Mounting Fisher Price Gearboxes

Anyone have any good sollutions for mounting the white plastic gearboxes that come in the KOP

I am wiery of just drilling into it.


  • Bochek

before last year We would always file one side down to make a flat, then open the gearbox and install screws from the inside out.

If you are looking for an easier mounting solution maybe you should look at their 36mm gearboxes will accept the FP motor.

FP welds a bar onto a nonrotating shaft than runs through the output gear hole. This provides a shelf for the gearbox to rest on and prevents rotation.

In the past we have wanted the shaft to rotate so we rested the gearbox on a piece of aluminum angle, 2x2 x 1/4 thk, and transfered the hole from the gearbox. The hole will end up against the web of the angle. we then used clamp collars on both ends to prevent axial shift.

You will have to adapt this for your application.

In the past we have mounted the FP gearboxes using the flat surface on the rear of the gearbox and then pass a bolt through the center hole. Last year we used the gearbox to run the o-ring drive on our ball launcher. In fact, we mounted the gearbox to a 2x4 wood stud and used a lag screw to hold the gearbox in place and then lagged the 2x4 stud to our frame. It made a hard mounting situation pretty easy actually.

Good Luck

Years ago, when the drill motors/transmissions still came with the actual plastic drill casing, we used expanding polyurethane construction adhesive as a bedding compound to form a flat base on the curved case. We put waxed paper on a flat surface, rigidly held the case in the proper orientation, then squirted the glue in the gap at the base, followed by a couple of wedges of scrap wood. Once cured, we held the whole assembly down with large hose clamps. We used PL Premium, which is available at Lowes I think. They have many types, but this particular one will stick to a lot of different materials, including metal. It costs about $3.50 a tube.

If you use this stuff, do not get any on your hands or clothing!

We made a custom aluminum plate that bolts up to the FP gearbox. Then we put a 90 degree bend onto the bottom part and mount it to the robot, to mount them vertically. I’ll post pics later tonight.

We make an aluminum adapter with radial screws that mates to the moving plastic wheel with the slots. We then pin the adapter to what ever shaft we are using. On the other side of the gear box we have a roughly triangular plate that goes over the three screws that hold the gearbox together. We remove the screws and drill through the plastic and use these three holes to mount the gearbox to the frame or arm or what ever.

this year we’re using 5/8" pvc material attached straight to the gearbox with bolts going thorugh the holes you see on the gearbox that hold it together. (i’m recalling this discussion we had from memory just now) then, we used aluminum angle to mount the gearbox perpendicular to a surface. relatively simple. so that’s how we did/are doing it.

If you take a triangular plate or something similar, as long as it has at least one straight side as long as that “shelf” on the opposite side and end from the motor, then put a properly placed hole through where the output shaft would go, you should be fine. We’ve done that for years without a problem. If we have a mast, though, we’ve just used that.