H Palmer

Trouble with using glue on the inside of the mould is that it will make the plaster un absorbable .... I'll try a thin layer of plaster i think. .. glue on the underside is probably fine..

HI there... i just dried out a large mould in my oven, I think it was hotter than I thought, or the mould too close to bottom of oven as it was only on 50..Anyway, end result is that there are a few cracks in the bottom of the mould... they are on the underside of the mould as well. I have looked up how to mend plaster moulds; nothing for mending cracks so what do you all think? 'Mending a broken mould' advice suggests soaking the mould in a bucket of water until completely saturated, then using a plaster mix as paint to stick the broken pieces together. i am unsure what would be the best way forward... soak the bottom of the mould a bit and add a thin layer of plaster perhaps... 'mending cracks in plaster on a wall' advice suggests opening up the cracks then adding filler to the cracks... to me that sounds like good advice, I might open up the cracks, wet the plaster and then fill the cracks with plaster mixture... Its worth a try before throwing it away I think...

I think that I have usually made my slip casting moulds with plaster of paris which seems to work well. Last week i made a load with Potters Plaster, it seems quite different so i just want to check in with you all about wether it is that different, or maybe I got a bad bag.. I used the same method that I always have; I put water in the bucket and added plaster until there was a little mound showing above the water, and then i added about a cup more. Then I left it alone for 5 mins... then i started to stir it and put in a hand to mix it.. it stayed cold but thickened somewhat so I poured it into the moulds. I tapped the moulds up and down to get the bubbles to the surface. After a while it got hot, eventually hardening. when i de-molded , the surface of the plaster seems quite rough and there are loads of tiny holes from bubbles. I never had this result with paster of paris and it seemed to heat much more quickly so does anyone out there recognise what I am saying and can advise... many thanks.. henrietta