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Thread: Drill Press Pulley removal

  1. #1
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    Drill Press Pulley removal

    My old-ish (1980's?) craftsman drill press that I bought used about 5 years ago has given me problems on and off with the pulley at the motor. The pulley doesn't stay tight on the motor shaft and therefore power doesn't transfer to the other pulleys and to the bit. I realized today after trying to get the pully off and try and really fix this issue instead of just tightening the set screw, that there isn't a key in in the pulley against the motor, and the set screw tightens directly against the shaft. So I'd like to remove the pulley and put in a key, hoping it will keep the pulley on tight. But I'm afraid that when the set screw loosens up and motor shafts spins inside the pulley, that it may have cut into the shaft keeping the pulley from being removed.

    After removing the set screw, the pulley is loose and moves up and down about 1/8" and wobbles back and forth but it won't move any further up. Do I need to buy a bearing puller to get it off?

    My DP is listed as a 17" 1.5hp (max develped - motor says 10A). There's a Grizzly G1200 DP listed for sale locally for $70, but it's only a 14" 1/2HP machine. I thought about simply replacing the DP, but I'd like to see if I could fix the c'man first.
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  2. #2
    Setscrew has burred the shaft. Make sure there isn't another setscrew, then get a cheap puller from HF and pull it off.

  3. #3
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    What about trying to insert a key without taking off the pulley? If there's a keyway at the top of the pulley and you can align it with the keyway on the shaft, it shouldn't 'be hard to slide in a new key.

    You have to be really careful when pulling of a cast alley pulley with a gear puller. The metal crumbles very easily. If you go that way, try to support the back of the pulley with some scrap wood, etc.
    Last edited by david brum; 11-21-2012 at 8:21 PM.

  4. #4
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    Second to David about that pulley being fragile and easily damaged. It looks like cast aluminum. However it doesn't sound like it should be that tough to get off since it is moving. If you go to Harbor freights site and search for a bearing puller/separator you will find a 2 piece pulling assembly designed to be used for pulling bearings but could safely pull your pulley. It would spread the force evenly around the pulley. However I don't know if you want to spend that much for possibly a one time use. You would also need a puller to attach to it. It might be cheaper to just replace the pulley if you damage it. Under $20 on Amazon for a similar pulley. I don't know your diameters but a possibility.

  5. #5
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    Let me highlight something John said that you might have missed. Make sure there isn't a second set screw in there under the first one! I had a Craftsman step pulley like this one that had two set screws intentionally stacked on top of one another (presumably the second one was a jamb screw). If there is a second one in there, it will have to come out before you pull the pulley, or you will be in for a world of pain (DAMHIK). You probably don't have the second screw, but just make sure first.

    Also as mentioned, Craftsman step pulleys are particularly soft, and you can do a lot of damage quickly with a puller. Use a three jaw puller instead of a two-jaw, and be very careful not to bend the pulley. Stop if it starts to bend. Again, yours sounds loose, so this probably isn't a big problem.

    Most likely, it is a burr on the shaft that is holding things up. Not much you can do about that. You might be able to fiddle it around a little and use the set screw to mash the burr back down a bit. Otherwise you probably have to just force the pulley off.

    You mentioned putting a key in. Do the shaft and pulley already have key slots and you are just missing the key? If not, how do you plan to make the slots? Another option would be to just file a flat on the shaft for the set screw to seat against. Add some Loctite and it should stay in place. Check that your pulley itself is not cracked around the screw. I have had that happen too. Once the casting cracks around the threaded hole, you can't get any force out of the screw -- it just opens the crack.

  6. #6
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    Quote Originally Posted by Ryan Baker View Post
    Another option would be to just file a flat on the shaft for the set screw to seat against. Add some Loctite and it should stay in place.
    That was going to be my suggestion...
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  7. #7
    Matt, The pulley probablly needs to be replaced. As it spinns on the shaft, the bore of the pulley opens up, causing the wobble. You might also have damaged the motor shaft. You might get lucky with the motor shaft. I would get it apart,
    the pulley sounds like it is done. Measure the shaft diameter, check its condition. Check your cost of pulley replacement
    and possible motor replacement (worst case). Then you can make the call. A key will drive the pulley, not the set screw.
    Most pulleys have the set screw over the key, for easier removal. Hope this helps, good luck.
    Ellery

  8. #8
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    Along with what Ellery suggested about the pulley bore is likely worn significantly. That isn't all bad because that is better then the motor shaft being worn undersize. A typical key set up in an application would be a Woodruff key. The half moon shaped style. If there is none an option to the flat on the shaft that is effective and easily done would be to position the pulley where it needs to be and then take a drill that is "tap drill size" and going through the set screw hole dimple the shaft. If your careful you can take it a little deeper in place or slide the pulley back off and do it. The set screw is cone shaped on the end and will lock solidly into this. You really don't have to go much deeper and I wouldn't then when the full diameter of the drill bit engages the motor shaft. If it has a key seat or key way depending on type used you are probably going to find it damaged from the set screw and you will have to dress it to get it to accept a key again. Keep us posted on this. Good Luck and Happy Thanksgiving to all.

  9. #9
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    Here's a picture from above. There is not a receiving slot for a key on the motor shaft, but there is obviously one on the pulley. So maybe my idea of adding a key isn't what's needed. And thinking about it some more, is it odd that the motor shaft isn't more flush with the top of pulley?

    I like Ronald's idea of drilling a hole to receive the set screw, and also that it would mean I wouldn't need to take off the pulley. And there definitely isn't another set screw in there

    Any other suggestions? Thanks so far for all the ideas - next time I'm at HF I'll pick up a bearing puller anyway.
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  10. #10
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    That is typical of a woodruff key setup. The key would have been hidden from sight as well as the key seat in the motor shaft. It shouldn't have lost out but it might have sheared at some point unless it was never there.

  11. #11
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    I got a bearing puller from Autozone and went at that pulley. It took some effort and I was worried about the aluminum pulley exploding, but I took my time and it came off without damage. As you can see, the set screw did indeed burn a groove into the motor shaft. There is no woodruff key, but only a flat on the shaft, so I took Ronald's advice and drilled a divot to give the set screw a place to settle into. The DP is back in action - thanks all!
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  12. #12
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    I never thought of getting a puller at one of the auto parts stores. Better then buying something you might never use again. Looks like you are in business. Glad it was a relatively easy fix.

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