KV-2 MT1 project

[Shotek]

nobody has advice, where to possibly order separate gearboxes please?

[tankme]

The ones I use aren't planetary, but I've been quite happy with the power. I use the "slow" 1/56 ratio Heng Long fully enclosed CNC gearboxes. I can post of pic of them installed when I get home tonight.

[Shotek]

thanks,
If you dont mind, I will be happy to check your setup.

But still..., now I have already ratio 1:100 and tank is still too fast for my taste.

So I was wondering, if there would be an option to order just gearbox eg. 1:200, just to swap them and keep the motors. Those current ones are strong enough IMO, since I have them in my T34 with 1:30 gearbox, but there's additional reduction at final drive aprox. 1:3, so it's running fine even in offroad conditions.

I can order whole gearmotor set with 1:200 for sure.
Just dont want to spend money unnecessarily for motors, which I already know I cant use, just for sake of gearbox carveout if you understand what I mean...

[tankme]

These are the ones I use, but they aren't super slow. With any of the modern electronics you can make them run slow. I did have to drill some acess holes in the bottom of the hull to be able to screw in the mounting screws as they mount from the bottom. So if you want a super water resistant solution mine isn't it, but the holes can be sealed up with tape when not needed. They aren't necessarily cheap either.

In my SU-152:

In my KV-1E:

These are the Heng Long CNC slow 1/56 ratio gearboxes with the shorter 49mm shaft to fit the Taigen sprockets. The HL KV sprockets would need the longer 59mm shafts.
The offset of the Heng Long sprocket is different than the offset on the Taigen/Mato sprocket. I'm using the Mato/Torro tracks and sprockets.



Link to order:

https://www.aliexpress.us/item/32568019 ... bPs7dcbsFN

[Shotek]

wow, what a nice and clean setup! thanks so much for your efforts and sharing...
I'm also jealous, because I'm not an expert on cables and their arrangement

My goal is just a combination of engine and transmission that won't need too much software damping
This is of course possible, but I think it has a negative effect on torque and smoothness at low speeds.

Simply put, ideally the engine should be spinning at maximum rpm at the tank's intended speed and the mechanical gearing will take care of the reduction completely..

[tankme]

My goal is just a combination of engine and transmission that won't need too much software damping
This is of course possible, but I think it has a negative effect on torque and smoothness at low speeds.

Simply put, ideally the engine should be spinning at maximum rpm at the tank's intended speed and the mechanical gearing will take care of the reduction completely..

[tankme]

My goal is just a combination of engine and transmission that won't need too much software damping
This is of course possible, but I think it has a negative effect on torque and smoothness at low speeds.

Simply put, ideally the engine should be spinning at maximum rpm at the tank's intended speed and the mechanical gearing will take care of the reduction completely..

That's the tough part. Most gearboxes for our tanks are not designed for scale speeds so if that is what you want, it's a bunch of experimenting. Experimenting costs money. A lot of folks don't care about scale speed because they also battle their tanks. The Clarks and Tamiya tanks slow down as they take hits so you kinda want to be just a little faster than real life in those cases or you are crawling after just a few hits from the IR LEDs.

[MITCH]

Hi, the best kind of gearbox is the Modelcraft, https://www.conrad.fr/fr/p/modelcraft-r ... ewQAvD_BwE
You only have to change the motor for a 540 45t and your kv2 will be slow enough and will be able to climb the trees

[Shotek]

Thanks for advice guys !

Since my aim is model speed, I want KV to crawl super slow.
So I have already ordered a bit slower gearmotors today:
Modelcraft RB350200-0A101R, 12 V, 200:1
https://www.conrad.cz/cs/p/motor-s-prev ... dYQAvD_BwE
and
MFA 919D1481 12 V/DC 148:1
https://www.conrad.cz/cs/p/mfa-919d1481 ... 22366.html

there's also plan to experiment further with fitting following motor in case of need..
Spektrum SPMXSM5803 Firma 540 80T
https://www.spektrumrc.com/product/firm ... M5803.html
it has 700RPM/V which is quite good IMO

So I am almost sure I will find good combination thanks to that.
Most of the spare parts I can safe for the future projects, just maybe except those weak original Modelcraft motors, but maybe for some less demanding service will be usable too...

In any case, if not, there are far worse things happening in our lives, right?..

[MITCH]

If you want your KV very slow, you can do that:

You only need a second pair of gearboxes, you cut them to use less gears.
The only risk is that the pin on the output shaft will shear... and it happens!
That's why I prefer the version with the 540 45T, otherwise you can use 55T or more if you like
https://www.youtube.com/watch?v=3NBcxxH94TU&t=34s
And if I use the modelcraft HQ, it's because it is very, very silent!