How can i fix clay mold that keeps cracking?

[Jinx]

hi so i have been trying to make a clay mold for my fluke ahla mermaid star did. i made my first one out of a low quality clay. i cracked annd flaked as soon as it began to dry. so i thought it made it too thin i was almost poster thin at points. so i wet it down and made it thinker still cracked beyond belief. i thought keeping it moist and letting it dry slower like mermaid star did would help... nope! then i thought it coud be the crappy clay. so i used my good cone three porcelian to make a new one. still cracked. tried making it dry slowly. nope. tried using a heat gun to dry it faster, nope. so i went for super slow i spent the last 4 days on super slow motion drying. then my cats decided it was taking it too long and pulled the covering off of it last night while i slept. i came down this morning and it was open and drying. it had startd cracking badly again. but the parts aren't as small and crumbly as before. so since i spent over 30 hours of hard labor time trying to save that mold so far i decided to let it dry 100%. its continued cracking but i am going to do my best to keep it from falling apart any farther. then i am trying to find a way to save it. i think i want to permanently bond it to a piece of plywood. i can't decide if i should stick it in the kiln first or if it might breakdown more in the process. so where should i go from here?

here are the options i have thought of so far...
1. kiln it. then glue each piece together then glue it to the wood (the last 2steps are interchangable but i think it would be better to glue to the wood first as there are a lot of cracks that need to be filled).

2. glue it to the plywood first then grout it or use a caulk filler to fill the cracks or possibly a filler of some sort i a unaware of as of yet.

after either of those steps i would want to spray it with an enamel spray paint. i would use mold release when ever i would use it.


help!?!? any ideas mers???

[Mermaid Star]

Honestly when mine cracked, there was no fixing it and I just started over. I think you might be skipping a step here. What I did was sculpt the buck and then kept it wet until I was able to mold it with a mold making material. (ultracal-30) After it was molded, I removed the clay bits that were still wet from the mold by washing the mold out. If ultracal is too expensive for you there are alternatives out there. They are not the best but they are better than casting from clay. I know for a fact that mertailor uses Fiberglass resin. It is probably best to use a mold making resin rather than fiberglass but in a pinch, you could use it.

[Jinx]

thanks star!

[Mermaid Star]

Not a problem Jinx

[Jinx]

So I did the second option. I glued it to plywood then used the clay to fill best I could. Then I used the heat gun to super fast dry the clay and kept pushing mre clay into the cracks as it dried. Till eventually there weren't anymore cracks. Then like a dope I used the wrong spraypaint to cover it. So my first pull on the mold was covered with the paint. So in the future I will be finding another paint to cover the mold then wait a while before using it.

[Jinx]

5114
here is how it looks now

[Mermaid Celissa]

That looks pretty cool Jinx!

[Jinx]

Thanks abby!

[SilverSiren]

Why can't you use monster maker clay? It's oil based so it never cracks and mold making material cant stick to it. http://www.monstermakers.com/product/monster-clay-premium-grade-html Plus, it's reusable! Sure, it seems a bit pricey, but when you consider all the heartache it saves you and that it can be used again and again, seems worth it to me.

[Jinx]

Why can't you use monster maker clay? It's oil based so it never cracks and mold making material cant stick to it. http://www.monstermakers.com/product/monster-clay-premium-grade-html Plus, it's reusable! Sure, it seems a bit pricey, but when you consider all the heartache it saves you and that it can be used again and again, seems worth it to me.


I wanted to use clay I already had cause I've sunk at least $1000 into this tail already and I had the 50 lbs of amaco clay airtight around doing nothing. so that is why.

[Mermaid Crystal]

Cool fluke!