Hello! I'm new, and have had a strange problem occur with one of my tanks, a Torro Jagdtiger. The left side gearbox has become unusable; power is transmitted through the gear-train, but the output shaft spins almost freely through the black gear on it. If I remove the left side track the sprocket can spin with application of the throttle, but as soon as anything attempts to stop it, even a lightly gripping hand, it stops. From what I can tell a small pin which holds the black gear on the output shaft has broken. I am fairly sure that the gearbox must be replaced, but I have decided to ask here, as there seems to be a lot of knowledgeable people here. On another note; I've got a good few tanks now, 6 of them if you include the aforementioned JT. I would post pictures but I understand that you need a minimum number of posts to do so.

It may be a small set screw that loosened up, or if it is a pin, you could try to replace it. Replacing the whole gearbox is not that expensive or technically difficult if you go that route. Tanks need constant tinkering to run reliably.

Where are you located? If you're close I might be able to just send you a new axle shaft with gear attached. It's not a very big job to swap out an axle shaft. I've done it plenty of times when I needed 58 mm shafts and only had 48 millimeter gearboxes.

Sorry to get back so late, I got a new computer, been setting it up, but I'm in Montana, but a new axle would be a great help. As it goes I have the gearbox mostly taken apart so I can find out what happened with it.

post pics of what you find. Sounds interesting.

I have pictures, but am unable to post them, it says I need 10 posts to add pictures. Great rules! But I've found that the gear is held onto the shaft with a very small pin, which has broken in 2 places. I am unable to repair it as of yet, due to the fact of how small the pin is, it seems to be about 1mm, 1.5 at the largest.

Try to find piano wire at a local hobby shop the right diameter. It will make a good gear pin. You will need a very good pair of dikes or wire cutters to cut it though.

Just a heads up we did revise the pins on the final drive shaft where they can now be swapped and are no longer held on via a pin.


Old on top, new on bottom


New disassembled


Closer look at the pin retention system
Some of the new gearboxes will have them already installed, some of the older style zinc and v1 gearboxes are still using the old system. The new system seems to have less issues with the final drive shaft breaking from what I've seen. This change happened a few months ago actually.

Erik, the JT uses the 58 mm shaft, right? I might have one at home I can send him, I'll check it out when I get home from work.

Glad to see that the shaft design was revised! On a tank as heavy as the JT it quite needs them. But I'll most likely see if I can get some piano wire to fix the shaft, mostly just to see if I can at all.

Yup, takes 58mm for the JT chassis. Where is the Hetzer?
It wasn't a big problem on any specific tank really, just one more little thing to improve that helps all the gearboxes. I only had a handful of complaints but everything gets passed on.

Let me know if Crius can't take care of you, I got a ton of them of all sizes.

I think the main reason why the pin in mine broke is due to the extreme amount of pea gravel and other various small rocks, on my HL KT I've had rocks wedge themselves into just about every part of that tank, I've even had them in the idler wheel before. But I'm going to see if I can find some piano wire or something like it as Rich suggested to try and fix it. And if that doesn't work then I'll ask around here for some spares. But I am quite happy to know that the people here are friendly and helpful, always a good thing in a hobby with as much tinkering as this one.

Yea this forum is a good one, definitely my favorite.

She's alive and well. I just got the skirts on her so she's almost ready for paint.

I always like them with the skirts off, but to each his own

The skirts aren't permanently attached and pop right off if you want to run without them. I think I like it better without skirts, too, so it's nice to have the option.

I wasn't talking about the tanks but yea the Hetzer is looking good!

Heh Heh

I actually like the skirts on the Hetzers though -

A hetzer! But anyways, I managed to "fix" the pin problem, but it's very haphazard, as I've just used a cut down track pin for my HL KT, and some tape. To which my question is now, Crius, or Erik, or anyone really, could you supply me with the shaft, or shafts?

I think this is the set you need, perhaps Erik can confirm that? The short shaft is only in the photo to demonstrate that the shafts with gears are the longer, 58mm shafts, and of course the gears are black steel.

Those look exactly like what I need.

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