[FTC]: Tetrix V2 motor internals

Hi All,

I took apart a new motor and here are some photos of the internals. Can someone take a look at the brushes and comment? The motor was still running but they appear to be installed incorrectly. The curvature on the contact surface of the brushes is rotated 90° wrt the curvature on the commutator and that seems rather odd. Increased wear can be seen on the commutator.









Did you take it apart because it failed? If so, how? I am a little wary of switching to the new motors because we understand the limitations of the old motor very well. I would appreciate your insights.

I took it apart because the gear box failed (after < than 30s of light use–was likely a defective gear rather than a design deficiency) . The actual motor was fine but we’ve been chasing gremlins in our robot and I wanted to see if there were any surprises inside. Other than the brushes, all seemed good.

That odd rotation on the brushes has been around for a while. I noticed it several years back on our first motor that failed, and I thought the same thing as you.

I’ve never heard any other comment on it. I just assumed this was one case where logic didn’t match actual application.

Looks like some more research is required.

Phil.

Hi Guys,
I have looked into your question and just wanted to follow up in regards to the brushes of the new V2 motor. The Carbon brushes are installed correctly. The new revised motors now have arch brushes. The arc offers a release for electrical sparks. If the brushes are turned 90 degrees, they will still function. However, over time the arc brushes will function more effectively than the flat brushes.
I hope this clears up some of the concerns.

Regards,
Tony Allen

Rookie team checking in:

We had some issues early in the year with failed gearboxes on the old motors. When we disassembled them we found a plastic gear that was stripping out.

We were excited to use the new motors because they are stronger. When one failed we took it apart and found that all the gears are metal. The failure on the new motor was due to one of the gear shafts popping out of alignment. We were able to fix the gear box and use the motor.

Overall our opinion of the new motors is very good when compared with the old motor. We have found them to be SIGNIFICANTLY more powerful and with an improved gearbox.