Motor Mount and Wheel Kit #27972 Disassembly Help
LarryCardo
Posts: 28
I purchased the #27971 motor kit, because I found I was spending too much time designing robot platform motors. I ran into a couple of issues.
Instructions call for caution installing the bearings. After many tries, I placed the bearings in the freezer and heated the bearing housing to 200 degrees in the oven. The bearings then dropped in the housing.
The installation of the roll pin into the axle was more difficult. Instructions say to use a "small" hammer and tap the roll pin into the shaft. I had to use a BIG hammer, and it took about 30 hard blows of the hammer to install the roll pin. I now find myself in a position to remove the roll pin--and I have no idea how, because of the significant force used to insert it. Any suggestions?
The wheel went on the axle and was tightened by the wheel screw. Now I can't remove the wheels from the axle? Any suggestions?
I love the Parallax electronic products, but now question the mechanical tolerances.
Larry Cardo
Mentor, OH
Instructions call for caution installing the bearings. After many tries, I placed the bearings in the freezer and heated the bearing housing to 200 degrees in the oven. The bearings then dropped in the housing.
The installation of the roll pin into the axle was more difficult. Instructions say to use a "small" hammer and tap the roll pin into the shaft. I had to use a BIG hammer, and it took about 30 hard blows of the hammer to install the roll pin. I now find myself in a position to remove the roll pin--and I have no idea how, because of the significant force used to insert it. Any suggestions?
The wheel went on the axle and was tightened by the wheel screw. Now I can't remove the wheels from the axle? Any suggestions?
I love the Parallax electronic products, but now question the mechanical tolerances.
Larry Cardo
Mentor, OH
Comments
Can you post some close-up pictures of your set up?
Dave
Could you call 888-512-1024 and ask for me? I'm familiar with what you're experiencing I think. Let's get you fixed up!
-Matt
That being said, I think your solution to getting the bearing to seat, was a great idea. We do want that to be a snug fit (so that the outer bearing ring doesn't rotate in the pocket) - and heating/cooling of the parts seemed to work well.
And the roll pin issue: They should be very snug, but not too snug that you can't get them back out if you need too (otherwise you may damage the axles). A good set of "pin punches" (as we talked about) can be a life saver, if removal is necessary.
The Axles are drilled at .125" to accommodate a .125 roll pin. If you wish to have an easier time getting the pins in, this can be reamed with a #30 drill bit (.128") - any bigger may result in the pin being too loose.
Let me know if the replacement parts are satisfactory ;-)
Thanks!
Matt
You solved all my issues. Parallax should be proud to have you as an employee!!!!!!!!!!!!!!!
Larry Cardo
Mentor, OH