Walthers Rotary Dumper Modification

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

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Completed Rotary Dumper

When I installed the dumper into the pit I got a surprise. The bottom part of the grippers that ride on the cams in the pit didn't line up with cams. What happened? Well when I put the floor in I didn't look at the drawing on proper orientation of the floor and I got it in backwards. Luckily I hadn't glued down the cams yet. So now I needed to come up with a fix. The next couple of pictures will show what I did to fix that plus how I modified it to work with two bay to quad standard hoppers.

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Here's what it looks like done wrong. The whole floor should be flipped over to make it correct.

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Here's another look at it without the cams. The shorter two slots on the left should be on the right in relation to the gear shaft.

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Here's the fix. I measured the distance between the two walls, approximately 7".

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Then I cut two lengths of .125" square styrene and glued them down to help align the cams.

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Next I measured from the edge of the slot to the wall. Then I cut a piece of styrene that distance and glued it down on the opposite wall.

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Here you can see the small piece of styrene, by the way I used the left over pieces that came from making the pit shorter. I'm gluing in the first cam useing a 1-2-3 block to keep it square. The bottom tab's of the cam that fits into the open slots need to be cut off and filed flat.

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Here's the completed re-aligned cams. I made the styrene pieces the correct size to space the cams correctly. Notice the holes where the cams would have been installed as compared with were they are.

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With the cams now installed correctly I wanted to see how the grippers line up. With the dumper in the load/unload car position, you can see the great distance from the top of the hopper to the opened gripper is quite large. The next step is to get the grippers down further.

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