qvevri qvevri fermentation vessels

[Pres]

Also when throwing large try out the pounding opening technique for the opening  up. This will assure a well compressed base area.

 

 

best,

Pres

[Rae Reich]

Nice work, Nancy! 

I have an extra-large bat that I can use for platters or whatever. It's Masonite, 18" across, so I have to take the splash tray off of my Brent C to use it and prop a large sponge at the edge of the bat to catch slops. 

[Pres]

Most of the time when I am throwing large, it is right on the wheel head, and it sets there until completely finished. Then I cut if off, and if needed trim when leather hard. Most of these are too large to do the bat sandwich flip!

 

best,

Pres

[NancyE]

I

Is it possible to build a kiln for these large pots that can use both gas and wood?  To work larger I need to build a kiln and I think as a beginner I could have much better temp control using gas.  I eventually would like to try wood but I know it would require a huge learning curve.  I have an endless source of wood from our property and I hate to waste it when we are clearing and buring off piles of wood while reclaiming our fields. My latest pot is 27" tall and 17" diameter at the burge. Nancy

 

[Magnolia Mud Research]

3 hours ago, NancyE said:

I

Is it possible to build a kiln for these large pots that can use both gas and wood?  To work larger I need to build a kiln and I think as a beginner I could have much better temp control using gas.  I eventually would like to try wood but I know it would require a huge learning curve.  I have an endless source of wood from our property and I hate to waste it when we are clearing and buring off piles of wood while reclaiming our fields. My latest pot is 27" tall and 17" diameter at the burge. Nancy

 

YES, you can build a kiln that can be fueled by wood and/or gas. 

My approach would be to build a kiln to fire a single large pot; you would learn the basics of fueled firing and kiln building and from that knowledge you can grow as you needs grow.  You would need to have removal burners for gas.  

Always remember a kiln is just an insulated box with a heat source.  If you can build a bonfire pit  just put walls around it, you will  then have a wood kiln; put a brick pile in the middle for the pot and you are on your way.  

download and read the pdf book: 21st Century Kilns,  by Mel Jacobson and Friends
from the paragon website: https://www.paragonweb.com/ManualInfo.cfm?CID=212 
make contact with Mel for online help if you need to.   

also look at: 

Steve Mills Backyard Kilns
https://archive.org/details/Steve_Mills_Backyard_Kilns 
 

 

LT
 

[NancyE]

Thank you LT for the excellent resources.  Everything you said is spot on for my current situation and knowledge.  N

[Mark C.]

A few thoughts

Its harder to control heating in gas and wood kilns in the early stages -which is critical with large thick pots. It can be done but you need to really work at the slow heating heating on thick wares.

If I recall you got an order for two pots-so building a kiln may cost more than the two pots?? of course the learning is priceless.

A 25 gallon pot should fit in a normal electric kiln. Which can be be controled very easily in early heating stages .Slow is the key think wil a long candle period.

[NancyE]

Thank you Mark C, of course you are right.  I can only do this order in my electric kiln and very slowly.  My kiln has Lo, Med, and High settings and I was planning to fire the pots to cone 06, my usual bisque cone.  Do you have suggestions for how long on each setting I should hold before stepping up?   As for building another kiln, it's for a future project if the fermentation vessels are a success.  The folks with the vineyard are planning to buy more, and I may be able to sell more in town.  I thought gas would be easier to control and have a more attainable learning curve than wood.  But if I'm going to invest in building a kiln, it would be best if it could be dual purpose.  I will need to sell several-many pots to afford to build a kiln.  We have been looking for brick and it's way too expensive for now.  Does anyone know if the bricks from Alibaba are appropriate for kilns?  The price difference is the only thing that makes me suspicious.  I appreciate your and everyone's thoughts and advice.  This is completely new territory for me and the grapes are ripening as we speak. Thanks, N

 

[Mark C.]

I was going thru some older ceramic monthlys today and found a photo article on throwing upside down.May do you some good.

You may have a copy to check out if not I took a few photos  and will post in the near future-it was out of the  1954  issues.. Not sure how many of these are still left out there..I was one year old when this piece was published.Its all been done before they say

 

[NancyE]

I've included pictures of my third pot and unfinished fourth pot.  Since I am trying to throw them in sections, the walls are coming out thinner (about 3/4-1/2 ", than when they were mostly coiled.  If the seams don't fail, how thick do the walls need to be to be strong enough to stand up to being filled with fluid?  Would it be wise to fire the thinner walled pots to cone 6?  I am assuming that would make it stronger to internal pressure, and since they are going to be sealed with beeswax if they are just bisque fired, the issues of the wine breathing through the terracotta walls is rendered mute.  I don't know if they plan to bury them this go around, which adds support to the walls as well as the need to limewash them from the outside to  prevent contamination from moisture from the surrounding soil.  I appreciate everyone's help and advice.  Sincerely,

N

[NancyE]

[Sorcery]

Miss! Your determination should be bottled and sold!

I am concerned with the kiln, in that I would want every element, (at least across the height of the pot) to be on at the same time. 

They should of they haven't, ahem skutt, make a program specifically for pots that need this even heating so tall.

Meh.

I'm not here to talk to you about throwing or firing.

I want you to remove your feelings about "ruining their harvest". Firstly, cause it's not going to happen, secondly, because THEY chose you, so you are merely a PART of THEIR process. Same as a kiln is part of our process, if it fails, it's our fault for not fixing or checking something. I forgot the third.  But it doesn't matter, because once you free yourself of these negative thoughts, you WILL find success.

Make 4, so you have 2 extra! 

I watched a demo where the 2 parts were made with a groove and interconnect like wooden flooring.  That may help your joins. It's the one I'd trust.

You got this! Be the tortoise!

Sorce

[NancyE]

Hello Source, I lost my first message to you so I'll do it again.  Thanks.  I had let myself be overwhelmed by my self induced pressure to accomplish this task, compounded by my fervent desire to retire from my day job.  I have absolutely enjoyed throwing myself into the project, pushing my skills beyond anything I had imagined doing, and I am pleased with the pots and my learning curve.  Thanks for the very timely reality check.  I'm trying to send a picture of my last qvevri for this harvest, not yet finished, and one just for fun when I needed to step away from the project.  Again thanks.  N

[Sorcery]

On 7/31/2020 at 1:48 AM, NancyE said:

, I lost my first message to you so I'll do it again. 

Appreciated! Another lesson in Determination!

Thank YOU!

I like the form of this one best.

I would totally plant something in that flopped one! Cut holes and Sell it!

Sorce

[Min]

@NancyE, Equipment Use and Repair section would be a better place to post your travelling kiln questions. You can just copy your post above and start a new thread in that section.

Good to hear your pots are up and fermenting wine. Cheers.

[neilestrick]

@NancyE I split it off into a new topic in the Equipment section.

[PeterH]

I was reminded of an old French tradition for making large pots:

https://deborahsilver.com/blog/tag/handmade-garden-pots/

This method of making large pots with wood armatures wrapped in rope is a centuries old technique.  The form begins with a series of wood verticals that describe the height of the piece, and the diameter of the top and the bottom. Multiple wood ribs that describe the overall shape of the pot are fixed to the central verticals.  Keep in mind that the pots are made top side down.  Heavy rope is carefully wrapped around the wood ribs.  The ribs and the rope create a template for the finished shape of the pot.  Wet clay is very heavy, and very sticky.  To throw a pot of great size takes multiple passes. Only so much of the finished height of the pot can be done before the pot needs to rest, and the clay become leather hard.  Then the next layer can be added.  A giant pot thrown on a wheel all at once would collapse under its own weight.  It is much more efficient to press the sticky clay into the rope.  The form keep the clay from succumbing to gravity.

... and yes there seems to be enough wiggle room to get the ribs out of the drying pot.

PS First saw it mentioned here in the thread rope coil pottery

[NancyE]

Thank you Peter, this is very interesting and I may have to try a version.  I wonder how rough the interior remains and how that would affect the wine.  It is so hard to work deeper than your arm is long.  I will look further into the technique, I appreciate your idea.  N

[akilspots]

i found a lot of great tips and tricks in this nic collins book on throwing large...

 

https://ceramicartsnetwork.org/shop/throwing-large/

[PeterH]

3 hours ago, NancyE said:

Thank you Peter, this is very interesting and I may have to try a version.  I wonder how rough the interior remains and how that would affect the wine.  It is so hard to work deeper than your arm is long.  I will look further into the technique, I appreciate your idea.  N

I'm not pushing the idea, just mentioning it for 'compare and contrast'.

I think that a rough interior would be unacceptable: as it breaks with tradition, and must hinder the important seasonal cleaning. I've no idea of the likely effect on the wine, but it must make any convection currents near the walls more turbulent.  Presumably smoothing/trimming the interior might be possible when the form is leather-hard, although as you say access is limited.

PS There are a pittance of qvevri references in the  How to beginning using earthen pots for wine making thread.
- One document is now accessed via https://www.qvevriproject.org/Files/2011.00.00_Elkana_Barisashvili_MakingWineInQvevri_eng.pdf
- Also see https://www.qvevriproject.org/resources

There is great emphasis on the importance of adequate cleaning, and substantial disagreement on the role of oxygen diffusion through the walls. Some regard diffusion as important (c.f. ageing port in oak barrels), on the other hand there is a long tradition of waxing the interior to hinder oxygen movement.

[NancyE]

Hello Peter,

I am in contact with the folks at the Qvevri Project, who are not potters but want to find someone to make the Qvevri, run their studio, design and build a mobile kiln and maybe a huge kiln at their studio outside of Austin, TX.  They are interested in promoting Georgian culture and wines, including the use of qvevri. 

Yes, there is really little instruction on how to make the vessels.  I have come to realize that this is partially due to the conflict between the idea of traditional qvevri production and use (I think not really realistic for US winemakers), and a modern hybrid take on the idea (see Andrew Beckham).  So my questions still are:  how do you have oxygen transfer while sealing  the vessel to keep the wine from leaking out or if they are buried, water leaching in,  just how exacting does the shape have to be to get the natural mixing inside, how thick do the walls need to be (the question of oxygen transfer again), how large does the vessel need to be to maintain the correct temperatures, what difference  does the clay you use make on the wine, what difference is made from firing the pots with gas vs wood or electric, what cone/temp to fire them, do they need to be buried to achieve the desired effect........  To top it off, I don't drink wine and cannot even begin to consider the proposed nuances of each of these variables.

I do believe that if I knew these answers, however, I could make very functional and aesthetically satisfying vessels for wine fermentation.   I'm loving the challenge and am really enjoying learning to work big.  I appreciate everyone's advice and input and am learning  with every attempt.  Where I live is very isolated, with no other potters in the area, so this forum is the highlight of my day.  So thanks for your comments and ideas, it all feeds the brain.

Most sincerely,

Nancy

[NancyE]

7 hours ago, akilspots said:

i found a lot of great tips and tricks in this nic collins book on throwing large...

 

https://ceramicartsnetwork.org/shop/throwing-large/

Thank you akilspots, I will check it out.  Nancy

[PeterH]

On 10/14/2020 at 2:06 AM, NancyE said:

I am in contact with the folks at the Qvevri Project, who are not potters but want to find someone to make the Qvevri, run their studio, design and build a mobile kiln and maybe a huge kiln at their studio outside of Austin, TX.  They are interested in promoting Georgian culture and wines, including the use of qvevri. 
...

That looks a really interesting programme to be associated with.

PS To my surprise it seems that spiral ribs on the inside of fermentation vessels are potentially useful.

Passive wine macromixing from 3D natural convection for different winery tank shapes: application to lees resuspension
https://media.proquest.com/media/hms/PFT/1/VDuHH?_s=iiT5MlyJGUtjIN33LtiG%2FoO6Ioo%3D

Jun 2021, link dead, try https://www.mechanics-industry.org/articles/meca/pdf/2020/02/mi190166.pdf

[NancyE]

Very interesting Peter, you seem to be accessing information from completely different resources.  Maybe I should step out of only looking for clay qvevri information.  Also, I suppose it can have a spiral interior without being too rough and embedded with rope bits.  Maybe even a bedsheet between the rope and clay.  Thanks, Nancy.

[PeterH]

Are you involved in the waxing process, which I believe to be usually carried out while the pot is still warm from the firing?
https://domainegeorgia.wordpress.com/kvevri/kvevri-lining/

If you are "delivering" unwaxed pots can you help by pre-heating the pot in a warm (portable?) kiln?
http://winemaking.winetrailtraveler.com/2014/08/09/preparing-our-qvevri-coating-the-interior-with-beeswax/
Winemakers that purchases qvevris that have not been waxed should heat the qvevri before waxing. They do this by building a fire in a pot and lowering into the qvevri to heat the inside. We decided that since our qvevri was small, to see if we could heat it in our oven. Making a few minor adjustments, we placed our qvevri into the oven and turned the oven on to 100ºF (38ºC). After a half hour we increased the temperature to 120ºF, then a half hour later to 140ºF and finally to 158ºF (70ºC). We left the qvevri in the oven at this temperature as we melted the beeswax.