Fuselage doublers

The doublers are made from 1/8" lite ply. The rear one reinforces the stab anti rotation pin. The 3 front ones reinforce the gear block, forward adjuster, wing tube, and rear ajsuster. I like to cut lightening holes in these, as it does save a few unnecessary grams. Pay CLOSE attention to the locations of the holes if you do this step. Use the pics here as an outline. You can get a little more aggressive on the electric version. if you're using a 4 stroke, leave the wood in place.

Also note that the only 2 doublers that go all the way from top to bottom stringer are the wing tube doubler and the rear adjuster doubler. The front gear/adjuster doubler runs from the top stringer to 1/4" above the bottom stringer. Use a scrap piece of 1/4" AC ply to make sure this is a snug fit. if it's loose you'll have to slop some epoxy in there and the joint will be both weaker and heavier. So take your time and make it fit.

After you install the doublers, tack glue the sides together back to back. Now with a long sanding block, true up the sides so they match perfectly and especially make sure the top side is absolutely straight. This is critical for alignment purposes. Also take care not to sand too much off, we're talking 1/64" tops.

Don't break them apart yet, we have one more thing to do first.....