Tamiya 1/35 M113 APC motorized 1974 Vintage >RRC

[modler]

I just upgraded the radio gear in this M113. It now has a sound system and 2 speeds fwd\rev. It can do both high\low speed track pirouette now and has very good track control. I built this for small space operation indoors. It runs off a tiny 1s lipo.

M113 video

https://youtu.be/qfxyJsp0C0s

[xhelfix]

Hey,

realy cool, thats fine how you are bring "live" to this smal one´s

Greetz, Andy

[C.Ellis]

I love it!
What control board are you using to get that scale speed? It's great that it doesn't jerk around like a heng long tank. Just having a model that moves right goes a long way towards its realism. I can't wait to see it painted up and with decals on.

[modler]

Hey,

realy cool, thats fine how you are bring "live" to this smal one´s

Greetz, Andy

Hello Andy, this one took some skill and knowledge in electronics\mechanical to get it to function as you see in the video. This Tamiya M113 has the option for "motorized" single motor only. I modified a Tamiya 1/35 Type 74 Tank dual motor gearbox by shortening the axles and sprocket lock nuts width to fit the M113 Hull. Just the mechanical aspects of this upgrade can be a challenge in a model this size (small). The tracks and drive sprockets are stocks and are from the "motorized" version. I broke one of the outer teeth off the left drive sprocket during the retrofit but it still seems to work well. The non "motorized version has different drive sprockets that are not optimal for full dual motor upgrade.

[modler]

I love it!
What control board are you using to get that scale speed? It's great that it doesn't jerk around like a heng long tank. Just having a model that moves right goes a long way towards its realism. I can't wait to see it painted up and with decals on.

The control board is from a ebay toy 40 mhz 1/72 Tiger tank. I borrowed the electronic circuit board from that Tiger and wired it with micro connectors and tied that into the factory on\off switch. it runs off a 110mah 1s lipo.

The secret to the "scale speed" are impedance matching the motors to the supply voltage. 3.75v, 9~12v 130 motors. these are low speed high torque motors running below their normal voltage level.

The circuit board has sound system\speaker for engine and road wheel noise.

The donor 1/72 Tiger Tank cost $15, or 11.55 pound.

I will take pictures of this circuit board on the next one using this low cost Tiger. The circuit board is very small and only suitable for smaller models with the correct matched motors.


once again here is the video link showing the improved M113 now with sound and 2 speed ESC. https://youtu.be/Uv6y2BjT0EM

[C.Ellis]

Cool, thanks for the info.

[modler]

Put the RunCam2 on the M113 APC for a bridge crossing run, I had to lower the angle to about 20° as the APC has low gradient climbing ability compared to some of the Tanks in my collection.

Hobart bridge crossing video...
https://youtu.be/9p8ZgTIEr0s

This APC runs of a 250mah 1s lipo and is a little slow due to the rare 9v RE-140 motors. I am looking for a set of 6v motors for it as that will give it a reasonable working speed. All though it is a bit slow even when top speed is selected on the TX, it has very good battery life and will even run off a small Lithium Ion cell with these 9v (high impedance) motors.

[c.rainford73]

Really impressive work Tell me more about the sound system used and how you wired it up. Is it from one of the 1/72 donor tanks?

[modler]

Really impressive work Tell me more about the sound system used and how you wired it up. Is it from one of the 1/72 donor tanks?

Thank you for the kind words. I like to share this work with others of like interest. I am a retired industrial electrical\electronic designer\programmer with a RRC Tank obsession that started in 1978. First RRC tank was a Tamiya 1/35 Crusader MkIII. I still have it

Ok, enough of that and back on point...
Yes it is from a ebay RTR RRC model, the sound system is integrated on the circuit board I used from the ebay 1/72 Tiger Tank RRC model. I got this 1/72 Tiger model on ebay with the intention of using its tiny RRC circuit board (with sound) in the M113 APC. This circuit board originally drove a set of coreless motors so the options are limited when using larger cored motors such as RE-130, RE-140. They can be used but the impedance needs to be higher than the normal 3v motors. In the APC of this thread, I used RE-140 12v motors which read ~15-20 ohms on a DMM. A 3v RE-140 reads 1.5 ohm. I am trying to zero in on where to get these 12v motors. I had a few laying around but do not know where they came from. I have not tried a 3v motor on this circuit board but based on my experience I would say it would be risky using those as they would more than likely cause the output circuit to fail due to impedance mismatch.

ok this is a quick response to your query and I will continue soon in steps because it takes a lot of time to explain this stuff And if I spend too much time on the computer the wife feels neglected as I spend a lot of time with this info with others trying to help.

White Table APC reconnaissance mission..
https://youtu.be/-A4OJ0tbNiU

[modler]

I just did a video of the M113 APC on the white table using a very small (100mah) lithium Ion metal can lipo. The Mabuchi RE-140RH motors use very little current at this voltage (~3.7v) and allow the APC to run quite a while off this tiny Lithium ion battery provided it has the proper load. The motors used in this APC match the power load requirements of the Lithium Ion battery allowing the APC to operate longer than you would want to run it in one session

The 100mah lipo shown is from the ebay 1/72 Tiger RRC tank. I will hook it up via the micro 1.5mm JST connector to see how it performs in just a bit.

I use the 1.5 micro JST male\female connectors in all my 1/35 scale models. You can get them on ebay pretty reasonable.

So in this video the APC is powered by the L-Ion battery.
https://youtu.be/-A4OJ0tbNiU