Retxy Posted March 6 Author Report Share Posted March 6 On 3/4/2024 at 11:23 AM, neilestrick said: I'm afraid I kind of agree with BlueBird. If it has half dollar size holes in it due to corrosion, the rest of it is probably not structurally sound. The non-pugmill option is to simply not wedge and not recycle. Most clay bodies are good to go for throwing right out of the bag. I switched to slab building about a year ago after 30 years of throwing, due to bad arthritis in my hands. Gotta say I don't really miss throwing. I'm happy to still be working with clay, and the challenges and possibilities of working with new techniques have me more excited about ceramics than I have been in a long time. Yes i can only hand build but for once or twice a year with a wheel ive used 20x since college 20 years ago. But since i have to mix my own clay and my dumb hands dont work, my clay is bloating super bad wven with extended blunging. Ive concluded its a mixing fault, and lack the power to mix/wedge properly. Hence the Rusty Pug. I cant wait to see what happens. Quote Link to comment Share on other sites More sharing options...
Babs Posted March 6 Report Share Posted March 6 12 minutes ago, Retxy said: Yes i can only hand build but for once or twice a year with a wheel ive used 20x since college 20 years ago. But since i have to mix my own clay and my dumb hands dont work, my clay is bloating super bad wven with extended blunging. Ive concluded its a mixing fault, and lack the power to mix/wedge properly. Hence the Rusty Pug. I cant wait to see what happens. Bloating? Usually a sign of being overfired. Quote Link to comment Share on other sites More sharing options...
Kelly in AK Posted March 6 Report Share Posted March 6 Nah, not necessarily a mixing fault. I can only guess your clay has a lot of iron in it. It’s bloating because it’s becoming vitreous at the same time something is decomposing in it, that’s usually iron around cone 6. But, I’ve had white clay bloat when I fired it too high too. One thing’s for sure, if you get that pug mill in shape there’ll be less wedging, and that’s something to look forward to. Quote Link to comment Share on other sites More sharing options...
neilestrick Posted March 6 Report Share Posted March 6 @Retxy are you digging your own clay or are you buying raw materials (or both)? Quote Link to comment Share on other sites More sharing options...
Min Posted March 6 Report Share Posted March 6 Bloating for sure is caused by overfiring but then there is also blebbing. I think that in the last 20 years or so the term bloating is used to cover both bloats and blebs but with pyroplastic claybodies, such as many of the smooth white bodies, an air bubble within the clay wall will expand during glaze firing when the glaze has melted enough to seal the surface of the clay and the air pocket expands causing a bump on the surface of the clay. These don't show up during the bisque but do show up during the glaze fire, does't have to be overfired to happen. Babs and Kelly in AK 2 Quote Link to comment Share on other sites More sharing options...
Retxy Posted March 28 Author Report Share Posted March 28 Srry i hadmissedso many lovely replies, been sick as a dog and kind of on the mend. @Kelly in AK @Min i too thoight it was being overfired. This is a vitreous clay but even when i fore it a cone below maturity its bloating. My conclusion is my piss poor ability to wedge is leaving suoer concentrated pockets of frit in areas of the clay that are then causing the blaoting when fired due to the off gassing/inconsistencies to surrounding body... or at least thats what ive been able to glean frm the interwebs. If the better wedge/mix doesnt fix then more testing until fault is fixed will be pursued, if and when i can move again. Silly body. @neilestrick buying bags of clay, too science bound to touch anything without a reliable analysis at this stage. Also cant dig due to health so bags are serving all my needs... you know except the one where my stoneware recipe doesnt bloat hahaha. On a separate note, has anyone else had difficulty getting responses from bluebird? I asked them about warranty information on the machine as i have the original documents amd they were mum. Pug updates: before becoming ill i began my little restoration efforts. I was pleasantly surprised that the rust is coming up eith reltive ease over the majority of the machine. There is a cam associated with deairing chamber that is worn all the way through and if bluebird does not respond to replacement oarts request, i guess im going to have to get that heifer welded somewhere because im not sure the part for the 440 listed on their site will fit. In other news i have sourced a material which i believe will seal the metal and prevemt future corrosion. Its called Rust Grip. Its an expensive venture but all research indicates this will remediate and prevent this problem in the future. Or perhaps its wishful thinking. And it beats the 11k i woukd have to spend for a new machine. Will post update pics asap Quote Link to comment Share on other sites More sharing options...
Retxy Posted June 1 Author Report Share Posted June 1 On 3/6/2024 at 12:12 PM, Min said: Bloating for sure is caused by overfiring but then there is also blebbing. I think that in the last 20 years or so the term bloating is used to cover both bloats and blebs but with pyroplastic claybodies, such as many of the smooth white bodies, an air bubble within the clay wall will expand during glaze firing when the glaze has melted enough to seal the surface of the clay and the air pocket expands causing a bump on the surface of the clay. These don't show up during the bisque but do show up during the glaze fire, does't have to be overfired to happen. Could this explain why my test tiles always look so rad but my pieces are bloated messes? Hmmmmmm... would making glaze a little slowr to melt oerhaps by increasing silica or clay be useful? Im getting crazing but hard to tell if bcause of clay blebs/blisters. Quote Link to comment Share on other sites More sharing options...
Retxy Posted June 1 Author Report Share Posted June 1 I had this long lovely reply and it faded into the ether. Oh well. Tldr version: Been sick, many many project delays. Machine (finally) fixed. Used RustGrip and fiberglass. Check out this video to see why this worked. Huge thanks to Arin at Volta Coatings. He answered 700 questions(literally):: highly recommend. Some pics attached, more to follow. Cam is worn thru as you can see in pics and am awaiting replacement to arrive. Could the split cam be the reason clay is jettisoned up from barrel into the vacuum chamber? Or is it that i left a gap too wide in that chamber, which i had to patch because of rust wear? Does anyone with a 440 know how big that gap needs to be bcause bluebird rep is not helpful at all. Thanks so much, all your help and comments are greatly appreciated and helped so much. Quote Link to comment Share on other sites More sharing options...
Retxy Posted June 1 Author Report Share Posted June 1 Top barrel Quote Link to comment Share on other sites More sharing options...
Retxy Posted June 1 Author Report Share Posted June 1 Quote Link to comment Share on other sites More sharing options...
Retxy Posted June 1 Author Report Share Posted June 1 Forgot to mention thin coat of jb weld fiberglass resin on internal surfaces. This was not strictly necessary but recommended for constant submersion in water... not exactly our situation but not exactly not either... so i did it. Much love and peace to you all!! Quote Link to comment Share on other sites More sharing options...
Retxy Posted June 1 Author Report Share Posted June 1 (edited) On 2/27/2024 at 10:28 AM, neilestrick said: @Retxy How much of what we're seeing is rusted metal vs old clay? If it's all metal, then the metal is in really bad condition and I wouldn't touch it. If we're looking at a bunch of clay on the surface and the metal underneath is still decent then I think sandblasting is probably the best way to go. Do not put any sort of coatings on the auger or in the hopper. They won't survive. Just leave the interior raw. Paint the exterior if you want to. About 10# of dry rust petrified clay were adhered to that barrel after the newer stuff was removed. It was a bear. Edited June 1 by Retxy Additional info Quote Link to comment Share on other sites More sharing options...
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