RC Tank Warfare community hobby forum

The Thingiverse website has a 3D-Print set of files for a 1:16 scale T-35 A WW2 Russian tank. Sometime last year, I showed the set to a friend who produces 3D-printed items and idly asked what it would take to do this. It was an academic question on my part. However, two weeks later he said "let's do it"! He knows printing, I know r/c tanks.
It's been a long term project, but we're at the point that it looks like it will work, so I've decided to document some steps we've taken and share future ones.

Bob! This will be interesting!

Our first concern was whether we could even get the tank to move, so we worked on the hull, suspension and tracks.
Here are the four pieces of the hull, one upper suspension part, and the motor/gearbox/sprocket assembly. I placed a Panzer 1B in front of it for perspective. I'm using a Heng Long power setup with upgraded motors. (The little blue beacon was to let me know power was on, since there was no sound at that time.)

The next step was to finish the running gear on one side and run tracks on it. The tracks were critical, if they didn't work, no need to go further. We tried a number of materials and printing resolutions. Most worked, so we were happy. .032 wire was used for pins. I applied a small amount of cyanoacrylate glue on the track edge to secure the pins.

Checking the mesh with the sprocket: Checking different print configurations:

One side completed:

I had to find a suitable color paint. Rattle cans or airbrush jars would have been too expensive, so I found an "Italian Olive" hardware store spray that I tested on the side. I made extensive use of 3mm socket head bolts and nylon lock nuts. That way I could remove parts for painting, repair or maintenance. Lots of fun assembling track links. 131 per side, five feet long!

Here's a view of the interior at this point:
One goal of this project was to see if I could use Heng Long components for power and control. 6.1S board, HL speaker and 2S Li Ion battery. Later I upgraded the battery to a 2S 7000mah Li Ion. I figured there would be less voltage sag under load with the higher amp/hours. Plus, some of the HL 1800's would only give me a few minutes of running with this beast!

With this done, I could run the tracks on the wheels. Good so far.

Okay, one side runs, let's do the other:
And now, fingers crossed, a running test. Will the motors be strong enough to move the chassis? And more important, will the absurdly long track base be able to turn?



Yay! So far so good. (That became my mantra for this project.)

So now it was time to put together the tanks structure itself. I don't know printing, but I'm told a new nozzle had to be installed on the printer to enable a higher resolution print. Resin was used for the topside components, to reduce rough textures.

First up was the main cannon parts. Turns out they were made with a recoil capability along with elevation. One thing with resin is that there is a lot of sanding and filing needed to make parts functional.

Other topside parts dry fitted. Here's a view of the turrets' interiors. Now I have to start thinking about what animation functions will I be able to incorporate.
Here is an overview of some of the topside structure pieces:

Of course the most important animation would be the main gun recoil and elevation. I used micro servos for both. I also installed a muzzle flash LED, one of the circuits on the Heng Long board. I sprayed an orange transparent paint on the white bulb to minimize the "cool" color.