ok, so here is what i did for the gear door attachment points. i couldn't duplicate BT's plan method of using lithoplate as i didn't have enough gap to play with. so, even though not really scale, i made my own mounting flanges using polyester resin and balloons. to do this first i marked and area roughly 3/16" wide on the oleo using a very homemade marking jig. then i applied masking tape to a thickness of slightly more than 1/32" to outline the marks and then cut out a portion of the tape down to the last piece so as not to interfere with the door. i also put several coats of mold release on the doors to prevent the resin from sticking to it. then putting the oleos back in the wing i mixed up some resin and balloons and put a bit on the oleo then put the gear door on top, taped it down and turned the wing over right-side up so the mix would settle toward the door.
pic 3-4: once dry i removed the door and cut back the mix to approxiamately the marked area. the mix wouldn't go all around the oleo so had to mix up some balloons and add it to the backside.
pic 5: then with all dry i sanded down to the tape and then removed it. then i drilled two holes to accept #0 x 3/16 screws. as you can see i really didn't have much room to work with. with all that done i soaked the flange in ca to harden it up and attach it firmly to the oleo.
pic 6-10: the result worked very well. it's sturdy and the door fits perfectly to the wing. one thing here. i'm assuming the prototype door fit flush up inside the wing; however, i didn't have enough room to play with for that so i'll just let mine rest on the wing bottom.
< Message edited by tubig -- 6/10/2006 12:41:35 PM >
while waiting for the primer on the wing to dry i started work (again) on the tailwheel. thought i would go ahead and finish this up. since i already had a washer soldered on to one side, i soldered on a washer to the opposite side. this washer is cut out from .008" tin. this, then, becomes the outer brass axle/wheel assembly.
pic 2-3: then after soldering on the inner brass tubing i tinned it and soldered on the outer brass axle/wheel assembly. then cut off the extra brass tubing and filed it down. so at this point the tailwheel is permanently mounted to the fuselage.
pic 4: now i wanted to make a reasonable facsmile of the prototype's tailwheel bracket so to do this i needed a skeleton to hang some polyester filler on. so i soldered on a piece of wire to mirror the tailwheel wire.
pic 5: then in order to have a smooth inner part to the bracket without having to sand in such a confined place i made a base from plastic that i heated to conform to the shape of the wires. being plastic, the polyester filler won't stick to it and will pop right off. i also added a balsa oleo which i'll cover later with something to simulate the leather boot.
6-8: so then just add filler. here it is after drying, adding two more layers of polyester filler to cover unfilled areas and then filling small imperfections with putty and resanding. unfortunately, because of the shape i originally bent the tailwheel wire, this bracket ends up being much thicker than the prototype. if i had it to do over again, i think would try to bend some thin mild steel into the shape of the bracket and have it function just like the prototype.
< Message edited by tubig -- 6/13/2006 1:45:09 PM >
not much new to report. sanded all of the primed parts. now to fill in the many small depressions in most of the parts, reprime and sand. in the wing photo the depressions show up as the darker splotches.
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Joined: 7/29/2002 From: Fairfax,
VA, USA Status: offline
My favorite part besides gluing my fingers together is mindless sanding. Its good therapy er maybe I need therapy. Great job on the wheels and tail wheel. I would just tear it up so its wire only for me
yeah, no kidding. it took me two days of mindless sanding for the wing and other parts. then i'll have to do it all over again after filling dents and repriming. this is my least favorite part of building.
i filled in the small depressions in the wing and other parts with Bondo Glazing & Spot putty and reprimed. while waiting for the primer to dry i went back and finished fine tuning my muffler installation. i just had to shorten the bendy pipe by about 1" and added a short piece of silicon muffler extension to the end. after getting in the right position i added the rubber clamp screwed into ply plates on each side of the engine box. at this point i'm not sure if the rubber clamp will be able to withstand the heat on the muffler. if not i have some other nylon clamps that may work better.
at first my plan was to have the flap moveable but now i think i'll just glue it into position (for now it is just placed into position).
Posts: 177
Joined: 7/30/2002 From: Chantilly, VA, USA Status: offline
Tubig I use one of those silicon exhaust extensions on my RCV 120 and it melted. However I did not have the bendy pipe extension. There may be enough heat disapation there . Just look out for the end. Model looks awesome. Break in the RCV with 3-4 tanks at least before you fly it.
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All Forums >> RC Airplanes >> RC Warbirds and Warplanes >> RE: BT Bf109E-4 
RE: BT Bf109E-4 - 
then i applied masking tape to a thickness of slightly more than 1/32" to outline the marks and then cut out a portion of the tape down to the last piece so as not to interfere with the door. i also put several coats of mold release on the doors to prevent the resin from sticking to it. then putting the oleos back in the wing i mixed up some resin and balloons and put a bit on the oleo then put the gear door on top, taped it down and turned the wing over right-side up so the mix would settle toward the door. 
