TOMMYSTA

My Feedback: (15)

Guys I have a question.
I'm making a cowl for one of my planes and I have the plug all done, the parting boards made and lined with clay and cleaned up. I started to put the layers of the Partall wax on the plug and
parting board, I've done 4 so far and want to do 10 total, should be able to finish that up tonight.
My question is after I've put on 10 layers of was can I start laying up the epoxy gelcoat and cloth or do I need to use some sort of "mold release" on top of the wax. I thought that was the purpose of the wax but maybe I'm wrong.
Thanks for all your help.
Tom

jetflyer

My Feedback: (5)

Some people just use wax, but I would recommend using PVA too. It will help insure that the part will separate from the plug when your done. The PVA is really easy to work it and only requires about 2 to 3 hours to dry so it is cheap insurance in my opinion.

Good luck and post some pictures if you can so others can enjoy.

JR Gautreaux

TOMMYSTA

My Feedback: (15)

Thanks for the quick response JR.
Can I let the PVA sit overnight or even 24 hours. The reason I ask is because only in the evenings do I have the time to complete this, unless I wait til the weekend, because of my real job. So can I apply the PVA in the evening, let it set up overnight and the following evening start with the epoxy and cloth lay up? Or does the PVA lose its strength sitting idle for 24 hrs?
Thanks again
Tom

seanreit

My Feedback: (60)

Tom, the pva can dry overnight no issues that I'm aware of. It just creates one more slippery film on top of the wax. Very common product in this process.

jetflyer

My Feedback: (5)

Tom,

Even though it only takes about 2 or 3 hours for the PVA to dry, I actually prefer to leave it overnight to make sure it is completely cured out. I will probably always consider letting it sit overnight and factor that into my building time.

JR Gautreaux

RAPPTOR

My Feedback: (41)

I USE PVA.YOU CAN SKIP THE WAX,BUT YOU CANT SKIP PVA!!!IT SHOULD DRY IN ABOUT 30 MINUTES AT 75DEG.. NEVER TOOK 3,4 HOURS..3 COATS OF PVA WILL DO FINE.. NEVER HAD A PART STICK WITH PVA..

SCHMITY

[8D]G'day Tom, If you are able to or rather have the resources, to spray the pva release on with a small spray gun which will provide a smooth clean surface for the gel coat to replicate upon. If leaving to dry overnight, which is perfectly o.k. then cover the plug after spraying the pva to avoid any dust or particles sticking to the work piece.
All the best mate.