Walthers Rotary Dumper Modification

The modification of a Walthers Rotary Dumper to handle two bay to quad hopper cars.

NOTE:Click on picture to enlarge. Click back button on your browser to return to this page.

The first part of the solution was to glue a 1/8" "H" channel to the bottom of the gripper. Make sure it's short enough and glued right at the edge of the gripper so it won't interfere with the back part of the gripper.

Here's a little item that helps hold the grippers extended to their highest position to facilitate the gluing of the small "H" channels to the bottom of the grippers. It's called an alligator clip. They can be bought at any store selling electrical products.

Here's a better view of the "H" channel glued to the gripper. I made them about 5/16" long and glued them close to the front of the gripper so it will clear the back side.

With the dumper in the load/unload car position you can see how much the grippers need to come down to hold the car.

I measured the distance from the top of the hopper to the bottom of the gripper. It was about 3/4". So next I had to shorten them up.

Here the rotary drum is sitting on two v-blocks. You can see that the grippers are just barely touching the top of the hopper. The solution is to cut off the cam riders, shorten the stem and re-glue the cam rider. The next several pictures will show the procedure.

I used a set of side cutters to cut off the cam riders. If you build this kit to be able to use plain hopper cars then this should be done before complete assembly of the rotary drum.

The red lines on the diagram show where to cut the bottom of the gripper shaft. File flat and file the cam rider flat then glue on the bottom.

Again I used the alligator clip to hold the spring, remember to put the spring on before gluing, up while the cam follower was glued to the bottom of the gripper shaft. I use blocking to hold the cam rider up against the gripper shaft until the glued joint dried. This is the way to do all 8 gripper shafts.

To finish off the holding grippers I glued on an "T" beam made from a piece of .060" thick by .109" wide on a piece of 2" X 12" HO scale styrene. This was glued to the bottom of the "H" channel.