BarryC wrote:Looks like the Vandra kit is made to only "appear" to be an M12
Yeah, Checking dimensions against references like a good 1/35 kit would not take the designer much effort. It would actually be simpler as it would ensure the parts come together at the end, and the accuracy would be ensured.
Continuing with the build.
Looking at the upper hull in preparation for the next step, i saw there is a strip along the hull that need to be reduced from 6mm to 4.5. Its going way too low and it shows when sitting on the lower hull.

- 1/16 RC US 155mm Gun Motor Carriage M12 - Build
Searching through the junkyard, i found an old Heng Long Panzer III/IV gearbox with metal gears, good enough for an M12. Likely some leftover from another conversion years ago. I did a limited refurbishment of the gearbox by replacing the old motors by less older ones, replaced the old torn wires, replaced the tiny type 104 capacitors by new ones, added a third capacitor between the + and - poles. Tests show it is working well, a lot more responsive at low speed. I had to remove 3mm from the main shaft to align the sprockets with the roadwheels, a 1 minute cut with a metal saw and some filing.

- 1/16 RC US 155mm Gun Motor Carriage M12 - Build
Gearbox installed on a 3mm plasticard support base glued earlier to the bottom of the hull. Reinforcement added to the front, providing support for that gearbox screw and also support for the long side covers. The fit of the Heng Long gearbox inside the Mato M4A1 hull is extremely tight. I had to do some surgery by removing anything that was in the way.

- 1/16 RC US 155mm Gun Motor Carriage M12 - Build
The three piece transmission cover provided by Vandra is installed, one of the thing they do well. I know its shape was adapted to fit the Heng Long gearbox and the RC Sherman lower hull. It is out of scope of this project to do anything about it that would make this part more accurate.

- 1/16 RC US 155mm Gun Motor Carriage M12 - Build
The spacing between the sprocket and the hull cover plate is realistic.

- 1/16 RC US 155mm Gun Motor Carriage M12 - Build
No more space issue with the fitting of the upper hull over the gearbox motors.

- 1/16 RC US 155mm Gun Motor Carriage M12 - Build
The fenders at the front need to be flat.

- 1/16 RC US 155mm Gun Motor Carriage M12 - Build
The M3 Lee fenders that Vandra provided for the M12 need to be discarded. References show no embossed stiffeners on them, and the ugly squared holes meant to go around screws for the transmission cover don't fit my project. These fender parts will be replaced by a flat plasticard section of a thickness to be determined.

- 1/16 RC US 155mm Gun Motor Carriage M12 - Build
Looking at the lower rear plate and its angle. The rear of the M12 is totally different that what is normally seen on any Sherman.

- 1/16 RC US 155mm Gun Motor Carriage M12 - Build
The whole Sherman M4A1 rear armored plate with the engine hatches has therefore been removed for a complete redesign, including the idler adjusters. The engine on the M12 is located in the middle of the vehicle, which explains the difference.

- 1/16 RC US 155mm Gun Motor Carriage M12 - Build
Continuing on following post.