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Hey Ya'll...

I just put the upper crosstie on the front of my forward fuselage. Pre-drilling, it was exactly 32" wide at the outside of the longeron, per plans. After drilling, it seems to have shifted a hair, and now the width is about 1/16" wider. This isn't much, but since this part helps set the square of the fuselage, I'm nervous.

Does anybody know if 1/16" on this part is going to cause a problem? I test fit the lower firewall, and it fits well, but if you look closely you can see it's very tight against the hinges at the bottom, but there is a very small (I'm guessing 1/32" ;) ) gap between the firewall edge and the hinge at the top on each side.

Thoughts or suggestions? I don't really want to buy a new crosstie of a 1/16" error, but I don't want this to cause troubles later fitting the engine mount or something.

I made this part three times. I could not make the 31 3/4 dimension that they give you in the plans fit, so i started trimming it down and ended up taking too much off leaving me less than comfortable about the material left around the outermost bolt hole. I remade the part and just flat out screwed it up. Third time worked like a charm for me. I dont think that you or anyone else will ever notice 1/16" off from square, but (as i know from first hand experience) less than $10 material from Aircraft Spruce (+ shipping) can buy you piece of mind.

To be honest though, i can think of several airplanes i have seen with wings/fuselages attached an inch or more from where they should have been and they fly fine. It's all a matter of what you are comfortable with and how much of a showplane you want to make.

Hi Andy,

The only possible issue I can see down the road will be the engine mount fitting. Most people need some shims to fit the mount but you may need to add a thicker shim. I doubt an additional 1/32" on each side will matter though, so it really all comes own to how you feel about it. If you're trying to build your plane perfectly then buy or make a new part, but if you just want to fly and have a small error no one will ever notice, then just keep building :D

Thanks guys, I'll mull it over and check the dimensions again.

I'm going to leave it for now and go for it, wish me luck!