ORIGINAL: billberry189
Hellooooo Duane, Mine came in last evening complements of Jeff's speedy response(ordered it on Friday) and UPS. The 120 AX came in the day before yesterday. Went to Graves R/C Hobby here in Orlando this morning and picked up a Dave Brown Glass filled motor mount part # 120F-1204, a set of Du-Bro 3'' super lite wheels # 300SL, a Mac's muffler # 6990, and a 16 oz. Du-Bro fuel tank # 416. Came home and got started with the firewall mounting the motor mount and landing gear mount. After looking at the photos for awhile, it dawned on me that if I rotated the mount about 30 degrees I could mount the muffler without an extension. It also brings the muffler closer to the nose of the fuselage giving it a cleaner appearance IMHO.
I can see we may be "all over the place" in this build thread. I was going to start with the stab, but you started with the firewall. I guess the best thing to do is to start with the stab, and as other things come up, comment on them at the time. You are right to do all the drilling in the firewall in advance of installation, (though Kevin didn't). I felt it made things easier. I see your Dave Brown mount, (same as I have), seems to stick out of the side, so you're going to have to be creative about what to do. Do you "lop" the extra off, groove the fuselage side, or a combination of both? Just me, but I think I'd grind the extra off even with the fuselage side. There isn't a lot of room in there, (and the final kit is actually a bit more narrow than the prototype). You are putting a larger motor mount into a narrower area. This is an area where the builder is going to have to anticipate what to do before hand.
BTW...I also used triangular balsa braces between the fuselage and firewall as much as possible without interfering with pushrods or mounting bolts. I put the triangular stock on both sides where I could for added strength.
What you have done with that "rotation thing", is a perfect example of thinking out of the conventional box, (which I'm sure we'll get a lot of). It didn't occur to me to rotate the engine 30 degrees, (I'm not great at thinking out of the box, and it turned out Kevin's engine didn't require an extension), so it looks like we have our first improvement suggestion. The need for an extension (for the OS .90 engine), was discovered way down the line for for me..one day I just said to myself
...shazamm, [X(] I need an extension on this.
Good going...