Simple Plug-What to use as a release Agent
 

I have read most of the posts in this forum but am doing my first fiberglass project and wanted to throw a couple of questions at you. I am making a simple plug. Basically it is a square box (5"X5"X2.5") box made with a plywood base and balsa sides. I am planning to paint the box with a primer base then a coat or two of paint. Then I want to use several coats of car wax (without silicone), then build my fiberglass layers over this base. I figured the paint would help smooth out the box.

Will this work? I would like to use the car wax due to availability and cost. I can’t find PVA or any of the waxes made specially made for releasing. I am going to be making only one or two of these boxes for now and don't really want to put out a lot of money for this project. Since it is a plug and not a mould, I shouldn't have to worry about fisheye problems since I will be painting the outside.

What kind of paint should I use when the form is finished? I am probably going to bang the box around a little bit and would like a paint that is durable.

Thanks for your help. I am kinda excited about working in this medium

RE: Simple Plug-What to use as a release Agent
 

I've used automotive 100% Caranuba Wax, but it takes multiple coats of it, 6-10 in my case. I'm still a novice at this, so your mileage may vary. I purchased Evercoat liquid PVA from my local marine supply store (West Marine). They also sell West Epoxy resin and mold release wax too. You might want to look up a marine supply/repair in you area.

Here is a link to my thread, pages 1 and 2 show the products I used. http://www.rcuniverse.com/forum/m_6794670/tm.htm

Hope that helps.

-Jorden

RE: Simple Plug-What to use as a release Agent
 

if you don't taper the box you'll play hell getting it to release regardless of what you put on it.

RE: Simple Plug-What to use as a release Agent
 

When I wanted to make a one-off cowl mold a few months ago, I was in the same situation. After a little research, I discovered that Johnsons Paste Wax is almost (if not all) 100 percent carnuba wax. My plug was constructed from the green florist foam, but the surface was pretty unstable, so I coated it with finishing resin. I still wasn't happy with the plug surface, so I covered it with aerocote lite, and then applied 7-8 coats of Johnsons paste wax. Although it was a little sticky getting the mold off the plug, it worked adequately. I then used the Johnsons to wax the mold, and again it worked adequately. I haven't tried to pull a second cowl yet, but I'm guessing it will be a little easier the second time around. For release, I went to a local craft store and found a spray mold release (I think it was in the ceramics section). It doesn't say what it is, but it looks like its probably PVA. A 4 oz bottle cost a few bucks, but it worked along with the Johnsons paste wax.

Brad

RE: Simple Plug-What to use as a release Agent
 

You could cover your plug with Monokote or similar heat shrink film, and possibly get away without much release media.
I have also heard of people using hairspray for release, it is pretty much like PVA.

Lars

RE: Simple Plug-What to use as a release Agent
 

Kiwi natural shoe polish works pretty good as a release agent in a pinch.