PM30 bearing replacement.

theNOTORIOUSmo said:
It actually worked really well. Run out was barely moving the needle on the tenths indicator and I was able to keep it spinning around 11k all day long without it getting hot.

The only thing i had to add was 3 or 4 mm worth shims on the top bearing as those are 4mm shorter if I remember right so I can get the preload set without bottoming the nut out.

I also completely removed the quill setup so I didn't need those other t bearings. I ended up turning the shaft on the spindle to accept a bearing which went in a plate bolted to the top to keep its rigidity. But that was because I wanted to remove any backlash and it was cnc controled and wanted to rigid tap. Side benefit was that the smaller bearing I used was much cheaper than those 2 bearings.
Click to expand...
Sounds great I'm planning to do the same thing, no reason to have a drill quill on a CNC and I allready own a proper bench drill :D
 
theNOTORIOUSmo said:
It actually worked really well. Run out was barely moving the needle on the tenths indicator and I was able to keep it spinning around 11k all day long without it getting hot.

The only thing i had to add was 3 or 4 mm worth shims on the top bearing as those are 4mm shorter if I remember right so I can get the preload set without bottoming the nut out.

I also completely removed the quill setup so I didn't need those other t bearings. I ended up turning the shaft on the spindle to accept a bearing which went in a plate bolted to the top to keep its rigidity. But that was because I wanted to remove any backlash and it was cnc controled and wanted to rigid tap. Side benefit was that the smaller bearing I used was much cheaper than those 2 bearings.
Click to expand...
Can you post a pic of the quill mod? I used similar bearings to the one you posted, really smooth compared to the old ones.
 


You can kind of see it there. So i turned the shaft so it would fit a bearing i already had on hand and I ended up just removing that cylinder that the shaft slides up and down in. The top bearing is what supports the shaft from bending under the belt torque and is bolted to the top of the head with a plate. Along with that plate also supported an air cylinder for the drawbar.

Unfortunately I never finished documenting the conversion as I just got to busy with life and making parts. I would give an overview of where it is at now, but about 2 months ago...



Well that open garage was mine...
 
theNOTORIOUSmo said:


You can kind of see it there. So i turned the shaft so it would fit a bearing i already had on hand and I ended up just removing that cylinder that the shaft slides up and down in. The top bearing is what supports the shaft from bending under the belt torque and is bolted to the top of the head with a plate. Along with that plate also supported an air cylinder for the drawbar.

Unfortunately I never finished documenting the conversion as I just got to busy with life and making parts. I would give an overview of where it is at now, but about 2 months ago...



Well that open garage was mine...
Click to expand...
Oooof
 
Well, I gave up on the angular contact bearings after the second set. I had a hard time getting the preload right because the top bearing was a very tight fit on the shaft. The second go around it was a little on the loose side and I had chatter, so those bearings are toast most likely. Then finally installed some Nachi tapers And it runs nice. I wish someone would build a robust BT30 spindle cartridge that we could just swap out.
 
theNOTORIOUSmo said:


You can kind of see it there. So i turned the shaft so it would fit a bearing i already had on hand and I ended up just removing that cylinder that the shaft slides up and down in. The top bearing is what supports the shaft from bending under the belt torque and is bolted to the top of the head with a plate. Along with that plate also supported an air cylinder for the drawbar.

Unfortunately I never finished documenting the conversion as I just got to busy with life and making parts. I would give an overview of where it is at now, but about 2 months ago...



Well that open garage was mine...
Click to expand...
Wow, that is crazy. Hope you made out ok with that!

Great idea on dropping the pulley and raising the bearings. Probably helps with the belt whine as well.
 
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