Re: REFLECTOR: Caenter spar Sweep

Ron- the fuselage halves are most likely asymmetrical. On mine the port side is about 1/2" wider from a string run nose to tail than the starboard. This has all sorts of ramifications from the angle of the canard bulkhead and centering of the canard to location of the strake baffles. You may find your engine bulkhead is also slightly angled as a result. It is difficult to check with the engine bulkhead in place but you might be able to suspend a string and use plumb bobs to establish centers on the bulkheads. Once this characteristic was identified many builders started setting their bulkheads square to a centerline. How you deal with it at this point is up to you- I wasn't aware of the situation when I did my spar but I did center the canard on the fuselage and set it parallel to the wing spar. -Bill

prototype 'Super' Chipmunk N18EF
Velocity Classic RG N6098S in the works

From: Ron Needham

To: reflector

Sent: Saturday, June 26, 1999 12:05 PM

Subject: REFLECTOR: Caenter spar Sweep

I am Installing my center spar on an XL 173 and I am having problems getting it in right.

To get the Equal Dimension at the outer bolt holes I have to shim about 1/4 of an Inch

out on the left side of the bulk head .I do have the Engine bulk head in and it is right on

the money Dimensionally from the center bolt hole, Equal dimensions on both sides.

The manual also does not say to center the spar in the fuselage I assume you just would do it

out common sense .But you know what they say about assuming.The only other way to get

the required dimension is not center the spar and then it ends up about 1./14 in off set and

that just does not seam right .

Any Help

Ron N34CV