What coating to harden blue foam? - RC Groups
Thread Tools
Oct 21, 2003, 06:27 AM
Registered User

What coating to harden blue foam?

My flying buddies and I have discovered the joy of plane building from blue foam. However, the foam as you know is quite soft and easily marred from handling. What is the best light weight coating to apply to give these planes a tougher skin? My one friend brushes 20 minute epoxy on his; it makes them harder, but he certainly pays the weight penalty! There must be a lighter weight solution out there...what are your favorites?
Sign up now
to remove ads between posts
Oct 21, 2003, 07:02 AM
Crash Master
Gene Bond's Avatar
I 'Temper' the surface with a heat gun. Just slowly and evenly wave the heat over the surface, until you see it start to get shiney. I really strengthens it, and helps reduce 'rash'.

Warning: once tempered, tape doesn't like to stick as well, so you can iron it, or lightly sand under the tape.
Oct 21, 2003, 07:05 AM
Registered User
rtherbe's Avatar
Starting with the easiest and probably lightest would be clear or colored packing tape you first have to prepare foam by spraying a light coat of 3m777 contact adhesive that will help it last longer and can be used in cojunction with straping tape to strengthen wing panels, top and bottom, give it a try the stiffining improvement is incredible.

Then the method I prefer to strenghthen foam is waterbased polyurethane (satin) and lightweight fiberglass cloth I think 1/4 oz. cloth is what I use, very thin and light anyway this method is usually used for a formed scale like plane. I use a small touch up paint roller to apply a light coat to sanded foam then lay the cut cloth on panel roll out smooth let dry to a "tacky" then roll on a decent coat(most of this will be sanded off) some people mix talc with final coats to fill weave but not always necasary with the very light cloth. Now you'll have a perfect base for a light coat of acrylic water base color. just sand in decending paper weight ig. 150-220-400 till you have the base textureyou like before painting.

There are so many methods out there some even use Solite which I'll try myself some day just browse R/C Groups the best forum anywhere for our hobby and you'll find ideas and techniques galore....
Oct 21, 2003, 07:08 AM
Registered User
rtherbe's Avatar
Good idea Gene I'll try that one on my ultimate bipe I am building at the moment thanks

Quick Reply

Thread Tools