.dsaavedra. Posted October 5, 2008 Report Share Posted October 5, 2008 after i make a mold with plaster of paris, do i have to bake it or anything or can i just let it dry for 24+ hrs to get it fully hardened? Quote Link to comment Share on other sites More sharing options...
uwfishmd Posted October 5, 2008 Report Share Posted October 5, 2008 after i make a mold with plaster of paris, do i have to bake it or anything or can i just let it dry for 24+ hrs to get it fully hardened? I just let mine dry for 24 hours. I think that after you let it dry then you need to apply a sealer not sure what kind though. Quote Link to comment Share on other sites More sharing options...
uwfishmd Posted October 5, 2008 Report Share Posted October 5, 2008 After you let it dry for 24 hours you need to seal it with this: Any kind of epoxy or mod podge will work. Don't get carried away just a light coat will do. Then your mold should be finished. Quote Link to comment Share on other sites More sharing options...
nova Posted October 5, 2008 Report Share Posted October 5, 2008 I usually bake mine in the oven set at 150 for a couple hours. Then I take it out and set it on newspapers to absorb any moisture left as it cools. Just don't set your temp too high as this may cause the moisture to turn too steam and crack the mold. www.novalures.com Quote Link to comment Share on other sites More sharing options...
.dsaavedra. Posted October 6, 2008 Author Report Share Posted October 6, 2008 ok thanks guys. once it hardened i planned to seal it with a few light coats of elmers/water 50/50. from what i've read this seems to be a very good sealant. i just wasnt sure how to harden it. Quote Link to comment Share on other sites More sharing options...
bojon Posted October 6, 2008 Report Share Posted October 6, 2008 One time I made a POP mold to cast a lead head I wanted to make.The mold came out excellent,but I set the oven heat too high,and it shattered.The lower temp suggested here would work.My second mold I allowed to air dry for a couple of days,and it worked. Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted October 6, 2008 Report Share Posted October 6, 2008 I weigh my mold before going into the oven. I then aim for a 30% weight loss in the drying process. I remove the mold at intervals to weigh and monitor progress. Over cooking will make the mold brittle and powdery, rendering the mold useless. Would be a shame to ruin the mold at this stage, so I believe the extra work is well worth it. I can see a few heads shaking, but I cannot help myself, it is the engineer in me. After a few molds, you get a feel for how long to cook the mold anyway. Dave Quote Link to comment Share on other sites More sharing options...
GB GONE Posted October 6, 2008 Report Share Posted October 6, 2008 My favorite way to cure my molds (if you have the time) is to put them on a towel in your car. The temp gets to be warm enough and the towel will wick away the extra moisture at the same time. Saves electricity or gas and cures the molds at a good pace. Some are riding shotgun right now!!!!! Jim Quote Link to comment Share on other sites More sharing options...
longhorn Posted October 7, 2008 Report Share Posted October 7, 2008 I bake my molds at 325 for an hour per inch thickness. Quote Link to comment Share on other sites More sharing options...
Hookfin Posted October 7, 2008 Report Share Posted October 7, 2008 I quit baking mine..I do swab it down right after removing the pattern with a brush full of elmers. Then I let is dry slowly in a cool dry area. It makes the elmers shine and cures up better..I have had no problems since doing this....works for me. Quote Link to comment Share on other sites More sharing options...
HJS Posted October 9, 2008 Report Share Posted October 9, 2008 Hey ghostbaits - I use the same technique of drying PoP on the dashboard of a car. But now that winter is approaching I'll switch to setting them under the wood stove amongst the cats. Quote Link to comment Share on other sites More sharing options...
