1:32 Trumpeter TBM Avenger Build

[Crimea_River]

Good attitude and I really like what you did with the engine. Looks really good now.

On the Avenger, the prop plane was 2 degrees downward from the horizontal datum, hardly enough to notice on your model.

 

[vikingBerserker]

Man, that kit has some nice detail.

 

[Builder 2010]

2 degrees wouldn't show up. In the drawings I looked at it looked like the thrust line was horizontal with the center line. If I was making a scale RC plane, that 2 degrees would make a difference in trim, I'm sure. It has great detail, but I have found in other Trumpeter kits engineering problems that never appear in Hasegawa or Tamiya. This was a kit that was produced like 10 years ago, and I'm sure that Trumpeter has evolved since then.

 

[Wurger]

 

[Builder 2010]

Haircut day and other errands so not much time in shop. I did paint the new exhaust extension and touched up the remaining pipes. I added some mounting flanges for the cowl.

The fellow who's interacting with this theme on another Forum (Worldaffairsboard.com - Modeler's Forum) is the owner of a real Avenger which he is restoring. He says all the cowl parts are held on with Dzus fasteners and they are not hinged but come off entirely for service.

Lastly, I wrestled a small piece in place that joins the fuze halves at the front edge of the bomb bay. This is a good example of adding to parts count where it adds no value. Instead in made joining the fuze much more problematic. I had to squeeze the fuze together with lots of rubber band tension and then use lots of CA to get the joint to hold the fuze together. It should have been cast as part of the fuze. Furthermore it would have strengthened that very narrow part at the cowl which, as you can see broke again. I repair it again after I do some filling on the new part. In front of this part goes a bottom cooling flap that I'm gluing in the closed position. That too could have been made part of the fuze casting. Extra parts count is only a benefit when it adds detail WHILE NOT DETRACTING FROM BUILD CAPABILITY.

The brass exhaust pipe looks as good (if not better) than the plastic one (on the right).

I may have made the mounting flanges just a bit wide, but if they're too close to scale size, they almost disappear. Sometimes details need to be exaggerated a bit to be seen. The TBM owner said that he was surprised that Trumpeter added raised rivets on the cowl flaps. On the 1:1 TBM they're flush rivets. Speaking of exaggeration. Those rivets would be close to a half in high. Fastener holes are 0.021" = .67" in full size, which isn't too big.

And here's that pain-in-the-butt part that should have been molded in. I had to pull at least a 1/16" to close it up enough to get it stay in the opening.

The part is not situated well and will need more filing and filling tomorrow to get it right.

The second piece went in better since the first one was now holding the fuze together. All this messing with the rubber bands broke out that filler piece I made. AND that piece was too long when the fuze halves were pulled closer together. That's why it broke out. It was bending way too much. Building a model airplane shouldn't be this hard!

 

[Tony Hill]

Nicely done.

 

[Wurger]

 

[Gnomey]

Lovely work so far!

 

[Builder 2010]

Thank you!

Good day/bad day...

Started with finishing up that repair in the lower fuze front. I rebuilt that missing section using a piece of solid styrene shaped to the curve. This was a much better solution than the thin piece. It had much more surface area for gluing and after sanding, fits really nice and restores that lower curve. It does not interfere with the cowl attachment.

I then put some filler on the other bottom panel. It took two appications to get the contours right. I redrilled the rivets after I finished filing and sanding.

It doesn't look like much, but should be okay with paint.

I started completing the fuze details with the application of the glazing using Forumla 560. This PVA cement doesn't craze or fog clear parts. It's not as strong as solvent cement, but much more well behaved.

I have Eduard's masks which will be applied shortly to protect the glazing during the rest of the assembly and painting.

Next up anti-glare top of the instrument panel with some clear gun sight parts. The little tiny round lens dropped into the hole without problem, but the slanted beam splitter didn't like my tweezers. It launched once, but didn't make it to the quantum rift and I found it. 2 seconds later it launched again, and this time it was vaporized and gone from this universe. I made another one out of some clear sytrene. These were both attached with 560.

Onward to the wings. The kit includes some PE strips that provide an edge extensions on where the folding wings will overlap for aerodynamics. The usual PE problems were there but I prevailed. Clamping and pre-bending helped along with accelerator.

Lastly, I started working on the control surfaces with the ailerons. Again, the darned rift got a part. There are little nylon pieces that provide the axle for the PE hinge parts so these surfaces can move. The first aileron went together well and made me a little over-confident, the next one had a nylon piece that hated the tweezers. Again, it flipped out and I found it. It must have been unhappy and again, in a very short time it flew out again and man... it was really gone. I searched for 15 minutes and got nowhere. It's a part I can't scratchbuild so I just left that hinge (middle) off, and that will be that. Bummer! Since the parts go in from the inside, even if I ever find it, I no longer can get it in place. Again, sometimes the engineering on this kit is just a bit too tricky. Tamiya doesn't do it this way.

I'll keep going on the wings tomorrow.

 

[fubar57]

Fiddly but looking good

 

[Wurger]

 

[Crimea_River]

Like the details.

 

[Builder 2010]

Fiddly is right!

After taking a bottle of Formula 560 back to the store where I bought it and getting another (it was solid as a rock), I got to work on the wing-fold mechanism. I had read in another build that the nylon hinges and the steel hinge pins did not fit well. Nope! They sure didn't. The pins are 1 mm. and the holes have to be at least 30% bigger than that. It makes the wing folding very sloppy. So I decided to make brass bushings and use brass pins. At first I tried using K-S tubing with a .062" i.d., but was have trouble cutting off a piece that was only .047" long (the thickness of the hinge plate). It meant having to machine them.

I first had to adjust the centering of the tailstock. In the little TAIG lathe, the tailstock is on lateral ways clamped by a set screw. It was a bit off center, just enough to cause my center drill and subsequent drills to wander off-center. I drilled the i.d. first with the .032" drill for the brass wire I was using for the hinge. Then I machined the i.d. back just far enough to part off the first one. I found that if I machined too much, it got a little fragile and didn't cut off so well. But using my parting tool wasn't working so I used the digital caliper to space of the .047" and used my newly acquired ultra-fine razor saw to part of the piece. To keep the little tiny bushing from going into the Rift, I placed a piece of brass rod into the hole so the part off bushing would stay put. This worked great! And I lost no parts for the first of the two assemblies.

Here was the first bushing pressed into the hinge.

Here was a bushing after separating it from the rest of the brass.

Here was one half of the hinge with both bushings in place.

And the assembled hinge with a temporary pin. The pin will need to be cut to length. The hinge moved smoothly with no play at all. It will make it so I can actually operate the wing folding without worry.

Tomorrow, I'll machine another four bushings and assemble the second hinge assembly.

 

[fubar57]

Fantastic. With your skill on that lathe, all that plastic piping and valving(?) begs to be replaced

 

[Wurger]

 

[Crimea_River]

Nice, and with Geo!

 

[Airframes]

Agree.

 

[SANCER]

Something happened with the photos ?, you can not see them ...!

 

[Wurger]

This is a problem with the photobucket site. Either the images were deleted or the site is off line at the moment. It happens to posted pics in a such way often while using the site for hosting of your files/shots etc....

 

[Builder 2010]

Eduard has a little bit of PE to make the hinge lock mechanism more detailed, but I haven't thought about replacing all that piping. It shouldn't be hard to do, and it's very visible. Maybe I'll take a crack at it. I have to ask my real TBM owner to take some detail pics of that area.

Thought about machining more bushings and decided to try again with tubing to modify the right wing's hinge. This time, instead of attempting to cut a tiny piece of tubing 0.047" long, I used the nylon hinge itself as a guide for the razor saw. I pushed the tube into opened up hole until it reached the other side and sliced it flush with the hinge. A light touch with a fine file squared it up.

That was for the outer hinge lugs. For the narrower space for the inner hinges, I just put the tube in to fill the entire space and again sawed it off at the hinge. The end result is a very clean installation and it was much, much quicker. The K-S tubing i.d. is sized for the 0.032" brass wire.

Next up was to build the wing machine guns. There's a little Eduard etched plate that replaces the dubious details on the receiver top. One of the easiest PE jobs on the plane.

I then assembled all the parts making up the two guns. Only challenging part is the three-piece barrel. There's a long extension, a transition piece and the gun that get glued together. Gun must have been pretty accurate with a barrel that long.

Now onto some more challenging PE. Eduard provides a whole suite of PE to simulate the real look of inner wing sheet metal. All of the exposed surfaces are covered with etched sheets and then all of the ribs and angles are replaced/added to really jazz this part up that will be seen when the wings are folded.

This is what it looks like with the wing skin in place (no yet glued). To me, doing this kind of detail work is what PE is all about. You simply can't replicate the delicacy of an aircraft structure with the thick plastic wedges in the kit. I really was surpised how well all of this metal fit and I made good use of my folding apparatus to make clean folds on all those pieces. There was another piece of folded PE on an inside wall of the wheel well in this same piece, but on the other (not shown) side.

Monday, I'll do the same magic on the right wing. It's nice to get one under my belt since I now know how it all goes together. You must make sure you align the tiny engraved grooves on the bottom and back plates. The angle PE sits in these grooves with helps align them and provides more surface for the CA to hold. When I first installed the back piece, it was off slightly and the grooves didn't align. I popped it off without wrecking it and got it aligned correctly.