3D printed belt sander

Photo of the V1

V1

This initial version was certainly "throwing stuff at the wall to see what sticks" in nature. i just wanted to model up some stuff, print it and watch what broke.

one issue you can pick up from the photo and certainly from demo videos, is that there is a lot of issues with the belt oscillation there are several factors things that are causing this to happen such as:

- Inconsistent thread on the motor leading to a nut at a slight angle that is amplified over the connecter

- The motor lying on only 2 anchor point and leaning slight over the base at a upward angle

- the ball bearing side being unweighted and therefore vibrating due to rotating and "pulling" forces from the belt

-having the belt slip off and shift around many times during demos

wireframe of the new connection system

New Motor Connector System

after figuring out that the motor's thread had a certain shape, i realized that i would utilize this to both improve the installation process and also remove the use of a nut therefore reducing the oscillation issues from the v1 due to inconsistent threading. I quickly modeled and printed this test piece (shown to the left) and was overjoyed to found that it worked!

photo of V2

V2

Overall this new connection system had a HUGE EFFECT on the issues with belt oscillation, another improvement with this version was small "railings" for the belt to make sure it doesn't slip off during usage.

Some problems still to be solved is the issues with not weighting down the ball bearing side to reduce it's flexing and vibration, and the fact that the joint along the bearing keeps shifting out of the bearing over long periods, eventually falling out.

V3 (cooling system)

V3 adds a full cooling system, the reason for this is that after doing several long term stress tests on the motor and setup of V2 i figured out that the motor heats up rapidly. This issue is to the point where it both risks damaging itself and damaging the user through burns. The cooling system is very simple with just a fan blade. The fan blade is turned using the existing rotational force generated by the motor onto the connection system. This is allowed by two 90 degree gears alongside bolts and threads. this "version" took longer than both past versions due to the further complexes with tens of tests prints. This was in order to make sure that the gears were alighted and ensure the grinder lasts.

Right is initial part then moves counter clockwise till final part, bottom

V4
(belt sizing and final adjustments)

the sanding belt i am using is ~18.8mm in width that means the areas where the belt rotates must have the same size gear pieces and TPU belt in order to create a proper sander. This done by lining up the belt area of the two areas and then adjusting the overall length based on the ratio between overall length and the gear area length. then removing the "extra" length of both parts. In regards to the length of the belt we can just do a circumference calculation, cut it to size and lightly glue the ends.

V4

finished up testing on the cooling system and then moved on to printing what i hope to be the final parts required, such as printing the base with a extended height and high fill density to ensure strength. During testing this seems to work awesome after press fitting the motor using a simple clamp.

3D printed belt sander

This project is a follow up to the TPU BELT in attempt to adapt that system for a homemade belt sander