RC Tank Warfare community hobby forum

Anyone change standard 3.1 or 4.1 gearboxes from torro/hl tank for this extra 5.1? Example:

https://www.rctank.de/Panzer-III-51-PRO ... hort-axles

I have 3.1 in my PZ3 and he is much to fast. This 5.1will reduce speed enought?

Hi. You are quite right, the 3/1 gearboxes are far too fast,
But over the years people on this Forum who expressed a view have usually suggested that the Taigen 4/1 gearboxes are better suited than the 5/1 gearboxes,
But if the 5/1 is the only choice you have then yes go for it,
Certainly it will be a marked improvement on what you presently have.

Now i saw that my 3.1 gearboxes have 13000 r per minute speed, and this 5.1 has 17.000 per minute. I think 5.1 is not so slow with fastest motor

It all depends on the actual gear ratio, the higher the actual ratio at the sprocket, the higher the torque at that sprocket. Therefore a more powerful motor is needed, sometimes they have a little extra RPM on the motors to compensate for the higher final gear ratio.

I used the 5 to 1 black steel gear boxes in my taigen Panzer 3 and it ran great. Just don't try to use them in a heavy tank, like a King Tiger.

If the 3:1, 4:1 and 5:1 refer to the gearbox final ratio then a 5:1 will be the slowest but the more powerful so best for heavy vehicles (note heaviest, not necessarily biggest!).

However, you need to factor in the motor spec. We seem to used brushed in tanks to keep the prices down. The revs of a motor is governed by the number of turns or winds of wire around the armature segments. The more turns the higher the torque and the fewer the turns the faster the revs. I'm not sure I've ever seen motor specifications quoted in gearbox/motor combo advertisements.

So.....without knowing more about the motors that are used you can only go by experiences of others. Unfortunately, the RC tank hobby has always been more about model making than the technical aspects. Its not until you get to RC car racing that this reverses but then a good race motor will cost more than a Heng Long tank!

Sadly the 3:1 etc is meant to refer to the number of gear train axles, sadly even that's inaccurate, and it doesn't always tie up with the number of gear trains either, it's a total stupid system, and it's about time gearbox manufacturers stamped the actual gear ratio on their boxes. Heng Long are 39 point something to 1, and I believe all the others have a larger ratio than Heng Long.
I'm sure it's the cheaper Taigen box that is called 4:1, but has the same number of axles and gear trains as the Heng Long 3:1's, see what I mean by how stupid it is.

Really?? That sounds ridiculous! I must check the actual ratios when I've got a couple of hours to spare. I know that when l replaced my HL Tiger 1 gears/motor set with the 4-1 Taigen type it improved slow running. That was a simple swap and only required drilling a couple of holes to give clearance to a couple of wider screw heads and l seem to recall drilling out the drive wheels to take the fatter axles.

Another important factor that l didn't mention is the diameter of the drive wheels. The smaller the wheel the slower the top speed but the greater the torque.

First and foremost, give no credibility to the "3:1" and "4:1" labels, and even less to the "5:1" label, as I remember when Erik Edwards made that one up out of whole cloth. I tried to convince him to push for "dual ratio" gearbox, as you really can change the ratio on those (I might even still have some of the special milled axles if anyone needs any) but nobody listens to me. It all started with the 3:1, which was before my entry to the hobby (2013, but didn't join here til '15), but the best explanation I could get was that when they came out they were supposed to be 3:1 as compared to Tamiya. Then came 4:1 and they needed a name and had added a gearset, so they called it 4:1. I think the actual ratio on that is around 39:1. In other words, the pinion has to turn 39 times for the axle to complete one revolution.

The "5:1" used to be made in brass and they went out of production right as I came into the hobby. I have a few sets and won't part with them for nuthin'. Up until then gearboxes had been made in plastic or zinc. Then came the steel craze. Great upgrade for the 3:1 and 4:1 GBs. So great that they quit making brass GBs and converted them over to steel. Bad Move. For some reason the steel just needs huge amounts of power compared to brass. Don't ask me why, I just know its true. I've been hoping they'll just go back to making them in brass, but no joy so far.

So the steel "5:1" GBs are good for a Panzer III, a Stug III, maybe the PIV, etc. I tried a pair in a King Tiger with a 2S lipo and fried a stock MFU. But here's a video of my Taigen Metal Edition Panzer III with Black Steel "5:1" gearboxes. It's on the V2 Taigen electronics with a flysky i6 and a 2S lipo battery.



Hope that helps.

General Jumbo01 wrote:Unfortunately, the RC tank hobby has always been more about model making than the technical aspects.

ROFL.