Wednesday, July 11, 2007

Wingnet rails, part 2

Today after work I un-molded the support rail. Here's how it turned out:

Looks okay, but it felt quite thin...

...and not quite as stiff as I was expecting. As soon as I picked it up, I said to myself "shoulda done that fifth layer of glass". The plans only called for four, but I had a fifth layer ready to go yesterday while doing the laminate. I almost put that extra layer of glass on, but at the last moment decided to keep faith in Ian and keep it "per-plan". Logically that has to be the right decision, but it's hard to resist the urge to "just beef it up a little".

Then it was on to the main support rail. First I sanded it all down, got rid of the rough edges, and smoothed over the corners including running a small round-over bit down the one right angle corner. Here it is after covering it up with masking tape:

Then it was time to prep the rest of the vacuum bag materials: two layers of peelply, release film, breather, and bag film with mastic attached. Oh yeah, plus the glass; it's fun cutting four 10' long pieces as they come off the roll:

Finally it was time to wet-out the glass. Working with 10' lengths is fun. Here I am wetting out and rolling up the first piece:

See all those little strings of glass hanging off? It's times like this that I say to myself "why didn't I decide to use the glass with a backing mat so I don't have to deal with this crap?" :) Here is the form with the second or third layer of glass rolled out onto it:

Originally I thought I would make a real bag out of two pieces of bagging film, but changed my mind because there were a lot of little sharp edges underneath the form; many were in hard-to-reach spots and I was worried that these would poke holes in the bag. So instead, I bagged the form against my workbench countertop. With such an odd shape, this has some drawbacks like, will the pressure stretch the bag too far? Well it hasn't yet but we'll see; the bagging film and mastic is getting quite the workout:

The pump took a long time bringing the pressure down, and never got higher than ~22 lbs; which means the vacuum switch is useless since I have it set at a 25lb cutoff. With the bag and the mastic stretching so much I guess I can't expect much better. Anyway, I don't care if the pump gets an overnight workout as long as the part turns out good.

No comments: