

2 жыл бұрын

I'm sure it would work but would probably impart a terrible flavor to any food or water kept in that pot.

@ilchickentv340

2 жыл бұрын

@@AncientPottery I think I saw a video on someone making a beer or something in it. Come to think of it, resin softens in heat, so cooking would be a no go anyway. That excludes beeswax too, I guess.

Had this been bisque fired prior to soaking?

@AncientPottery

Жыл бұрын

Yes, if it had not been fired the milk would have caused the pot to disintegrate.

I thought you boil the milk inside thepot?

@AncientPottery

2 жыл бұрын

No, cooking the milk is not required, although that might be a good way to get it soaked in well and quickly.

@merrilymud7304

2 жыл бұрын

As in a reply above, there is a traditional method called Obvara. Milk and grain are "boiled" in the pot - in a raku dunking kind of way - the hot liquid quenched the pottery, sealing its 'pores' and causing it to waterproof...it gives an attractive result.

What is melk?

@AncientPottery

Жыл бұрын

kzread.info/dash/bejne/pq1qlLuzd9XfhZc.html

Why not use Butter or Ghee?

Haha

a milk sealed pottery diet plan Huh!?? funny

the protein you are talking about is casein! fun fact, in a similar process to making cheese, you can extract the casein and make cups and bowls and plates, and the best part is, if you throw it outside, it'll biodegrade in just 30 days! which is why i think it'd be a WONDERFUL alternative to Styrofoam plates, of course if you get a press to press the casein! and it'd reduce SOOOO much Styrofoam waste!