Laser motor mounts are wrong!

Robotics and electronics discussion Mechanical design and actuators
1

I recently ordered 2 of your Laser cut brackets for my GM9 motors that I ordered from solarbotics a while back. Well I just get around to putting the brackets on and they aren’t going to work. First off, The motor spins in the bracket when mounted (not completely secure). When I put them on backwards (with the bracket on the double flat axle side) it is impossible to mount anything on it, the bracket gets in the way. Also the holes are too small for 4-40 bolts. Another thing is that the bracket is too short to mount it flat on a surface. Could I get a refund?

2

Hello,

I’m sorry to hear the motor mounts aren’t working for you. If you have a problem with the design, you might want to contact Solarbotics about it since they are the manufacturer of the part. However, I just looked at a unit, and it looks okay to me. A 4-40 screw fit through the hole that is against the motor. The holes that are against the surface you are mounting to are smaller, but can’t you use a smaller screw or use a drill to make it a bit bigger? The bracket being a little short should let you tighten the whole thing more. I’m not sure what you mean about the motor spinning, but the bracket is made for a surface that extends over the gearbox, so I don’t see how it would spin. Perhaps you can post a picture of your setup.

- Jan

3

I bent the bracket so now both of them lie flat. The reason it spins is when you mount it on the single flat side (or as the current design the completely flat side) the screw no matter what type, how long, etc would make the motor spin without the “nub” holding it in place. But when you mount it on the side with the nub it makes the motor useless, as the bracket gets in the way of the wheel, etc.

4

If you mount to a surface that extends over the gearbox, it gets sandwiched between that surface and one end of the bracket, which should prevent spinning. Is that not the case?

- Jan

5

That was what I was trying to say. I was unable to have it “sandwiched” between the base and the bracket, thus it would spin. I have revised the body and now it works fine.

6

Great!

- Jan

7

Ironically, my lexan base was wrong, and the entire project was canceled. I am instead using a Pololu Laser cut Round robot chassis (which is perfect :D), A ball caster and the tamiya 70097 gearbox. it is working perfectly and I can take my previous project and put it on this. Thanks Pololu!