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Hello everybody,

I have been asked to make 2+ 25 gal terracotta pots for wine fermentation by the end of August.  I have been researching Qvevri and other vessels, but actual detailed information has been hard to find.  I have a terracotta clay I thinks should work, and an electric kiln I believe I can fit the pots into.  I plan to fire at a cone 06, the walls will be about 1.25" thick.  I plan to build them using coils.  My main concern is, if I manage to build appropriate vessels, how can I dry them in time for firing.  If anyone has any advice or information for any of this project, I would be very grateful.  Thanks to everyone for their wisdom and willingness to share.

Sincerely,

 

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This is the kind of thing where you better make 4 of them to get two.  Get them made soon and dry on a surface thats air can get under -like expanded metal or heavy screen.

I say 4 so two can crack or flaw-now thats its an order the likelyhood is about 100% trouble is on the way.

My shop has some metal shelves from a drug store that are full of holes and stuff drys well.

Make the piece and cover and slow dry for a matter of days then slowly let dry-after a week get it as warm as you can

Not sure where you live(not listed in Name) so if its in Alaska or tip of South America then haeting would be the ticket

If you live in a humid climate than you will need some drying boost .If you live in Middle Australia then dry is easy-0 hey maybe you are in the south and its super humid ?

If you live in Upstate NY then maybe a dehumidifier would help?

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Thank you for your quick response.  I absolutely agree at least four to hope for two.  I live in north central Texas and it is pretty humid.  It seems air conditioned air dries better because it is dehumidified, maybe I could run the heater and the air conditioner as a dehumidifier.  I enjoy a challenge, but mostly if I succeed.  This is a real worry. 

Thanks,  Nancy

 

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How does the wine stay in? Does the terra cotta eventually get clogged with wine?  Is it lined with bentonite? Inquiring minds need to know.  I've heard of onggi that are water tight but allow gas exchange, but haven't heard of water tight terra cotta.

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12 hours ago, neilestrick said:

What will the dimensions be? 1.25 inches is really thick, even for a big vessel. I would think you could go half that thick and still be plenty strong.

We have calculated for it to hold 25 gal and fit into my kiln, it will be 27" tall and 22" at the bilge or widest part.  1.25" is really thick and would make it heavy.  I don't know if it is necessary for a vessel this small.  In the articles they mention some oxygen exchange through the terracotta and I don't know how the thickness of the pot would affect this.  Some modern versions appear to be fired at a higher temp and I think that would  affect any O2 exchange.

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9 hours ago, liambesaw said:

How does the wine stay in? Does the terra cotta eventually get clogged with wine?  Is it lined with bentonite? Inquiring minds need to know.  I've heard of onggi that are water tight but allow gas exchange, but haven't heard of water tight terra cotta.

They are traditionally lined with beeswax.   Sealed with a stone on the top .  The really large ones are buried in the ground.  This technology for wine making is 7-8,000 years old, originating in Georgia.  Some can hold up to 8,000+ Liters and can easily accommodate a grown man for cleaning!  Check out a potter/winemaker in Oregon named Andrew Beckham.

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Ok I checked his Amphorae -like the greek pots. All terra-cotta

High school teacher-wine maker-potter got it

Back to drying-yes on the dehumidified air for drying-slow slow-slow firing.

let us know how this turns out-a photo or two would be nice.

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19 minutes ago, Mark C. said:

Ok I checked his Amphorae -like the greek pots. All terra-cotta

High school teacher-wine maker-potter got it

Back to drying-yes on the dehumidified air for drying-slow slow-slow firing.

let us know how this turns out-a photo or two would be nice.

Yes, and of course I will send pics as soon as I master transferring pics to computer. The last thing she said to me before I left to buy clay was: "I'm so excited, your going to make my dreams come true".  Lets see how I do.  I know this will need many different trials to find the best way to make the pots.  I just hope to not be the ruin of her harvest for this year. 

N

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A few years ago I made a large bubbler fountain that was in two pieces and each half barely fit in my kiln.   I took all the rings off the kiln,  placed the pot on a shelf on the bottom and then put the kilns back together.   I did this four times because I bisque and glazed them,   I believe it took about a month to dry and it was a little over a inch thick.    I live in Kansas and it is humid and dry,  my studio is air conditioned that probably helped.      Denice

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It's not so large a vessel that it needs to be super thick. It shouldn't need to be more than 1/2-3/4" thick, and you'll have a lot easier time moving it to the kiln if it's thinner. I would build it directly on a kiln shelf, and do the unstacking method to put it in the kiln. Just remember to make it short enough to accommodate the shelf.

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(Sorry about the format, don't know what happened.)

My first attempt, for about 35 gal, flew off the wheel. My second turned out pretty good, it will hold about 5 gal. I threw it in 3 sections. I have been watching a video by David Johanson on "Throwing Large" that is really helpful and I recommend it to anyone. He reminded me that the most important steps for success are in the beginning, prepping the clay. Just like painting a house, all the serious work goes into the prep. I am adding 20 mesh grog to my clay and I think that will help with throwing and hopefully shrinking problems. I will also throw stiffer and wedged clay as per the video. My next question is, can I use coils from my pugger (2 or 3" die attached)? Rolling them out leaves me with sloppy, loose coils that are an inconsistent size. Will the spiral alignment of the clay particles directly from the pugger cause me problems? Thanks to everyone. Nancy

Edited by Min
edited by Min to fix garbled post.

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Sorry about the format, don't know what happened.  Min, thank you for fixing it.  The pedal on my wheel is either too slow or all out.  I must have dropped a tool on the pedal, it went full speed, pot, bat and a solid 20-25 lbs of clay flew across the room.  Until I figure out how to fix the pedal, I have a rag stuffed under it to keep it from taking off (not the first time), and I will only use bats that stick to the wheel via clay and suction.  I am in over my head, but I learn something significant everyday.   This forum is really important.  Thanks,

Nancy

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I looked on the internet and found how to adjust the speed control on my pedal. Makes all the difference in the world and I haven't had any pots fly off since.  Much better than stuffing a rag under the pedal!  I need to not worry so much and just make the pots from a serene place.  Pics on the way.  Thanks to everyone.

Nancy

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I have a Brent CXC.  It is working much better after I adjusted the pedal, but it still slows down when I center 25+ lbs clay.  This is all new for me, I watch a different video every morning.  I'm getting better and I hope my joints survive drying and firing.  For everyone's entertainment, I finally have some pics.  I have tried adding coils to a thrown base and adding another thrown piece to a thrown base.  When using the wheel I am limited to the size of the bat I have, so throwing the middle sections is a problem I didn't expect.  I think I could learn to like working big.

Nancy

 

resize qvevri 2 ginger style.jpg

resize qvevri 3 african beer pot.jpg

resize qvevri 4 flying pot.jpg

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No, In my old Nelson there is a picture of an upside down wheel with a pot being thrown. It was used a bit in the 70's and 80's with some artists, but I have not seen any since then.

 

best,

Pres

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Nice work Nancy!

Your control board may have an adjustment* for "...still slows down when I center 25+ lbs clay." ...am not finding any specific documentation. Some boards have adjustment for holding speed; Brent support should know (perhaps forum member(s) may know)!

*From Brent's website: "Optimal torque at all speeds -- wheel speed remains constant under varying loads for smooth feel and full control."

Edited by Hulk
err

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Throwing upside down could be a way to reach into deep pots when you have short arms.  For me, it would probably mean clay and equipment would end up flying across the studio.  After years of sanding ceilings, it makes my neck hurt just thinking about it.  Thanks Hulk.  I like the pots but I know I "cheated" by carving out the shapes as much as by throwing them.  I'm worried the sections might not hold with drying and firing.  I may try some vinegar in my joints if I have problems.  I'm not sure how such large and sometimes thick pots will turn out.  I do know I need to make more room to work and make my wheel work for me.  

Nancy

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Throwing upside down is a matter of letting the weight of the clay help with the pull. The clay is centered and usually opened up right side up then turned upside down to finish the pulls for height. 

Other alternatives are to do the pulls by 3rds pulling up 1/3 at the bottom, then going back to bottom pulling up 2/3, and then return to the bottom and pull up all the way. Myself, I force myself to get a very healthy first pull out of the bottom, and then continue each time the same way. If I have problems in any area, I start the pull below the area and pull up as evenly and smoothly as possible. Most of the centering is wet, in the end my pulls are waterless with contact point about as big around as a finger tip.

 

best,

Pres

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