A Transfer Case with no Gearbox??
 

Hi,

I'm building a custom frame/chassis but can't find smallest gearbox because the frame is very tight. If anyone knows, what is the smallest gearbox?

Or, maybe does the transfer case will have enough torque if running straight from motor (without gearbox)? With custom driveshaft of course..

Let me know your thoughts..

Thanks"thumbsup"

Re: A Transfer Case with no Gearbox??
 

I just have a question on how you will be running the motor to the driveshaft? Do you have a custom spur to go from the driveshaft to the motor pinion gear?

Re: A Transfer Case with no Gearbox??
 

no spur and pinion, but I have made a adapter from 3.175mm motor shaft to 5mm on driveshaft.

Re: A Transfer Case with no Gearbox??
 

Ah nice. I actually wanted to do something like this for a build that I have already completed but also thought of the motor to driveshaft ratio wouldn't be crawler friendly? Am I thinking that right due to no spur?

Re: A Transfer Case with no Gearbox??
 

we realy need more information if you want help and pictures with out pics it dident happen

they sell planitary gear boxes that bolt directly to the motor they come in differnt ratios and there the same size around as the motor and about half as long thats the most compact gru your gona find it might be enuff gear reduction to go straight in to the tcase depending on what kind of gear reduction is in the tcase

i do have 1 rig that the motor goes directly to the transmission/tcase with no gru and no pinnion and spur but the rig is vary light and runs tiny 1.0 tires and is powered by a big outrunner that gives me goobs of torque so gear reduction isent a real issue but a heavyer rig with bigger tires will not be fun to drive

Re: A Transfer Case with no Gearbox??
 

As a general rule, a 7-12:1 reduction is needed to go from motor to the axles. However you can get away with less or more depending on axle size and truck usage. Most spur to pinion ratios are that 4-7:1 reduction and most gear boxes ala Axial offer a further 2.46:1 reduction.

Re: A Transfer Case with no Gearbox??
 

here is what I build....
https://imagizer.imageshack.com/v2/6...922/zivls5.jpg

Transfer case will be right under the seat. In picture I have installed the motor directly to the chassis.

Re: A Transfer Case with no Gearbox??
 

You might be able to sneak a Creeper T in there somewhere. It has 30% overdrive, though (less than 2:1 gear reduction up front, and 2.6:1 rear). The RC4WD atlas ii case is only 1.5:1. Are portal axles an option? You need more gearing.

Re: A Transfer Case with no Gearbox??
 

Axle is RC4WD's K44. Portal axle is ok probably, I have 1 set. But I'm using K44 just because the ground clearance, wanted to be as low as possible and I actually like the look of straight axles.
That Creeper T is awesome but the height maybe not available in the chassis. I have 27mm high transfer case and that still thick. 25mm thick what I'm looking for.

Re: A Transfer Case with no Gearbox??
 

You need a few mm clearance, maybe mill your current transfer case down on both the top and bottom of it?

Re: A Transfer Case with no Gearbox??
 

so heres what i would do if it were me i would pick up a low kv brushless stubby 540 motor and a 5:1 planitary box in to a tcase then to portal axles your gearing will still be high though
in my opinion you need to do more work to the chassie to get everything you need in it on it
it looks great but ya kinda shot your self in the foot
it would make a great bouncer if thats were ya want to go with it


heres a link to a gear reduction unit
https://www.ebay.com/itm/US-1-5-Plan...-127632-2357-0

Re: A Transfer Case with no Gearbox??
 

another option is to make your own gearbox there not that hard to make you just need the gears and some shafts maybe gut a 3 gear or something the open gears dont seem to pick up alot of debrie so you can run them open if you use metal gears you can get away with out grease and the rig will sound like some kind of mechinery

Re: A Transfer Case with no Gearbox??
 

...another option is to get a low kv brushless motor and a AM32 esc for smooth low gearing and without noise. "thumbsup" T-motor has excellent motors With 900kv for example
https://store.tmotor.com/goods.php?id=791

Re: A Transfer Case with no Gearbox??
 

only way to get direct power to work at all is if you use losi worm gear axles.

Re: A Transfer Case with no Gearbox??
 

Just an update, I ended up using planetary gearbox.

https://imagizer.imageshack.com/v2/xq90/923/2rW9us.jpg

Well it came up a bit smaller, driver cramp a bit:)

Re: A Transfer Case with no Gearbox??
 

in my opinion you need to streach that chassie just a hair its so tight as it is lol