RE: Finished modified Sig Four Star Fourty
Of course, the proof will be in the air. But so far, I'm pretty happy with the way it came out. I would say my weak spot on this was the paint job. It doesn't show up as much in the low res photos, but I definately had some blemishes. I had a couple of sags in the paint and in the clearcoat. I set the wing on some blocks before the paint had fully cured that left some marks, and some imperfectly corrected mask bleeds. On the other hand, I learned a lot too. I painted the wings first, then the fuselage. The fuselage came out better on both the masking and on the fade. I'm still no airbrush expert!
For the gears, I added ply doublers to the two ribs that support the rails forward of the spar. I cut the rails from maple. I also added ribbletts forward of the spar on both sides of the wheel well. To be honest, I don't recall exactly how I figured the forward rake and the angles of the rails. I do recall having to make small adjustments as I installed the rails. Also, a fair amount of the work was done after I had sheeted the wing. It would have been much easier if I had made the decission before hand. The same goes for running the nav lights. I had to pick up a long drill bit at harbor freight and drill through the wingtip and all the ribs one bay past the retract. Then I drilled through the other ribs from within the retract and wheel well. The holes lined up well enough that I was able to use the inner part of the original plastic pushrods to fish the wires through. The gear doors were fairly simple as the wing is constant from root to tip. I taped some ultracoat over the wing and layed up several layers of fiberglass large enough to cover the wheel wells and retracts. I then cut the gear doors and hatch covers for the retracts for a good close fit that matches the curvature of the wing.
I had heard a lot of good things about the Venture, and would have considered one if they were still available. One of the most noticable differences between it and the 4 * is the redesign of the tail. I copied the basic shape of the vertical stab and rudder from it, but did not lower the horizontal stab and elevators.
I considered buying a cowl as I believe that there is one available from one of the third party fiberglass parts suppliers. But I decided to try and make my own mold. It was mostly successful. I have a mold and could make more cowls if needed, but my plug was destroyed in the process (it wasn't polished well enough or waxed well enough and stuck in the mold. It was made from balsa blocks, so I just chunked it out of the mold.
The use of G10 was another experiment I wanted to try before committing to using it on a scale build. I really like working with the stuff. You get razor sharp trailing edges and a surface that's ready to prime without all that filling and sanding and filling and sanding and sanding and sanding then filling and sanding you have to do with a traditional glass covering. The biggest drawback is the price of the stuff, but it saves a lot of filling and sanding and sanding...
I plan on using it to cover at least the wings tail surfaces and control surfaces on my upcoming P-51 build.
Scott