Need help making special drive belt installation tool for 371 Porter Cable belt sander

I have a 371 Porter Cable belt sander that has stopped working. The motor runs at full speed but the belt stops moving or slows down considerably when even slight downward pressure is applied. At first I thought that the drive belt was broken but it looks OK. I want to take the sander apart and look deeper for the problem. To do this the drive belt needs to be removed. Because there is no provision to remove the tension on the belt, (you can almost play a tune) it takes a $230 tool called an A19540 SRT installation tool to add/remove the drive belt. If I could find a picture of this thing, I might be able to make my own (much cheaper) but I haven't had any luck finding a picture or description on the Internet.

I have a picture of the drive belt:

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an assembly diagram for the sander:
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Sander.pdf .

Any advice on making a tool or procedure for adding/removing this belt on my own without spending $230 or sending it in to Porter Cable? I really like this sander when it works.

Reply to
jalbers
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Loosen the belt a bit: You have too much tension on it.

Reply to
RAM³

wrote: (clip) The

I'm betting it is a loose set screw securing the motor pulley. Can you see/reach it without disassembly?

Reply to
Leo Lichtman

Better PDF

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from

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The belt probably comes off easy enough when you loosen the driven pulley #25 and finagle the belt off the side of the pulley facing the case, putting it on is going to involve sliding the pulley back on the shaft while teasing each groove of the belt onto the next pulley groove, one by one.

Dave

Dave

Reply to
spamTHISbrp

I'm guessing that the tool has two pins, one goes down the hole of each pulley. One pin is fixed and the other has an adjustment to allow you to start with the belt loose and then move the pins apart to their final dimension. You would then slip both pulleys off and onto the shafts simultaneously.

Probably not too hard to build.

Reply to
rangerssuck

(...)

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The cork and platen assembly is a wear item. How does it look?

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--Winston

Reply to
Winston

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and an assembly diagram for the sander:
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Belt Sander.pdf .

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Reply to
JR North

replying to jalbers, Oldman wrote: I use a heavy shank screw Gun bit holder with the correct size hex head bit to fit the small pulley. Install the belt partially on the large pulley and then put the bit holder through the other end of the belt and start the hex bit into the pulley. Straighten up the bit holder and start the belt down on the small pulley as you turn the bit holder with a wrench. Work both ends of the belt onto the pulleys as you turn the bit holder. It wasn't as bad as I first thought it was going to be. Once I came up with using the bit holder trick now it is easy.

Reply to
Oldman

replying to Oldman, Madmax26 wrote: I used a 5mm Allen in the small pulley. Slip the belt on the large pulley about 2 ribs. Put the small end of the Allen inside the belt and into the small pulley. Start to turn the wrench while putting pressure on the belt with your fingers and work the belt onto the small pulley ribs. As it starts to climb onto the small pulley, it wants to come off the large pulley, so you have to keep pressure on that end also. I did it by myself, so it took a couple tries but I got it! Just take your time and it'll go! Madmax26

Reply to
Madmax26

replying to jalbers, Craig wrote: I had the same experience. The problem was the worm gear from the motor became disengaged from the drive gear that turns the drive belt pulley. So the motor ran, but the pulley didn't move. I had to take the sander apart to find that out -- accidentally pressed in the right place, and the gears slid back together. Of course, it happened again after some additional use, so I took it apart again to push the gear back. It appears there is too much slack in the mounts for the gears. Wish I could tell you how I took the sander apart to reach the gears, but I can't detail it accurately for you. However, an exploded parts view (online) helped me visualize how the sander is assembled, and so how to take it apart and put it back together. One cautionary note: If you disassemble the plate assembly, with its springs and levers for releasing and adjusting the sanding belt, you will have a very hard time lining everything up again and holding the spring-tension in place while you try to re-install and re-attach the plate assembly. If it is possible to reach the gearing without taking the plate assembly out, I haven't figured out how. All the internal parts are attached to one half of the body or the other half, so I pretty much took everything out to reach the gears.

Reply to
Craig

replying to jalbers, Craig wrote: I had the same experience. The problem was the worm gear from the motor became disengaged from the drive gear that turns the drive belt pulley. So the motor ran, but the pulley didn't move. I had to take the sander apart to find that out -- accidentally pressed in the right place, and the gears slid back together. Of course, it happened again after some additional use, so I took it apart again to push the gear back. It appears there is too much slack in the mounts for the gears. Wish I could tell you how I took the sander apart to reach the gears, but I can't detail it accurately for you. However, an exploded parts view (online) helped me visualize how the sander is assembled, and so how to take it apart and put it back together. One cautionary note: If you disassemble the plate assembly, with its springs and levers for releasing and adjusting the sanding belt, you will have a very hard time lining everything up again and holding the spring-tension in place while you try to re-install and re-attach the plate assembly. If it is possible to reach the gearing without taking the plate assembly out, I haven't figured out how. All the internal parts are attached to one half of the body or the other half, so I pretty much took everything out to reach the gears.

Reply to
Craig

replying to Madmax26, Woodwell wrote: Excellent advice. Took a couple of try?s.

But once I understood the principal,,,,,,

You made me look real smart!!!

BTW. 4mm Allen key

Reply to
Woodwell

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