mounting Fisher Price transmissions
 

We may be using Fisher Price motor transmissions for one of our tasks, namely setting a ball shooter.

Has anyone had experience in mounting these transmissions? They don't seem to have any good mounting lugs or mounting holes.

If we modify the transmissions by drilling mounting holes, is that a violation of the rules about modifying motors?

Any experience about this will be of great interest to us.

Jim Wick
sorry, too old, too ugly for a photo

Re: mounting Fisher Price transmissions
 

These two pictures show how we mounted the transmission in 2008. Don't mind the messy wiring -- we cleaned it up later :D

http://picasaweb.google.com/quixilve...49444474043890

http://picasaweb.google.com/quixilve...49461653913090

EDIT: Besides the one screw holding the transmissions on, there is also two clamps, kind of like how parts are clamped to milling machines.

Re: mounting Fisher Price transmissions
 

We mount the fisher price transmissions which control our arms in a similar fashion.

The shaft they turn keeps them in place, locked up against the square tubing (in our case, 1.5"x1"). Shaft collars keep the transmissions from sliding out (off the shaft).

To turn the shaft (1/8" keyway shaft), we machine an octagon hub/block that picks up the octagon shape of the inside of the fisher price output. The hub is then bored to the shaft diameter and an 1/8" keyway is broached.

Hose clamps are used to hold the white plastic output of the fisher price transmission to the octagon hub to avoid slippage.

Re: mounting Fisher Price transmissions
 

Isn't that output piece a octagon?

Re: mounting Fisher Price transmissions
 

It is an octagon.

Re: mounting Fisher Price transmissions
 

And if we don't have a vertical member that will work in the right place, it's pretty easy to turn some plate aluminum of reasonable thickness and some angle aluminum into a pair of mounting brackets.

1) Cut the plate to shape. You'll probably want some form of triangle. Note: Helps to have at least one side exactly the same.
2) Locate and drill a hole for the axle. Try to get it in the same place on both plates.
3) Attach the angle aluminum to the plates.
4) If more weight is needed elsewhere, leave about 1/2 inch all around the edge of the plates and the holes in them. Remove excess material inside that as needed.

We did that in 2004 for a winch system similar to the one Eugene posted. Started using handy vertical frame members in 2005, when they weren't moving relative to the base of the robot.

Re: mounting Fisher Price transmissions
 

You can modify the gearbox any way you want. You cannot modify the actual motor.

I'm thinking about removing the gears and mounting them between two plates (like an AndyMark Toughbox).

Re: mounting Fisher Price transmissions
 

We do that every once in a while and it works pretty well for us, especially when we want to cut out the final stage and output from the second-to-last gear. If you use an open plate design, be ready for a really loud, whiny gearbox.

Re: mounting Fisher Price transmissions
 

Thanks everyone for replying to my original post. The information is very helpful. I'm always amazed and pleased at the good will among the FIRST teams.

Jim Wick