So a couple of things have conspired to get me thinking about this project again.
One of my friends who's a full scale pilot recently bought a Velocity XL which is a composite kit plane, and he's been learning how to repair and maintain it himself. He took a week long class from the manufacturer, then another class from EAA on composite construction. He liked the EAA class so much he wants to send me to it - which I'm totally up for an hope happens. But it's got me thinking about composites again and how I've wanted to experiment with some of my own ideas.
And someone on the v1engineering.com forums where I posted about this since I used my MPCNC to cut the parts recently asked me a few questions about it which brought it back to mind.
So with composites on the mind I did a bit of reading and found
@HilldaFlyer's excellent article on covering DTFB:
https://www.flitetest.com/articles/super-strong-waterproof-foam-core I also remembered his DTFB tiny-whoop:
https://www.flitetest.com/articles/foam-whoop So figured I may as well give this a bit of a try.
However, I don't have much on hand as far as FG cloth - just some small bits of heavy cloth from my friends full scale plane....and some really nasty super thick fiberglass matt strips from a friends boat project. Neither big enough or suitable for trying to cover DTFB.
But I also saw that Hilldaflyer found red rosin paper worked almost as well as FG cloth in his experiments so Figured I'd hit Home Depot.
I came up empty on rosin paper but I did get some of the bondo FG cloth. I wouldn't recommend it but it was available locally and I'm more interested in stiffness than light weight right now so figured it would be fun to experiment with. I also picked up the bondo fiberglass resin because all I have is some west systems G/Flex and some Devcon 2 hour...neither of which I had a whole lot of.
So...I got home cut an ~13" square piece of DTFB and peeled the paper off of it. Then cut out two pieces of the bondo cloth slightly larger than the piece of DTFB. Layed down some plastic wrap to protect my work surface and mixed up 1oz of the Bondo resin....poured it out and used a hotel room key to squeegee it in. 1oz seemed to be just barely enough which had me feeling pretty good about this.
Then I flipped it over and repeated on the other side. Here I started to get nervous...thought I smelled foam melting and 1oz seemed to be WAY too much resin...so scraped off all the excess then put another layer of plastic wrap over it - covered it in a flat board...put some weights on it and went out for a few hours.
It's 95f out today and this was outside....Bondo claims 2 hours for this epoxy to set at 75f. Well...2 hours later I've got a soupy mess with no foam. It appears the Bondo resin dissolved the DTFB
Oh well. Guess I should break down and order some good resin and a few yards of proper cloth....Still not sure if it will be stiff enough....but I need some FG for a few other projects anyway so may as well get some supplies I figure....more to come....