Sidegrades for EXPLORER-MK1 3D PRINTED 1:10 RC CHASSIS

Changelog:

2025-02-23:

• Updated Steering bearing section
  • Linked to a remix that doesn't require reprinting the front chassis

2024-12-20:

• Added STEP files for both motor mount versions as requested
• Added REAR-SET_FRAME-3650-OG-HOLES as requested
  • This version includes the original motor mount holes
  • This file is untested

GOPRO MOUNT:

Both rear shock tower options modified for mounting a GoPro camera. If you use an M5 lock nut you might need a longer screw than the standard GoPro pin has.

MOTOR MOUNT: 

Added mounting options for 3650/3660 motors to the car. The mount requires six M3 lock nuts and six M3x14mm countersunk screws(I used 16mm in the pictures). The motor is held with M3x10mm countersunk screws. Since the 3650 motors have a 3.175mm shaft I designed a replacement for HSP 08065 with less tolerance to reduce back and forth movement of the input gear. The replacement requires two M4x4mm grub screws. 3660 motors come with a 5mm shaft but I still added a HSP 08065 replacement for those. HSP 08065 with a 3650 motor might still work with these, but I didn't test it ‘cause the replacements I made haven’t worn out and are still intact. 

Notes: 

• The only part that is different between 3650 and 3660 is the rear plate.
• The motor mount has a offset variant that moves the screw holes by 30°.
• If you have a high kv motor the gearbox bearings should be able to handle higher rpm. I tested with random leftover bearings at first. Using 3900kv motor and a 3S lipo the bearings got way too hot, you could smell that the PLA was melting. I switched those out for ABEC-9 ZZ-Bearings.
• My worst 3650 motor can handle the gear ratio, but only on 3S. On 2S it cogged so badly that the ESC had enough pretty quickly. So I recommend going 3S or sensored when using a 3650. The 3660s I tested had no issues.
• The dimensions of 540/550 motors are slightly different. You should be able to use the 3660 rear plate for those or just comment with the dimensions you need and I'll modify the rear plate.

STEERING BEARING:

Added a bearing into the front plate to reduce flop, ‘cause the original steering arm is supposed to sit in there loose. There are two variants, one that uses a 7x11x3 bearing and another that uses a 10x15x4 bearing, which is already used in several other places on the car. Put a M4 washer between the steering arm and the steering arm support. I added a picture of a testprint, to show the 10x15x4 variant.

There is a remix by Valmadiaz that doesn't require reprinting the whole front chassis. If you have already printed the chassis and want to use a bearing for the steering I recommend using his design. Link: https://www.printables.com/model/1204161-improved-steering-arm-for-explorer-mk1

My servo horn was hitting the steering arm support so I added a shorter version that only uses the two front holes. I dremeled the tip of the servo horn before realizing I could just shorten this part... But hey, let's not delve too deeply into that, shall we?

MOTOR WIRE HOLDER:

Added motor cable routing holes to the upper gearbox part. 

PRINT SETTINGS:

For print settings check the original print guide.

MISC:

I also made a center differential for the car that can be found here. I still want to replace the whole steering system with a all-bearing-design using 3x7x3, but I know nothing about steering systems so this requires a lot more try.fail.repeat than I thought.

"Happy printing, and God bless, my friend."
— Bob Ross