RC Tank Warfare community hobby forum

From what I understand as others have already mentioned. 3:1 means it takes 3 complete revolution of the motor to drive 1 complete revolution of the drive sproccket (high ratio) which is good for speed but low torque.

4:1 means it takes 4 complete revolution of the motor to drive 1 complete turn/revolution of the drive sprocket. This means (lower ratio) higher torque but a tad slower. This goes to the rest of the motor gears combo.

A gear reduction ratio is calculated by the number of teeth on each gear!
shaun

Wrong, guys, sorry. I've torn my hair out over this ever since I got in the hobby. 3:1 and 4:1 are meaningless, and 5:1 was made up out of whole cloth by Erik. They have nothing to do with actual gear ratios. An actual gear ratio for these would be (I think) around 56:1. That means that for every 56 times the pinion gear on the motor turns, your drive sprocket makes one revolution (I could be way off on this and it may be as high as 96:1, someone has counted but I can't find the thread). One explanation I heard for calling them 3:1 is that back in the day when Tamiya was the only game in town, someone started making stamped sided GBs and they were supposed to be 3:1 (three times as fast) when compared to the tammy GBs. I still can't confirm that. I refer to them as 3 shaft and 4 shaft GBs. Watch this and it will explain things.

jarndice wrote:A gear reduction ratio is calculated by the number of teeth on each gear!
shaun

Sorry, Shaun, a gear ratio is counted in revolutions. To get extremely basic it's, How many times does the little gear turn to make the big gear go around one time.

Definition:"The ratio of the rotational speeds of the first and final gears in a train of gears or of any two or more meshing gears".
So these 4/1 etc. designations can be misleading or at the very least confusing!

tao wrote:Definition:"The ratio of the rotational speeds of the first and final gears in a train of gears or of any two or more meshing gears".
So these 4/1 etc. designations can be misleading or at the very least confusing!

Key word rotational, as in revolutions. Confusing is an understatement of truly epic proportion, my friend. I wasn't kidding about the tearing out of hair.

The ones they're calling five to one are what I refer to as "dual ratio" GBs because you can switch from one gear to the other at the axle. That was when Erik referred to them as dual ratio but for some reason all this 3:1, 4:1 and 5:1 crap seems to have stuck. The dual ratio are also the only ones that come in a low/low configuration. I guess the main thing is that we all know what it means. The important thing for you to remember here is that the 3:1 give you more top speed but poorer low speed performance due to lack of torque. I run the 4 shaft GBs in almost all my heavies, and the S33 has the brass dual ratio GBs, as does the Jagdpanther due to fit issues with the 4 shaft. Those will go in the Panther G but not the JP.

Hello everyone, thank you for your answers. I go for a 4:1. With Christmas the present for my son and me will come.....

Have a nice day!

Guys can I ask a question are the gearbox motor packages model specific.... Ie tiger ones fit a Sherman etc or individual to that tank ?? Cheers Andy

Spartan tracks wrote:Guys can I ask a question are the gearbox motor packages model specific.... Ie tiger ones fit a Sherman etc or individual to that tank ?? Cheers Andy

Low Profile gearboxes will fit in just about any tank...including the Sherman...High Profile Gearboxes are more limited because of the High mount of the motor....the differences in both is the length of the final drive axle ...Long or Short...that pretty much determines the tank it works in


ALPHA

Andy, in addition to the motor configuration High/Low, mid/low and low/low, you also have axle length, available in two different sizes, 48mm and 58mm, and then there's the pattern of holes for mounting. You can usually start by dividing tanks into two groups, long shaft (58mm) and short shaft (48mm). 58mm shafts fit tanks like the King tiger, Panther and Jagdpanther and both the M41 and M26. The short shaft GBs fit tanks like the Tiger One, the Sherman, the PzIII and IV, and anything that runs with the same lower hull, like the PzIII and the Stug III.

Then there's the hole pattern on the bottom of the gearboxes, but holes are easily added if you need to. So while you can swap gearboxes from a panther to a king tiger, you can't put those gearboxes into a Tiger One. The Tiger one boxes will fit a Sherman, but not a Bulldog.

Hope that helps.