On 12 Aug 2004 02:55:43 -0700, (Lou Parker) wrote:

I'm at the point where I need to build a gas tank or 2. The sport
plane builder book shows a great way to do a custom tank but materials
it calls for are not listed (or I'm reading it wrong) so, any
recommondations on a foam core that will stand up to gas? Any
recommondations for a fiberglass system? I'm all ears, or in this case
eyes.

The G-III uses Vinyl Ester Resin and foam cores for the header tank.
I don't remember as they actually tell you the chemical composition of
the foam. It is a light tan color.

The cut the sides, bottom and back from 5# 1/2 inch foam, seal the
foam with a thin micro sphere (Q-cell) mix, then give it two layers of
fiberglass and resin on each side. These lay-ups are a bit on the
resin rich side.

You don't even get Styrofoam near Vinyl Ester resin. It dissolves it.
Vinyl Ester Resin contains liquid Styrene. Let it set around too long
and it gets "chunky".

The only drawback I can see to the Vinyl Ester Resin is the short
shelf life. Supposedly only a couple of months after being promoted,
but I get 6 months to a year after promotion. I'm just finishing a
gallon that was promoted in March and it shows no sign of getting
chunky. Only a couple more lay-ups and that can will be empty. I'm
promoting a new gallon so it'll be ready to use by tomorrow night.
Contrary to the instructions in the manual. I just pour in the proper
amount, and shake the can in all axis for about 5 minutes. Let set
over night, shake again, and then run a test batch about 6 hours
later.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

Lou