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

From: Allan Wright <aew@...>
Date: Thursday, January 16, 2003 1:57 PM
Subject: Re: [BugHLG] Tail Group Question
> I have been wanting to build a Bug for a while and have a quick question. I have the designs for the cruciform tail group ready to go and was wondering what might be used to "toughen" up the balsa. It says to use 1/16", but it seems like it needs something to stiffen and harder up the wood for a slightly more robust tail group. I was thinking of thinning out some white glue and painting it on then giving it a light sanding, is this necessary? I haven't made the (+) tail on any of my bugs, but here's a technique that I've used to toughen up 1/16 sheet flying surfaces. cut 2 pieces of 2-ounce fiberglass cloth, a little bigger than the surface to be strengthened. Spray lightly one side of each piece of cloth with 3-M Super 77 spray adhesive. Apply the cloth to the surface making sure that it's nice and smooth and the part is not in tension (warped) at all. Mix some 30-minute finishing epoxy (I use Z-poxy, but Wes systems, etc. is fine.) Squeegee some epoxy onto the cloth, then squeegee as much as you can out of the cloth. Place a sheet of wax paper onto a flat surface, then the piece of glassed balsa, then another piece of wax paper, then a piece of 1/4" plywood. The good aircraft kind with no grain to the surface. Then weight down with a good weight, like several cinder blocks - you want 20 lbs. or so. Let cure a couple hours. When you're done you'll need to trim the excess cloth from the part and sand the edges round/square/tapered as necessary. Always do both sides of any part at once or you'll end up with a potato chip. Also be sure to let the part fully cure - I go 4 times the cure time rated on the epoxy, overnight if possible. If you want a lighter surface with less added strength, you can use .75 oz. cloth, but at that point you're not much stronger than a good application of monokote. Al =============================================================================== Allan Wright Jr. | Without love life's just a long fight - Southside University of New Hampshire +-------------------------------------------------- Research Computing Center | WWI Modeling mailing list: wwi@... Internet: aew@... | WWI Modeling WWW Page: http://www.wwi-models.org ===============================================================================