Tracked Tarmo

Work In Progress (Edit 14Jul'23 - less WIP now - more Test the Current Iteration)

***Important notes at the bottom***

I want a tracked vehicle. No idea why, but I still want it; I also have a budget, so I want to use the parts that I have on hand and seem to work - Tarmo5 parts!

That said, I did look to see of there was something I liked out on the interwebs…

I looked at the Fast Rc Tank by #Froy192, and while I love the design, I didn't want to shell out the $200CDN for the gearsets and motors.

That track design though… Hmmm…..

A chassis. I noted the mirrored 4WD body by #Willy. With the 1 motor end from his WIP chopped up and swapped around to allow 1 motor to drive each track and keep the weight balanced L to R, then lengthened to accept a 5200mah 3s pack… Hmmm again….

Sadly, I recently gave up on my Tarmo4 (more shredded gearboxes than I care to count), so I now have a full ESC and motor set, along with the spares I always like to keep on hand.

So all that in conjunction with my desire for tracked goodness and………..

TRACKED TARMO!!

This might work.

(Edit 14Jul'23)

This is working! With the PETG drive wheels it seems to drive well. I haven't broken anything yet, though the track has distorted a bit. The crimps are a bear to get right! It sucks back power - good packs are a must and keep the remote set low! I still haven't increased my power past 30% - it's still pretty quick for my tiny back yard.

BOM Printed:

Print off the plates in the material specified (PA is voluntary for those with enclosures and daring… PLA+ seems to work so far for me where the PA parts failed to print). You'll need 2 track and wheel plates.

If you chose to print the parts individually, print in the number specified in the part name.

BOM NON Printed:

2x 6x 8mm hub – each set in the link has 4 amazon

4x 4.2mm ID x 8mm OD x 4mm standoff I used 2 only - you can also use 8mm standoffs if available - 1 per hub used to center the #4 bolt.

2x 3542 Turnigy brushless outrunner motors (same as Tarmo4 and Tarmo5)

2x Brushless ESC (I'm using 2 10BL120 Quickrun ESCs - spendy, but they work…)

Radio and receiver capable of TRACKED VEHICLE operation. I am using a Radiolink RC6GS that works more or less… YMMV and if you have a better (affordable!) option, let us know somehow.

38x48x138mm Lipo pack or smaller to fit the chassis. I'm using a 5200mAh RoaringTop pack - so far (edit 20June2023) not so good…. Use a much higher C value - maybe 100c - my 50c packs can't keep the volts up when drawn down by both ESCs. (end edit)

HSP 08065 Tarmo4 hex motor adaptor x2 (1 purchased set usually has 4)

1/16" wire rope and crimps - amazon

15x24x5 bearing x12 - the large Tarmo bearings

***BOLT LENGTHS ARE NOT ASSURED!***

***I HAVEN'T MEASURED AGAIN AFTER THE PROTOTYPE BUILD!***

***CUT BOLTS DOWN AS REQUIRED AND TIGHTEN WITH CARE!!***

M4x30 hex head bolts x2 I cut mine down to size for the idler wheels.

M4 locknuts x2 for the idler wheels

M4x~32 Allen head bolts x2 for the drive wheels - cut to fit based on washers needed to secure the wheels to the axles. The relief behind the embedded nut inside “2x Drive_WheelSide_v2” is minimal to keep the part strength up, so don't tighten until the bolt has been measured and cut to length or the part will break.

M4 nuts x2 embedded in the drive side axle “2x Drive_WheelSide_v2”

M4x35 Allen head bolts x4 for the gearbox lid

M4x40 Allen head bolts x4 for the motor mount to gearboxes

M4x16 Allen head bolts x2 for the battery securing tabs.

M4x20 Allen head bolts x8 to secure the 2 bumpers to the gearbox covers.

M3x20 countersunk screws x8 to secure the hubs to the drive wheels.

M3 lock nuts x8 and washers x16 to secure the hubs to the drive wheels.

M3x12 Allen head or other x6 for the motor to motor mounts