RC Tank Warfare community hobby forum

Thanks Barry,

In the following two posts, i am presenting the spade elevation mechanism.

The M12 rear spade is equipped with a winch on the right side that is operated with a manual crank from the fighting compartment. It controls a metal cable that goes through a set of pulleys at the rear attached to the hull and the spade.
As this is a detailed scale model in addition to being an RC model, I need all details to be authentic. I wanted to install inside the hull right side the small RC winch below with the cable that would run through the upper hull and through the manual winch, simulating the manual cranking as the spade goes up and down. However, i did not realize earlier that this little winch is so powerful. One imperfect use of the winch using the RC control or an issue somewhere in the end to end system and the whole elevation system could be destroyed. You will see down below.
First thing to do was to create a working manual winch, whether it is operated by the RC winch inside the hull or manually with the crank using fingers. Vandra provides 3D printed set of parts for a non functional winch, and which has limited resemblance to the real thing, as shown next to the 1/35 kit, which is also incomplete but at least resembling. I therefore had to create the winch from scratch.
This is the drum. I used a gear taken from an old turret pellet shooter i had in the scrapyard, with some metal tubing and plastic.
The created the working mechanism with a pinion gear attached to the crank. I reused a section of the Vandra part for the arm.
As shown below, the cable uses a string of pulleys at specific locations on the hull and spade, with the end point of the cable on the left side of the spade. The whole mechanism is therefore quite fragile for RC purposes.
View of the first pulley, its a double wheel pulley with the cable running through the middle. The cable goes up and down as the spade is raised or lowered.
Working pulleys are created using simple material, replacing the 3D printed static ones provided by Vandra.
And this is the spade elevation system.
Continuing on following post

View of the raised position. When raised, there are two locking bar with hooks that needs to be pulled up and attached to their anchor points on the hull. Notice position of the cable on the upper pulley.
Close up on the hull main pulleys, created with the proper shape and attachment points.
First pulley on the spade. You can see the attachment point for the right locking bar.
The spade is lowered or raised by manually turning the crank slowly on the winch, while carefully monitoring the cable on the spade pulleys at the rear. As the weight of the whole spade is no way near the real things, and as the little pulleys are light and not as precise as they should be, the cable gets easily pulled sideways and stuck, at different places every time. Operating the RC winch to the cable would certainly tear different parts of the spade elevation system at one time or another. I determined it was too risky to leave it on. So, i reluctantly decided to switch to the manual mode, like the real thing, and remove the RC winch from inside the hull.
Left side with pulley number 2 on the spade and number 3 on the hull, and the end point on the spade.
Overview of the pulleys and cable.
You can see the little hole through which the cable from the internal RC winch was coming out, doing a few loops around the drum and then going towards the back. As mentioned above, it did not work out for me due to the fragility of the pulley system of the M12 design. Maybe someone with better skills could make it work perfectly but i preferred to keep it manual to safeguard the model. The RC winch was too powerful to trust. There was also difficult to make it stop at the precise position needed. And the travel lock bars have to be manually positioned also.
And one last view for Herman who seems to like the Canadian landscape in winter.
Next step, rear mud guards and tail lights, then detail the top of the upper hull sides. Getting towards the finish line here.

Regards, Louis

That's quite the system there and you did it justice. I'm sure with way it is designed the real crews of the M12 clothes lined themselves on those cables on more than one occasion.

Magnificent.............
That pulley arrangement is a work of art, and I can see why you would not want it to be powered.

Thanks for the landscape shot!...............its 31C outside here
I show the kids what Canada looks like in real life winter ! "dad, why dont you move there & build models"

Dear God!

Louis has now mastered rigging! What's next!?! Stunning work as always!

Cheers,
Eric.

Thank you Tankme, Herman and Eric for your encouragements. Yeah, not a fan of rigging on RC tanks, but looks good.

Continuing with the build, with a short Youtube video of the model in action at the end of the 3rd post.

The Vandra rear mud guards are too wide, too short and don't have the right shape.
New ones are done in plasticard. In order for them to keep their shape, i gave them an internal structure that does not show under an thin plasticard overlay.
They are mounted on the lower hull in order to keep the upper hull removable. Their shape sliding under the fender does not allow them to be installed on the upper hull. The support bracket was an issue though.
They are given the steps seen in references. To keep the hull removable, the tip of the bracket needs to remain unattached. Care is required when putting down the upper hull.
All the details on top of the hull needed to be redone for accuracy, including the cleaning rods that look much better in brass than the resin blob provided.
One of the rod is shorter on purpose, seen in reference.
What i think are fuel tank vents were also redone, replacing the 3D printed blobs.
The resin fuel caps were removed and replaced with Mato metal fuel caps, augmented with some brass rods for details and repositioned at the proper place on both sides.
The M12 now features a full load of ammo.
Continuing on following post.

Rear lights LEDs have been wired. Ammo are just temporarily installed with a small drop of superglue, until painting is finished.
Noticed the bracket to secure the ammo rounds in place.
I noticed later that the tip of one of the ammo round on the right was damaged and need repair. I need to remove them all anyway for the painting.
Overview of the fighting compartment.
The fire extinguisher stand on the right was fun to build. I do have an extinguisher that fits it but it seems to have been lost somewhere on the messy workbench, can't find it right now.
Th rear is mostly finished.
The pin going down on both sides is called a sponson brace. There is another metal plate that need to be aligned with it and attached to the lower hull, not yet in place.
continuing on following post

Head light LEDs have been wired.
Final overview of the electronics under the hood. The Heng Long T90 short battery fits the small compartment above the recoil servo.
Overview of the model as it stands today.
View of the rear mug guards with the spade in raised position.
Short YouTube video of the mostly completed model in action. The spade would need to be firmly dug in in order to provide support for the hull, but you get the idea.



Next step, a final walk around to add the missing details, such are storage boxes on fenders, tools and tie downs,

Regards, Louis

Louis!
All of the Kudos from me for the day, Doc. Another rare piece of Armor brought to Life in a museum grade quality Build.
regards,
Painless

PainlessWolf wrote:Louis!
All of the Kudos from me for the day, Doc. Another rare piece of Armor brought to Life in a museum grade quality Build.
regards,
Painless

Thank you Painless, as you can see, i am a big fan of American Armour.

The following 3 posts are to finalize the construction of the build, with the remaining accessories and tools.

Seen below are the Vandra provided boxes and tools, compared to their Academy 1/35 equivalents. There are major differences between all components and they all have issues.
Starting with the box for the grousers on the left side.
I used the Academy box for size and shapes extrapolation to 1/16. Sadly, I noticed later on that i should not have done that without checking against references. The box ended up to be on the short side by a few mm. Not dramatic, I decided to live with it. I also did not repro the grousers as this box in wartime reference pictures seems to have been mostly used for general storage instead.
The two boxes on the left fender also gave me issues. Reference pictures also show variations of these in terms of details and orientation.
I decided to reuse the small Vandra box, although i had to shorter it dramatically as it was way too high. The larger one should be more square and needed to be completely redone.
These bizarre things seen deployed under both tracks at the front are called "Collapsible chocks" and used to stabilize the tank prior to firing.
These are stored on right front fender as shown here on the Aberdeen M12 prior to its restoration. They seem complicated at first but after some analysis of pictures and study of the 1/35 kit, they are simpler than they look.
continuing on following post.