Archive of the Yahoo! Groups mailing list for the Bug hand-launch glider 2002-2018

From: "Chris Lewis" <christopherlewis@...>
Date: Wednesday, October 9, 2002 9:41 AM
Subject: Re: FG tail surfaces?
What Bob said... We've been building LN tails with waterborne polyurethane (Flecto Varathane Diamond Wood Finish in the blue can) with great success. Take your 1/16" sheet stock, drench a paper towel in poly and soak the sheet on both sides (important to avoid cupping). By the time you are done soaking take a clean paper towel and start rubbing the poly into the wood while rubbing the excess off at the same time. This forces the poly into the wood fibers and creates a composite material. When both sides are wiped down stand the sheet on one edge to dry. It should dry straight every time in only a couple of hours. If there is some cupping, press under books between some plastic wrap overnight. The water evaporates leaving only the poly molecules and adds little weight. You can then cut out your parts and sand to shape. Here's the great part. The poly changes the balsa fibers enough that they are now attracted to the bench instead of floating into the air! I then take .75 oz glass and just lay it over the finished piece. I take my thin CA or thinned wood glue and just drip it onto the surface. The glass wets out and you can wipe off any excess with a paper towel. Instant sandwich! You can even reduce glass coverage to the high stress areas and then treat the balsa edges with CA or Elmer's for a nice hard edge. You can try this for the cost of a small can of WATER BASED poly at the home enter. You'll love it. Chris --- In BugHLG@y..., "bob_chiang2" <rhc3@c...> wrote: > --- In BugHLG@y..., "Dan" <danstrider@a...> wrote: > > I'm curious about creating really light and stong tail feathers. > > > > For what it's worth, I just used relatively light 1/16" balsa treated > with water based polyurethane (per the Little Nipper model) for my > Bug. With the cruciform tail, I have only broken the vertical fin > once: when I missed a catch and the model fell straight back onto the > fin. I was skeptical of using 1/16", but it has been plenty strong > enough without reinforcement (except where it joins the fuselage > boom).