Talk Composites - The Forum for Advanced Composites

Alligatoring

http://www.talkcomposites.com/Topic3302.aspx

By shaas8 - 11/9/2012 3:54:48 AM

Okay so I just completed my first mold and everything looked perfect...from the outside. As I pulled the part from the mold I noticed the part had been completely alligatored through the OEM paint and into the abs plastic part itself.

What caused this?! I didnt use too much MEKP I actually used a little less than I was supposed to. I waxed and PVA'd several times while useing the proper precautions of waiting to dry in between coats. The only thing I didnt use that could have been a causing factor is a hi-temp wax. I actually left it at home so I used Honeycomb wax or HoneyBee wax..something like that. It comes in a yellow container.

I will be producing more molds from plastic parts and dont want this to happen again.

Thanks for the help!
By fgayford - 11/22/2012 10:16:09 PM

Well I think it isn't alligatoring of the gelcoat but styrene attacking the paint and plastic. You must not have had a good barrier with your wax and PVA.

If you want to have no risk of this happening again use epoxy for your mold. (after you wax and PVA)

Fred