ronfire Posted October 19, 2018 Report Share Posted October 19, 2018 Does your reclaimed clay tend to crack more. I seam to have more failures in the reclaimed clay. I am using plainsman m340 stoneware clay Link to comment Share on other sites More sharing options...
JohnnyK Posted October 19, 2018 Report Share Posted October 19, 2018 I have been reclaiming Laguna B-Mix, Soldate 60, and Raku clay for a couple of years and haven't had any problems with cracking. Link to comment Share on other sites More sharing options...
ronfire Posted October 19, 2018 Author Report Share Posted October 19, 2018 Would adding sodium silicate help any? Link to comment Share on other sites More sharing options...
neilestrick Posted October 19, 2018 Report Share Posted October 19, 2018 12 minutes ago, ronfire said: Would adding sodium silicate help any? NO! Do not add sodium silicate to your clay. Make sure that you're including your throwing water and slop in your recycled clay. Lots of stuff in there that needs to be in the clay body. Link to comment Share on other sites More sharing options...
dhPotter Posted October 19, 2018 Report Share Posted October 19, 2018 This is from GlazeNerd's comments on this forum awhile back... Additive for Reclaim Clay How do you determine the level of ball clay the recipe had to begin with? The Slip Test When you throw the original clay: how much slip comes up and on your hands? Coats just the inside of your palms and oozes through your fingers over time.... lower levels. Coats your palms, and oozes; have to clean a few time while throwing.... mid levels Oozes quickly and constantly cleaning off hands....... high levels. Most of the reclaimed scraps is from trimming; which has been stripped of the fines; which includes ball clay, silica, and feldspar. That would alter the properties of recycled clay: because it is the ball clay primarily that holds moisture in a clay body. The fix: blend 80% ball clay (Om4 or FHC), 10% silica, and 10% feldspar. Add 1 cup (dry) per gallon of slurry. The testing comes when you throw it after it has been reclaimed: how much slip comes up when you throw? Adjust to suit your taste. Normally within 30 days there is a marked difference, which improves over the next 90-120 days. After about 6-8 months, the process begins to reverse because the clay is actually starting to loose water: dehydration. Link to comment Share on other sites More sharing options...
Benzine Posted October 19, 2018 Report Share Posted October 19, 2018 My classes recycle as much clay as reasonably possible. I haven't had any issues with hand building projects, with it. We DO NOT use it for throwing however, so I can't comment on any issues there. Our reclaim is a mix of any dried bits, that we rehydrate for slip. When the slip gets too full, it gets tossed in a large tub, with some leatherhard/ cheesehard scraps. Those are then wedged together to get our workable clay. Link to comment Share on other sites More sharing options...
Callie Beller Diesel Posted October 20, 2018 Report Share Posted October 20, 2018 You need to keep the stuff out of your throwing bucket and your splash pan. Add it back in to the trimmings and other bits, and mix to a smooth slurry with a paint mixing bit and a corded drill. I use Plainsman too, and if you use this method, you shouldn’t have any issues with reclaim. Link to comment Share on other sites More sharing options...
tomhumf Posted October 24, 2018 Report Share Posted October 24, 2018 I was always under the impression it's best to thoroughly dry all the clay to be recycled. So it then all hydrates at the same time when you reclaim. Do some of you use all types of dryness and just mix to slurry to reclaim? I don't have a pugmill. Link to comment Share on other sites More sharing options...
Hulk Posted October 25, 2018 Report Share Posted October 25, 2018 I'm letting trimmings and chunks dry thoroughly. The wet stuff (from throwing bucket, splash pan cleanup, etc.) settles out; I'm pouring off the clear water. The dry stuff turns to sludge in a few minutes when tossed into the wet bucket. When the bucket is close to full, time to whip it up with the grout mixer, then scoop it out onto plaster slabs - seems to me this step is simpler when chunks and bits are allowed to dry thoroughly before reslaking. I'm at hobby level, not needing a pugmill just yet. Any road, reclaim seems to work well so far... Link to comment Share on other sites More sharing options...
Callie Beller Diesel Posted October 25, 2018 Report Share Posted October 25, 2018 Bone dry scrap will slake faster, for sure, but even clay fresh out of the bag will turn to mush if left in water overnight. I don't have time or space to lay out trimmings to dry out, but I will dry out bigger pieces. You do have to make sure there's no lumps left in the slurry if you're breaking down trimmings, because the teeny bits just don't wedge out. Link to comment Share on other sites More sharing options...
Cracked up pottery Posted November 23, 2018 Report Share Posted November 23, 2018 I've been having problems with my clay body just not holding together cracking is an understatement if I take reclaimed clay and twist it a quarter turn it will break apart and the best example of what it looks like is if a tree breaks in half. it just doesn't hold together. reading this I'm guessing I'm loosing something in my throwing water half the time I dump it out because I don't have more buckets to keep it. so I'm going to really try to keep my slurry. Link to comment Share on other sites More sharing options...
glazenerd Posted November 23, 2018 Report Share Posted November 23, 2018 The term used to describe that attribute in clay is " short." Actually from your description you might have blown past short. Saving your slurry is good; but you made need to add a premix back to it. A blend of 80% OM4, and ten % each of silica and feldspar makes a universal fix. Potters tend to look only at the malleability of their clay after it loses fine particles from throwing. However, those same sub micron particles that effect throwing properties- effect absorption/ vitrification of the fired piece. Those same sub micron clay particles also seal up the body, incorporating into the glassy body. As fine particles deplete- absorption begins to climb. Double edged sword. T Link to comment Share on other sites More sharing options...
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