DirtyBird69

Found this t-55 online and I really like how this guy set up is drive train...anybody know what it is?? I like how clean it is and how much space it saves..

Panther G

Those are gear motors. It is a good way of propelling a tank as long as you can calculate the maximum RPM you would need because that is how these are made by RPM of the gear reduction at the pinion gear.Or end of the sprocket shaft. Then you need to fix the sprocket to the reduction output shaft.

DirtyBird69

seems like a very efficient set-up...why don't more people run them? I'm seriously considering trying it on my next project...

yellowshaker

My Feedback: (1)

I think there was a thread on this a while ago. Seems the durability of these drives is in question....or at least it was at the time. Still, might be worth a try on a light tank.

Perry S.

The correct gearhead motor needs to be selected as Panther G pointed out. The link he provided shows rpm and I believe that is probably an unloaded speed. Didn't do a deep dive into the site but what you really need is a torque speed curve. Torque is what you are after ad for a given motor size you can only fit so many gears into so much space.
Not saying youshouldn't investigate further but these things have been around for years and years and if it were that easy I imagine Tamy or HL or whoever would just put these in instead of making all the space for their own custom gearbox designs.

Perry

DirtyBird69

would be ineteresting to see what's all in there? (plastic/metal/what?). My German is a bit rough , but from what I cansurmize in his threadhe used PGM-37 motors that rotate at about 170 RPM's. he's used them on other tanks with no problem. he did say speed is a bit limited but the motors are rated for up to 12v so a bigger battery could always betried(he thought an 8.4v would be perfect).I found some, but not sure if there's anything comparablehere in the US. There appear to be 3 different versions with different gear ratios, I can't figure out which one would be the best ratio to use on a 1/16 tank..I'm thinking "1:30" ......

http://translate.googleusercontent.c...XedVGDq0cK-xng

dyeager535

My Feedback: (1)

No idea WHICH Tamiya gear box was in question, but I saw a post elsewhere that said the stock Tamiya gearbox was "only" a 60:1 reduction.

With reduced reduction, the motors will draw more, especially worse getting the thing started. Then add in the increased top speed.

DirtyBird69

well they do offer the PGM-37 in a 1:70. like I said they offer 3 different reductions, and I have no clue as to which one would be best suited for our tanks.... Definatley gonna give these a try..he'll their cheap enough and if I can eliminategearboxes all together, I'll have thatmuch more room for a bigger speaker...

Panther G

They are certainly worth a little experimentation. Those ratings in the page i posted are at the gear down shaft with no load. 

Panther G

The gear drives at Servo city go from 138 oz/in.@ 12 v all the way up to 1,100oz/in. So I'm sure there is plenty of torque available with these. 

mizuinu

For the first gen Leopard/Gepard.

http://www.jt-scale-militaermodellba...tte-p-708.html

If I get my tax refund........

danlrc

From a post on measurements made about a year ago on my Tamiya Tiger 1...I think I fixed the test voltage at 6V.

"I got my hands on a tachometer and measured motor speed and drive wheel RPM. Motor speed was fixed and averaged about 2000RPM (varied about 1900 -2100) and drive wheel was 20.5 RPM. Total gear reduction then is about 98:1.
The gearbox is a Tamiya with a Schumo "3x geardown" unit on it. Standard Tamiya motor."

The small size of the gearmotor gearhousings indicates small gears. Could they really handle the same loads of the much larger gears in the current gearboxes? Better materials maybe?
Good things besides their compact size is that they are very quiet and are sealed (no lube or dirt issues?)

lposter

Those are planetary gears on the inside. So the giggest one would be the size of the box itself. Seems to me thats way bigger than the largest one on any standard 1/16 gearbox.

If they are made of metal...Im not sure the size would have much to say?

p

heavyaslead

Looks like a planetary gear system.

Difference is the drive shaft will be center line rather than offset in a planetary system.

The main disadvantage of palnetary (for tanks) is a relatively low gear ratio, maybe 3:1 to 6:1 depending on how many stages (adds in length).

For the one pictured, looks like it could not habe more than 2 stages in the can.

The T55 has a higher top speed than WWII tanks so the ratio might be OK for this application.

Can't beat the sealed gearbox option, a great solution for an already space cramped model!

The standard T55 Hooden motors has near 32 mph scale speed with plastic tracks.

Tanque

Like everyone noted those are gear motors. There are many brands. Ones that come to mind are Pittmann ( most common in the US), eScap and Maxxon.

Pittman versions that I've opened used zinc alloy gears, bronze bearings. Usually fairly robust. Don't believe they'd wear out that quickly.

There are more and more coming out of China, some are superb quality, some well, aren't.

Higher end types, Maxxon, eScap use better grade materials, gears and ball bearings but a single unit can cost many times more than
the lower types.

I've used them for years as turret drives, elevation motors and the like. I happened to be able to scrounge quite a few years ago so I got mine
for little money. With the current crop of readily available gearboxes for tanks I don't see many reasons to use these unless you have or find a
supply of suitable cheap units that beat the cost of a regular gearbox by a wide margin. Being sealed against dirt and somewhat quieter aren't enough reasons IMHO. The work to modify the output shaft in most cases and the tank itself to use one of these is just extra work. If they do break or
wear out you stand little chance of being ale to fix them. The motor end is sometimes available separately from the gearhead but finding them
is difficult; usually only from a specialty supplier from whom you will pay a first cabin price.

Unless you just want to be different I'd use a standard gearbox.

Jerry

DirtyBird69

well I'm looking at them from a space-saving standpoint....sick to death of trying out how to figure out how to cram everything in there lol. I'm big on sound quality/volume, so this would a lot more options as far as speaker size/placement,etc....