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Getting a platten off a motor spindle?

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Deadeye

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I'm trying, unsuccessfully, to remove a sanding patten from the motor spindle.

I have managed to remove a bolt that runs through the neck of the platten onto the spindle; I thought this was locking it but seems not.

There is a keyway in both the spindle and the disc hub; these are aligned. I can't see a key in the channel at either end. If I poke a small rod in at the front it hits what feels like a surface running diagonally out away from the axis - i.e. the rod skids outwards (when I'd expected it to hit a flat key head).

I've tried heating; I don't have a puller that can get the ends of the 12" disc (not even close).

Some newbie questions (as ever):
1. If there is a key in the channel, do I tap it inwards from the front towards the motor, or is it some perverse setup where I have to push the platten in and then get the key out away from the motor?
2. If it is a key and needs to go towards the motor, do I just keep tapping gently until it shifts?
3. Any other tips/techniques?

4. Bonus. The motor is wired to run anticlockwise... which was unexpected. The sanding table is L shaped so it turns down into the corner of the L. Is that right?

Thanks!!
 

jimmy_s

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More than likely there will be a key in the keyway - the key may well have have rounded ends - fairly common where a vertical mill has formed the keyway in the motor shaft. Your wire might be moving to either side of the curved end of the key?. I would try heating and perhaps spraying with WD40 or similar to try and help loosen it.

I would think that you will either need to use a puller or support the disc/ with the motor hanging under its own weight - and tap the end of the motor shaft with a brass punch or similar to try and get it moving.

Good luck ! can be a pig to get these things apart. Suppose thats why things like taperlock bushes were invented.
 

Myfordman

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Be careful not to distort the disc with pullers homemade or otherwise. I’d be tempted to try folding wedges between the motor face and the boss of the disc. Plus gas is far far more effective than wd40.
 

Argus

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Keyway?

With Wodruff keys there may be a recessed (sometimes hidden) screw holding down the key in its slot.
They may be held down with an Allen screw through the collar and occasionally there may be a second locking screw below the first, so if there is one, take it out the first and look inside the recess to be sure

Otherwise, if it is dissimilar metals, giving a a solid-cold-welded-jam-fit..... good luck! Gentle, strategic heat may release it more effectively than brute force.

Good luck.
 

Deadeye

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Well....it's off!

I did a triple combination - motor hanging below platten and platten on supporting blocks. Twin wedges and some heat to the boss.

On inspection, the keyway was full of glue. Also I think the key may have been in the wrong way round - the tapered end was outwards. Finally, the retaining screw was pressing against th emain spindle, and not holing down the key.

Anyway, I've stripped and cleaned all the parts, decided against a repaint, and it's all wiped with oil and ready to put back together!

Thanks again for the help.
 

jimmy_s

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Glad you got it off ok - can be a real struggle. The glue may have been shaft lock/ retaining compound - like locktite 638 or similar which may also explain why the shaft was reluctant to part company with the platen.
 
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