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Hello All,
The plans show slots on the right upper longeron, then say that these slots should also be on the left. Is this correct? I'm assuming these slots are for the canopy, in which case only one side should be needed, and I think the slots are needed for the left, not right. For the slots on the left, do you want them to be biased towards the inboard, or outboard, which also begs the question of which is front and back. Thanks very much.

There are slots on the bottom of both upper longerons ...for the gussets.

Thanks Peter!

Just a quick follow up: how’d you deburr the inside of the square tube? I’m drilling the river holes now and try to drill them without creating too much burrs on the back side, but couldn’t think of a good way to really clean them up well.

The easiest way it to wrap some sandpaper around a wood dowel and run it inside the tube to remove the burs. You don't want to be too aggressive with this and leave large scratches inside the tube, but use just enough pressure and repetition to debur the holes. Since the rivet tails will be against this inside edge and not another sheet, once the largest of the burs are gone you've really accomplished the majority of the task. This job will only take a minute or two, and also prevents those burs from breaking off later and becoming FOD in your cockpit (you'll be amazed at what you find during your first trips upside down).

Jeff

SP1 wrote:Just a quick follow up: how’d you deburr the inside of the square tube? I’m drilling the river holes now and try to drill them without creating too much burrs on the back side, but couldn’t think of a good way to really clean them up well.

Sam,

A simple tool that's worked well for me is the 1/8" In/Out debur like this one from Yardstore: https://www.yardstore.com/drilling-and- ... r-tool-1-8

Sometimes they have them surplus for $25, which is what I bought, but they are normally $40 new. I've used it extensively whenever it's hard to get to the back of the hole. After using it exensively, I'd gladly pay $40 for the time and frustration it's saved me. I don't use it for my .025" sheet holes, as it creates a subtle chamfer (<.010" deep) on both sides of the hole and that is more than I want on the thin sheets.

I've also been using a 1/8" left-spiral hand (not chucking) reamer in my cordless drill to updrill all my #41 holes. These hand reamers are the same size as a normal drill, turn in the same direction, and have a gradual taper at the tip to ease the hole diameter from #41 to 1/8". They rarely create a burr. I only needed one reamer per wing before I noticed they were getting dull. Machine Shop Discount Tools is where I ordered mine: https://www.msdiscounttool.com/catalog/ ... _id=101875

Paul

Thanks Thomas, those are pretty interesting tools I didn't event know existed. I'll definitely check them out.