Problem with Casting

Signed-In Members Don't See This Ad
Rounder

Rounder

Member
Joined
Jan 16, 2011
Messages
753
Location
Marlin, TX
I have a question for you more experienced guys on a problem I seem to be having with my casting. I am using the Casting Craft resin from Micheal's. I poured a mold last night in one of the soda bottle molds. Within an hour or two, a crack had already shown up in the casting. You could see it through the clear plastic of the mold. I have poured 5 of them in these molds so far and this cracking has occurred on 3 of them. I had a little under 2 ozs. of resin and added 8 drops of catalyst. Any ideas as to what might be causing this?
 
Signed-In Members Don't See This Ad
PTownSubbie said:
seamus7227 said:
i would say your resin got too hot! try using less catalyst
Click to expand...

+1 on this. Likely heat related crack..... I have had it happen before also...

Did you feel any excess heat when you checked it and saw the crack?
Click to expand...

Local temps last night were in the 30's. 66 During the day. I did this in a well vented room in my house and it was 71 degrees. When checking it I did not feel any excess heat. Just very slightly warm. I will try to get a picture tonight after I get home before I remove it from the mold.

Thanks for the ideas.
 
Somehow I missed that part Steve:biggrin:. I must've been exposed to way to much PR fumes!!
 
Heat from curing can definitely cause cracking. Using round molds can also compound the problem. Heat is dissipated out the exposed surface on the casting. With round molds the only exposed surface is the open end. Heat builds up faster than it dissipates so it collects in the interior of the casting. Too much heat buildup and cracking can occurr. I would reduce the MEKp and see if the casting gets better. I use 3 drops per ounce with horizontal molds. You may want to try two and see what happens. Good luck with solving your problem and happy casting.
Do a good turn daily!
Don
 
Castin Craft is also pretty inconsistent in its formulation. A big reason for buying Silmar 41, which so far has been very consistent.
 
DurocShark said:
Castin Craft is also pretty inconsistent in its formulation. A big reason for buying Silmar 41, which so far has been very consistent.
Click to expand...

I have thought about using the Silmar but just can't seem to find any 40% off coupons for it anywhere, lol.
Thanks again for all the suggestions. I will try the cutting back on the catalyst and see how that works.
 
As far as the silmar goes you are right you can't find discount coupons for it but if you calculate the cost of the casting craft per quart it is around 21 dollars. Then gas to go get it and then you have to buy the memo for it. That comes to between 75 to 95 dollars. Not including Your gas. I just ordered a gallon of silmar from illstreet and pd alittle over 50 dollars for it. Plus it comes with the mekp. So I will be buying it from illstreet more often. Just my two cents. Maybe the more experience guys will have something different to say
 
You must log in or register to reply here.
Back
Top Bottom