1/48 scratchbuilding project; Martin T4M

[ghodges]

Part of scratchbuilding is having to rework and rebuild things along the way. I wasn't satisfied with the original nose I built for the 1/48 T4M-1; so I started over from "scratch" and built what I think is a better one.

The back plate matches the front of the vac fuselage, The front octagonal plate establishes the end of each section as well as gives the front measurement for each. Note the engine with tubing glued to its back that will fit into the nose when done.

Shot of test fitting the engine.... there's some room to move the engine in or out to allow for the exhaust manifolding on the back to be built up later.

As you can see, the original nose had a top panel that was much too wide and each of the other panels weren't as well defined. By building the new nose using flat panels cut to shape I could get the top center panel the correct size and make each one's "match" on the other side of the nose the same size until it was filled in all the way around. Note all of the air louvers on the drawing that will need to be added before I can call the nose "finished".

Test fitting the nose to the fuselage. Although it is slightly larger in diameter where they meet, there's a thin "proud" strip that wraps around the nose just in front of the front cockpit that will help even out that difference. It can't be added until after the fuselage has been glued together.

With some luck this will be the last major "build" job of this project and I can get the vacuform fuselage halves glued together and the nose added to complete the fuselage. Hopefully, after that, the rest will be simply a matter of normal parts detailing, gluing and aligning, and other such "mundane" work as done to complete any other model. We'll see!

 

Gil 

Edited April 24 by ghodges

[ghodges]

3 very mundane pics......

But they show a very MAJOR step forward in that the fuselage halves are together and the first coat of primer applied! It even sort of resembles an aircraft fuselage!

The next steps are to finish applying most of the features that still need to be added to the fuselage, or at least get their areas ready. These are things like the the platform between the pilot and gunner's cockpits, tail plane brace brackets, elevator and rudder control wire holes, the reinforcing strip around the nose, making the windshields, tail wheel socket, etc.

It doesn't look like much, but you can see how much work was needed JUST to make this step possible if you glance back to the beginning. Hopefully I'll make progress at a little better rate from here to the end. 

 

Gil 

[ghodges]

The fuselage is now mostly complete since the nose has finally been added!

The main thing that jumps out in the pic is the bracing strip in front of the first cockpit. I used multiple layers of tape wrapped around the nose to do it. You can also see one of the masks for one of the window openings has come off during handling.

Note the crawl platform that's been added between the pilot and gunner's cockpit. It's just a plastic sheet bordered by upside down "L" shaped strip.

In addition to the nose reinforcing strip, note that I repaired the forward access panel and also added a wire grab handle near the crawl pad.

This view shows the scratchbuilt tail wheel and a closer look at the rear sides shows the reinforcing strips added around the areas for the control wire holes and the tail plane underside brace points.

Next up is another round of filling and sanding imperfections, but it feels good to seemingly be making faster progress!

Comments, questions, and critiques welcome, as always!

 

Gil 

[Jmarc]

NNNNNNNNeat !

[ghodges]

I got 2 more important steps completed today.... I added the vent louvers to the nose and also vacked and built up the engine crankcase cooling cover.

I cut 1/4 round strip plastic pieces to as consistent a size as I could and then placed each one individually.

There's more than 50 louvers on 7 of the nose panels.

Note the the very top nose panel is the only one with a slightly different pattern to its louvers.

I made the form for the cooler cover by sawing off the front of a 1/32 engine crankcase and then vacking over it on my Mattel machine.. The cooling slots were added by drilling and trimming each one.

Here you can see how it fits to the engine, as well as the partially closed cooling slots. The slot doors were made by cutting thin triangular pieces of white plastic tape and pressing them into position on the inside. Each one was then superglued in place permanently.

I've since also primered the louvers on the nose. Getting close to gluing the fuselage to the wings. More pics after it starts resembling an actual model airplane!

 

Gil 

[ghodges]

Piddly, but necessary work continues......

This pic shows the 3D printed Scarf rings bought for this project, the completed engine oil cooler cover (now with back plate). the scratchbuilt tail hook, and though hard to see the 3 windshields made and the tape pattern used to make them.

Here's a test "sitting" of the windshields and Scarf ring. Note that 2 vertical posts have been added to the rear cockpit sides to support it.

Test fitting the tail hook, which has a small wire post on the underside to serve as a locating pin.

Still have a good amount of engine detailing to do too..... but I may just go ahead and get the fuselage glued to the bottom wing just so I can take something resembling an airplane to our model meeting Saturday! More pics then!

 

Gil 

[ghodges]

BIG STEP FORWARD..... the bottom wing and fuselage have been joined together!

I've done the initial filling and sanding, but will wait to do the priming until after my model meeting today. The landing gear and wheels and empennage are all just sitting in position for the pics.

I still have 4 major struts to add that attach to the fuselage and wings, but have finally reached the stage where they CAN be added. There's no turning back now!

 

Gil 

[ghodges]

With the fuselage and wing in the filling/sanding/priming stages, I turned my attention to the engine and the prop.....

For those of you old enough to remember when Saturday Night Live was funny, as Rosanna Rosannadanna said: "if it's notta one thing, it's a somethinga else"!

Turns out the engine I had wanted to use (and every other engine on hand) was `1/4" too small in diameter. That's a scale foot too small! Since no one makes a resin P&W R-1690 that meant I'd have to "enlarge" the engine on hand.

It was enlarged by first removing every cylinder from the crankcase and then installing thick punched discs at the bottom of each one.

This pic shows the plastic sheet used to make the discs and the half round rod used to detail the tops of each cylinder. I used my trusty (and now rusty) old Waldron punch set to do the job!

Since the cylinders were now longer, the original push rods had to be cut away from the crankcase cover and individually installed to fit. Since they'll all be covered by the oil cooler cover, those gaps at the bottom of each one won't be seen.

Once the engine was the proper size and the front and cylinder tops detailed, I worked on the rear side....

The white intake/exhaust manifold ring was made by first drawing it on paper in order to get its 9-sided design and then copied onto sheet plastic laminated to the proper thickness. Holes were drilled in its top edges and into the rear or each cylinder for the intake and exhaust piping. Solder wire was then bent to shape and cut to length to make each set of pipes. Drops of superglue where  pipes join will resemble "welds" after painting (I hope!). By the way.... as for the exhaust pipe arrangement.... I've seen at least 3 different "ways" in various pics and so felt free to make this design with 2 sets of pipes for each side of the plane since I couldn't pin down any "one" accurate design.

The 4 pics above show how the finished engine and exhaust piping looks when mounted. I may add a few more small bolt heads here and there for additional detailing, but it's essentially done.

I had no prop of the proper size either in my spares box and couldn't find one to order either so I "Frankensteined" one from spare prop hubs and blades.

It still needs some cleanup here and there (the blades will be chromed!) and I may also add some counterweights for detail, but it's also essentially done.

I have to say I was a little bummed out when I realized I'd have to modify the engine, but it went much smoother and faster than I thought it would in the end, all of the above work (including building the prop) taking about 4-5hrs.

Now back to the fuselage! As always, critiques, comments, and questions are welcome!

 

Gil 

 

 

 

[Ron Bell]

Could that engine have been more fiddly to do? While doing all that piping where did you get the extra hands/fingers to hold stuff in place?

[ghodges]

That's the nice thing about solder wire..... it bends easily but also holds the shape well. Glue one end into a socket hole, bend, apply a dab of superglue at the next juncture, and keep going from there. It was tedious, but not too taxing from a "holding" standpoint.

 

Gil