3/4” Tailpost Question

[Shay King]

Hey guys, I’ve got the 3/4” tailpost welded into my fuselage. Only now that I’m making the vertical stabilizer do I realise that 7/8” would have been simpler.
I’ll have to add on that 7/8” piece shown on page 25.
Am I right in thinking that I’ll have to cut the top 2” of the 3/4” tailpost off and then weld on the 7/8” piece?
Picture below..
Thanks for all the help so far.

[Kamcoman77]

Great question. I'm not sure how I would try to add the 7/8" piece. From Leonard's drawings it looks like he cut the 3/4" post off level with the upper longeron and scarfed the 7/8" piece over part of it. FYI 7/8" x 0.058" tubing is a perfect fit for the 3/4" vertical stab spar. I discovered the 0.058" wall stuff earlier and just made my tailpost from 7/8" x 0.058". My vertical stab is a slip fit into my tailpost. I had some 3/4" x 0.49" 4130 on hand so that is why my upper rear longeron is not to plans spec.

[pappyadkins]

Also note, if you do the 7/8 tail post, you can use the 'upgraded' super lightweight tailwheel...

[Kamcoman77]

Pappy, that's a very good tip on the lightweight tailwheel and the 7/8" tailpost. Your modification of the original design is very nice!

[Shay King]

I’m sorry now that I didn’t pay more attention to that little note: ‘7/8” optional’.

[Kamcoman77]

You can always cut that 3/4" off and go with the 7/8"

[Shay King]

I’ve just had another rudder/tailpost thought. If you’ve installed the 7/8” tailpost, won’t that push the bottom rudder hinge out of alignment by 1/16”?

[Kamcoman77]

Not if you are using the plans built 7/8 hinges on the V Stab spar. You weld a 5/16 tube directly to the tailpost and the bolt holes line up. Here are some notes I added to one page of my plans. Pappy aligned the tailpost hinge by cutting a long 5/16"x0.058" or 0.065" tube almost in half. He was able to clamp it, aligned properly, to the tailpost for welding, then finished the cut. The ID of 0.065 needs reaming for an AN3 pin, the 0.058 is a slightly loose fit.

[Shay King]

Got it…

[Chuck in Indiana]

Also note, if you do the 7/8 tail post, you can use the 'upgraded' super lightweight tailwheel...

Just a thought about that. I used the 'upgraded' super lightweight tailwheel and was proud of myself for saving all that weight. Then.. I eventually added weight on the tail post for weight and balance. "D'oh!" 

[Brock]

Just a thought about that. I used the 'upgraded' super lightweight tailwheel and was proud of myself for saving all that weight. Then.. I eventually added weight on the tail post for weight and balance. "D'oh!" 

Exactly why I went with the tradional spring steel (Verner V3).  However, it's much easier to fix a nose heavy plane than a tail heavy plane.