spindle binding (I think) on BP mill

[JimDawson]

My head also has all new bearings, but there is still a growl in the area of the small drive gear (large timing belt pulley) shaft. I need to tear mine down again and locate the problem. I have vibration also, but I know the motor shaft is bent so pretty sure all of it is coming from there.

 

[Cadillac]

Not saying Jim is wrong about testing the spindle. If you have v blocks it would be more accurate to check on them with those directly on spindle. Preferably on a known flat surface. When your measuring do you see a “lobe” in the shaft measurement?Or is it .007 difference? To much grease can do damage as much as no grease too. I would try to isolate problems by taking belts off and spinning each Assy. Could be multiple things seeing it was disassembled prior to sale.

 

[Technical Ted]

I don't know what the tolerance for run out is for the spindle splined shaft. Do you have a press for straightening it? If it were me, I would call H&W Machinery Repair https://www.machinerypartsdepot.com/ and ask them for their opinion. They have helped many owners out and take pride in doing so. Especially if you bought the rebuild kit there. It would be important to have an accurate measurement for run out before talking to them though... Or, they might even suggest a way to check it.

Two full tubes of grease is too much. It takes closer t 1-1/2 tubes. From Ilion's book, with the shift lever in hi, the grease should come about 1/2 way up the gear teeth. No grease on top of the bull gear. The pinion gear cavity should be full.

The noise could be coming from the clutch not meshing correctly in Hi gear. Does it make the same noise in low? If not, this is probably the issue. You can adjust the clutch mesh. See this other post: https://www.hobby-machinist.com/threads/bridgeport-j-head-noise.73218/#post-614788 This adjustment was discussed pretty well in that thread.

You could also put the spindle between centers on a lathe to check for run out. If you rotate it between centers and the bearing races run out, you know you have an issue.

Ted

 

[ddickey]

Are we talking quill or spindle. I'm assuming quill?

 

[Technical Ted]

Are we talking quill or spindle. I'm assuming quill?

That is a good question. When I read his original post, I "understood" him to mean that the binding was happening only in certain areas of spindle rotation. This lead me to agree that he might have a bent spindle, not a quill problem.

Maybe I'm wrong??? Diamond please explain better what it actually is.

Thanks,
Ted

 

[diamond]

That is a good question. When I read his original post, I "understood" him to mean that the binding was happening only in certain areas of spindle rotation. This lead me to agree that he might have a bent spindle, not a quill problem.

Maybe I'm wrong??? Diamond please explain better what it actually is.

Thanks,
Ted

Thanks Ted. Yeah it's the spindle. I tore it down and confirmed today it's got some bend to it. Just laid it on the bearings and there was .007 of runout 6" above the top bearing. As I reassembled the machine I checked the fit with the top belt housing off & the spindle in the quill and the splines sticking up through the bull gear. Got the same measurement.

High side & low side. 180 deg apart.

With it open that way I could definitely feel a place in the rotation where the spindle splines get a real tight fit in splines in the bull gear shaft. Turn it 180 and it actually has a bit of play. So I'm pretty darn certain this is causing some of my issues. My neighbor has an automotive shop and several sizes of hydraulic presses. I may get the guts up to try straightening it but yeah, I do think I'll wait and call Barry at H&W after the holiday before I do anything more. They are good folks.

-dave

 

[diamond]

Two full tubes of grease is too much. It takes closer t 1-1/2 tubes. From Ilion's book, with the shift lever in hi, the grease should come about 1/2 way up the gear teeth. No grease on top of the bull gear. The pinion gear cavity should be full.
Ted

Yeah I WAY over filled it. During my tear down today this is what it looked like when I pulled the cover.


I discovered when would switch it to low, all that grease I stuffed under the bull gear would get squeezed up on top of the bull gear and then when I shifted it back to high it was packing against the cover and I was getting resistance. It actually pressed the aluminum cover plate up into the timing pulley and was rubbing!

I scooped out a bunch of grease and cleaned everything up. That really did help things out. I do have the book and did the 1/2 way up the bull gear on high thing but I had also squirted a bunch of the grease under the bull gear in attempt to fill as much of the cavity under it as I could. I didn't understand not to use the whole two tubes that came with the kit. Turns out that was not the right way to do it. Of course there was no where for that extra grease to go. LOL Ted you're right, it was a good 1/2 a tube of grease I scooped out.

I ran it again with the spindle out and it was pretty quiet. Back in and the noise is there. If I can resolve the bent spindle shaft issue I should be in good shape.

 

[ddickey]

Aren't spindles relatively cheap?

 

[diamond]

Aren't spindles relatively cheap?

I guess it depends on relative to what. A new R8 spindle from H&W will set me back about half what I paid for the whole machine. lol

 

[Technical Ted]

... I do think I'll wait and call Barry at H&W after the holiday before I do anything more. They are good folks.

-dave

That's a wise thing to do. Please share with us what he suggests and keep us posted on your progress.

On straightening the spindle: If you're considering scrapping it out and replacing it, I don't see what you have to lose by trying to straighten the one you have (speak with Barry first). Be careful of the bearings! You'll need to have a way setup, hopefully near the press, where you can check your results after each tiny tweak... it will be very easy to over bend it. You'll need to identify the hi spot, mark it, apply a tiny bit of pressure to it and then check it with your indicator. Here's a video I remember seeing where a shaft is straightened. Not exactly like doing the same thing to a BP spindle, but you'll get the idea if you've never done this type of thing before.

Don't press on the spindle bearings! If you do end up getting a different spindle it might be tough getting the spindle bearing off the bent spindle without damaging them. Again, this is where H&W can help out. I think you posted you put brand new spindle bearing on the one you have and it would be a waste not to be able to use them on a potential replacement ($$$$$$).

Good luck,
Ted