tggilkey
Posts: 127
Joined: 11/26/2003
From: Mendota Hts.,
MN, USA
Status: offline
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Hi Jon --
As far as you and I are concerned it is! I'm building one also -- a second one. Is there a specific alignment question you have? I know some have said the holes worked and others that used them more as “suggestions.” I tended (with the first one) to use them as suggestions -- actually for the wing, only used the main spar tube holes. For the stab, I used both spar and anti-rotation pin holes -- but with adjustments as necessary. Prior to this decide whether you are going with incidence adjusters or the stock setup -- open the holes for what you will need. For the main spars for wing and stab make one side's holes a good fit for the socket material and don't mess with it -- the other side will be the floater for trammeling adjustments. Basically a good setup (which I gleaned from others in this thread) was this:
On a flat table (important), have the front bottom of the fuselage (no engine, no engine cowl) resting (just touching) the table. Yeah, the fuselage is round so it will have to be stabilized -- I used a fixture which had a base with 2 threaded uprights; a cross piece between the uprights whose height is adjustable by means of washers and wing nuts. The height is adjustable and because each side is adjustable independently the vertical fin angle relative to the table top can be adjusted also. Prop the tail up from the table 45mm; then adjust the fixture holding the nose such that the fuselage bottom (right at the joint where the engine cowl would be) just touches the table.
Mark the location of the support fixture cross piece on both the fuselage (both sides) and on the cross piece (for repeatability...); also make your support block just slightly wider than fuselage width at the tail -- you may need the real estate for setting/measuring incidences later on. I tacked the block to the bottom of the tail after bumping the setup off the block twice... and having to start over with the setup. Hence the marks and tack job...
Get the fuselage setup so the tail is propped up 45mm, the front of the fuselage minus engine cowl just touching the table and the fin vertical to the table.
Now you are ready to set the alignment of the wing relative to the fuselage. Assemble the wing panels on the tube (and fuselage) and adjust the other side (the “floater”) until aligned as viewed from the back and from the top. Make the wing tips equidistant from a point on the bottom of the fuselage (just in front of that 45mm block). Come up with something repeatable – I used a small (1/4” wide) metal tape measure – sacrificed it years ago for this purpose – drilled a pivot hole on the center of one end and held it to the center of the fuselage at the back with a #2 sheet metal screw. Either the hole gets covered by the tail wheel or filled when done. The tape doesn’t stretch like string and with consistent pressure applied doesn’t sag much. There are better methods but I haven’t taken the time to put them together. Check out Bob Noll’s Perfect Alignment series.
When doing this stage of the alignment keep the surfaces close to zero so your other measurements don’t get skewed. Judicious use of tape can help hold incidence on one side. Sometimes the tube and socket fit is enough. I set the initial incidences at 0 by measuring LE and TE the same distance out from the fuselage or in some cases by a line established on the fuselage (drawn on removable tape of course…). I think I used 1 turn of positive incidence on the Gator adjusters (with the adjusters at 6” centers from the tube). After adjusting the screws, check the TEdges for agreement and same for Ledges. Obviously the differences should be the same. I was quite pleased with the way the first one trimmed out.
Digest this and many of the postings in this now longer thread… Look for things from PeterP, MalcolmH, David Gibbs and some others like Eric Henderson. I borrowed liberally from them during my build. Their advice was sound.
Good luck with your build and feel free to either post more questions or PMail me.
Tom
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RE: Impact - 
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