Losing our wheels

We are having a problem with the wheels falling off. This occurs when the wheels are attached directly to a shaft coming out of the motor clutch assembly. There does not appear to be any way to lock the shaft into the clutch assembly.

In searching on some of the VEX forums, others have had the same problem. One team fixed the situation by installing a second side rail so the wheels were trapped between the two pieces of the frame.

Has anyone come up with a different solution?

I dont think there are many other options…
I just use shaft collars one inside the side rail and one on the outside of the wheel. It works 100% of the time but is not very convenient sometimes.

When i frst had this problem my clutches where breaking so i just put a lock collar in place of them and it works fine.

                      THIS IS PROBOBLY NOT FVC LEAGAL!!!!!

i always use a side rail, especialy on tank tread

I already sent this in an email, but I will post it as well, for the benefit of everyone else having this issue:

[FONT=Arial][FONT=Arial]In the situation you described adding a 2nd side-rail is our recommended solution. [/FONT][/FONT]
[FONT=Arial][FONT=Arial]I would go as far as saying that every Vex shaft should be double-supported in some way. (Running through 2 bearings, or coming out of a motor and running through 1 bearing.) This may be cumbersome in some applications, but should be easily implemented in most designs.[/FONT][/FONT]

[FONT=Arial][FONT=Arial]At the current time there are no plans to design a clutch with an integrated shaft retainer. We believe that the current system of using shaft collars for retention is adequate.[/FONT][/FONT]

[FONT=Arial][FONT=Arial]In most applications it is perfectly fine to direct-drive the wheels. (In instances of excessive load, the clutches may pop so the system would require a geared speed reduction to reduce the load on the motor). Again, we recommend double-supporting ALL shafts. If you wish to direct drive a wheel without a second side rail and still retain it, you can do so by removing the motor clutch and installing a shaft collar in this location (in between the motor and the plate the motor is mounted to.)[/FONT][/FONT]

If you are willing to risk a motor you can remove the clutch(es) and just sick the axel that the wheel (or gear) is on directly in the motor.

I dont understand what will break the motor and i dont really what to test mine to find out. But if the motor is forced in a direction when it is not on will it break it or does the motor have to be on? Has anyone broke a motor other than dumping it in water? How?

i’m pretty sure it’s FVC legal, but you’ll kill your motors that way

If you do not use a clutch you risk stripping the gears on the inside of the Vex motor. These gears are the same ones as those tiny black and white [replacement] gears in that small bag in the Starter Kit.

ok i can replace those

If I only have one piece of metal to fasten wheels to, I use spacers. There are 6/32 bolts that are long enough to bolt a motor and the large spacers to the metal frame. This leaves enough room to place a locking collar between the clutch and metal frame (and retains the shaft very well.) The bearing block uses the two extra holes on the other side of the metal rail so I can use 8/32 hardware to fasten it into place.

I have found some longer 6/32 bolts at Home Depot which allow me to place lock washers on the mounting hardware to keep the bolts tight. I have even used 6/32 bolts sufficiently long (1" I think) to mount large spacers and a bearing block between the motor mounts and the metal frame. (There is still room for a locking collar between the clutch and bearing block.) I don’t know if bolts from Home Depot are FVC legal.



You can just use threaded beams which are alot stronger

really man I just read this post and laughed. No offense,but I can’t believe someone doesn’t have the common sense to have the motor, the axel out of it, metal, berings on both sides, a washer or spacer, the wheel, then another washer and a collar lock. Hey man, I’m just try’n to be helpful.

Hey dude, chill. That wasn’t helpful, that was rude. Whoever asked this problem did not know that… we were all noobs at one point in time. So just… chill.

One trick that I use is to ‘rough up’ the end of the metal shaft so that it sticks in the clutch better. You easily can do this by repetedly tightening shaft collers on the end of the shaft to make little indentations. It’s always better to use a lock coller on the shaft, but if you have no room, then this method can work for the right applications.

Ya if you buy the whole sale axels or the 2 foot pieces if you cut them with wire cutters into the sections you want it kinda makes barbs on the shaft the is brutal if you get scraped with it but sticks into the clutch very well and usually the clutch will come out of the motor before the axel will come out of the clutch

Yes, we are new to VEX. Thanks for all your help. We will try the suggestions.

I have noticed that none of my motors can actually hold an axle. The only way I’ve found to hold an axle is to provide some sort of mechanical block on the other end of the axle creating a wheel/gear/sprocket sandwich.
Is there anything I can do that is not permanent? ?(i.e. glue the axle on)

If you use wire cutters or the collars and make indentations into the axles they tend to grip better. With the collars just screw them really tight on the end and they will push in to the axle and provide little barbs that grip into the plastic. i am curious if anybody else has any other way of doing it.

This is permanent, but it would work pretty well. Glue a collar on the motor’s clutch. Then you can tighten the collar to keep the thing on. The glue (or tape) would have to be pretty strong.