RC Tank Warfare community hobby forum

Hi everyone,

Start of a new project, a simple RC conversion of the static 1/16 scale Takom M50A1 Ontos ("the thing" in greek).

I had the Takom kit on the shelf for maybe two years now. When i opened it the first time, the complicated suspension and the rubber band tracks did not encourage me to pursue a conversion. However, i relooked at it and concluded that a working suspension for such a small vehicle is probably not required. With its light weight, super wide tracks and low ground pressure, a working suspension would probably not even be activated.

So, with a total RC conversion budget of around $50 dollars, i decided to give it a try, the risk is low. Besides, i like to see things that i have not seen before so this is a good opportunity to have some fun.


Seen below is a M50 Ontos at the US Marine Corps museum in Quantico during my visit there almost 15 years ago. Nice museum with realistic and complex displays.


I was looking for something different to build, and this is definitely a good choice.


In service only with the US Marine Corps, it served well in Vietnam, providing valuable mobile fire support to the infantry. It is armed with 6 M40 106mm recoilless rifles on a small turret, and one M1919A4 machine gun.


The tracks are very wide, consisting of a band with metal cleats.


The Takom kit. I love this brand, providing unique and affordable 1/16 vehicles to the market instead of just issuing the N variation of German stuff.


The two part rubber band tracks... It is obvious that no after market company would ever offer a replacement for it. Actually, not a single after market item can be found for the Ontos.


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The two joints in the tracks are an obvious weakness point. The right glue needs to be used.


The complex suspension parts has large components. There are no torsion bars or springs. I did not find a way to make it functional. So, this vehicle will have a static suspension. With the vehicle super low ground pressure, complicating the RC design with all kind of working suspension gizmos would have created weaknesses that are not needed.


Good roadwheels and thick plastic sprocket, its promising.


Comes with a crew figure.


The kit comes with interior, which will sadly not be used because the RC electronics will take all available space. A big component of the build will be to assemble the six M40 106mm recoilless rifles coming on many sprues.


The little turret is supposed to rotate 40 degrees. I will try to make it happen. The M40 rifles shall also have elevation and a couple of them shall have flash and sound, without recoil though, its recoilless...


Nice PE sheet, mostly for the ammunition but the engine and exhaust grills are there


Same as the M113 build, a Tamiya twin motor gearbox will be used. Can be found for $10 on ebay.


The small type 130 motors will be replaced by type 180.


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The new type 180 6V motors purchased on eBay for a few dollars. Take note of the codes before ordering as these come in many variations.


They were each given three type 104 capacitors. One between each terminal and the casing, and one between the + and the - terminals. Purchased by the hundreds on Amazon for a few dollars. Without these, the speed control does not work.


The gearbox hole at the bottom need to be enlarged to receive the larger ring at the tip of the 180 motor, otherwise the casing is the same as the type 130 and the motor just slides in place. Black tape keeps everything secure.


And here we have a M50 Ontos powerpack. The main axles are in position A.


The tub is assembled. No issue, fit is good, parts are strait.


The joint between the custom gearbox and the sprocket is always an interesting problem to resolve. After some analysis and investigating various options based on the material available, i have decided to reuse a metal axle extension for WPL trucks, available on Ebay. Then the central section of a WPL tire rim will be reused and glued to the sprocket.


After that, the shafts of the gearbox will be cut at the proper length. As it looked like this would work, i proceeded.


The WPL rims are cannibalized.


Sprocket components are laid out


The WPL central hub is glued to the sprocket, with the hole and screw inserted in the other direction to ensure a complete fit before the glue is set.


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Sprockets are inserted in place, ensuring they turn freely. The Hex pin to lock the sprockets to the gearbox ends up just inside the hull, great.


Axles are cut and gearbox is installed. It was given a plasticard base and screwed in place after some tests.


The gears were soaked in synthetic grease and a plate was put on top of the gearbox to protect the gears and keep the grease from flying away. Suspension parts were built as per instructions.


Other than the idler, all the suspension arms are solidly inserted in the hull, the fit is very tight. They really do not move but they will later be glued in place. For now, i want to keep things removable.


Complex design. The sprocket cannot be removed without suspension 1 also removed. Something to remember for the installation of the tracks.




Everything holds together using a external metal bar that locks the suspension units in place. Instead of gluing this bar, i decided to keep that key part fully removable forever.


M1.4x8 screws were used.


The suspension is in place, and removable if need be until the end of the build.


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For the gluing of the two part rubber band tracks, i looked for a kind of glue that would keep things solidly in place, but flexible. This is a contact glue for the fixing of flexible material, such as rubber, tissue, umbrellas, etc. Fumes were bad. There might be better glues for this job, but this is the one i used. Absolutely need to avoid glues that would prevent the track from bending.


I gave it 24 hours to dry. Joint is good and flexible. The tracks bend easily around the sprocket and idler, and are stronger than expected.


Installation of the tracks by loosing up the idler arm. Oh, the tracks can likely be stretched a bit to get over the sprocket teeth and idler without doing this but i didn't want to take any chances with the tracks. Break one and its game over.


Views of the chassis with the tracks, with the basic electronics thrown in for the test.


Here are two videos. It works well.


Motorization and track testing





Running test. I was concerned about rubber band tracks on a RC vehicle but i am now convinced that this model can be driven anywhere. It won't be a table top conversion.





The model has room for the TK 7.1 control board, battery, speaker, and likely 2 servos for the turret.


This is it for now, taking a short break.

Regards, Louis

Nice subject and great start. At this rate, that's going to be a very quick build. That's something I know nothing about...

I'll be following this Louis with close attention, and your other Takom builds as well to help/give me ideas on my Takom FT17 and Type 94 tankette.
These Takom jewels are:
1. look like a blast to build,
2. the closest I'll get to a kit build since Tamiya is far too pricey for poor me (waah ),
3. a good skillbuilder for 3D stuff,
and 4. as you say Louis, not just another same old same old from the mainstream guys.

Mike.

OHMIGOSH! Louis is at it already, with hardly a breather after the M113! "a simple [year sure] RC conversion of the static 1/16 scale Takom M50A1 Ontos." Remembering the Renwal (?) kit from the 'sixties, I jumped on this Takom kit as soon as it was available on Andy's Hobby Headquarters. I hope to build it static (someday) as I do want the interior. But I sure will be watching with interest and awe.

Look, there's another kind of glue I can buy. That must be about a dozen types now.

lmcq11 wrote: ↑Mon Mar 10, 2025 2:12 pm


Installation of the tracks by loosing up the idler arm. Oh, the tracks can likely be stretched a bit to get over the sprocket teeth and idler without doing this but i didn't want to take any chances with the tracks. Break one and its game over.














Running test. I was concerned about rubber band tracks on a RC vehicle but i am now convinced that this model can be driven anywhere. It won't be a table top conversion.

A member of RC Universe Printed a set of replacement tracks for my Torro M16 Half Track and they work just fine.
Apart from that you have built a brilliant conversion, Very impressed.

These rubber tracks are probably a nice change from those glued together from a thousand pieces