Talk Composites - The Forum for Advanced Composites

Plug prep, flanging, and releasing

http://www.talkcomposites.com/Topic9281.aspx

By 20_rc51_00 - 1/19/2014 9:31:59 PM

I'm curious what people like to go with for a release agent for plugs. I personally like to go with a semi perm release agent on everything (plugs and molds) whenever possible just because it is so easy for demold if it can be used. 

In the past when I was preparing a motorcycle gas tank to be used as a plug (tank was automotive paint with 2k clear) I was able to apply the semiperm release without concern of damage to the paint/clear coat and use a caulking material between the flange/part gaps. This was also amenable to a semiperm for release. 
> I'm wondering if using a fillet wax in the flange/part gaps and using a semiperm will be possible? Perhaps I don't even need to worry about the release properties over the wax itself since it will be sacrifical and soft anyways. Would the semiperm dissolve the wax? I use frekote 770nc release.

Thanks.
By Fasta - 2/14/2014 5:33:34 AM

Wax is not like an impenetrable barrier for moulding. If the pattern coatings are not suitable or not fully cured then it will try to stick to your resin system when applied regardless of the number of wax coats.




Basically the pattern surface coating/paint needs to be a fully cured and non porous surface.

Composite shops will often use the semipermanent release systems sealer and release which is enough on it's own. You can then also wax too.

The only problem with the semipermanent release is the cost for a backyarder or one off project. The sealer system is usually pretty expensive.




If you have any experience with shellac this will also make a good pattern coating and can work with just wax on top.