Spindle bearing woes

@pontiac428 no need to apologise that's my bad for not knowing the proper terms I've just never heard it called the saddle before is all I've always known the saddle to be in the bed!
So I got the lathe back together I still have a ridiculous .01 of play at my part :( better than the .015 from before but still giving me an uncontrollable amount of chatter. I'll have to go the skimmed caps and grinded shaft route.
 
Here's what I'm getting... The up and down play is next to nothing but the side to side play is what's killing me.

IMG_20180930_153727.jpg
 
Hi Izzy,

I'm also clarifying ! The picture you posted, I've modified to show exactly where you need to remove bearing material.

The parts that have the bolt hole through will need clearance so carefully just file a few thou off the wide flat faces so that you have space for shims. The paint on the headstock part where the shim sits should be scraped off, it needs to be flat, otherwise it will tip the cap causing the shaft to be nipped at only one point.

When refitting, this is where your engineers blue helps.

IMG_20180929_144123.jpg
 
[QUOTE="Izzy,
So I got the lathe back together I still have a ridiculous .01 of play at my part :( better than the .015 from before but still giving me an uncontrollable amount of chatter. [/QUOTE]

10 thou is ridiculous ! You need to get that play down to a thou or less. From looking at the picture you posted of your turned surface, you have a lot of work to do !

You have removed so much material from the spindle bearing surfaces, that you are going to have a hard time getting back to the correct clearances.
 
Time for a beer...

Once finished cut the can to make shims to go under the bearings as this will close them up.

You will need to skim the ends to get vsps to Close

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@BaronJ you said I should take about 10 thou off the caps, couldn't I just do that in the Bridgeport? Seems like alot to file off.
There is no paint on the mating surfaces of the bearing cap. You mentioned the cap needs to be flat, it's got about a 20thou taper? the cap itself has pretty bad taper to it on its own should I try to get that out too?
 
Izzy, you should really stop trying to remove material. You're on your way to making a mess of the most sensitive part of a lathe. You won't get what you are after working with abrasive cloth, and certainly not "by eye". Bearings and spindles are something that require attention to the .0001" in squareness, roundness, thrust, and concentricity. It takes more than your bench calipers to measure. If you stop while you are ahead, you can probably still use those bearings and spindle- after they've been re-bored in a shop set up to do the job. Hopefully you haven't hit the point of no return with it.
 
Hi Pontiac, Izzy,

I fear that too much material may allready have been removed from both the spindle bearing surfaces and the bearing caps anyway. Without a gap between the faces that the bolts securing the caps go through, the bearings are not going to be able to collapse enough to grip the spindle.

Unless the headstock itself can be mounted on the mill and guaranteed to be square then taking a few thou off the top with a file is one option.
Unless you have a gap when the cap is fitted, there is no way that you can reduce the play in the spindle.
Once you have that gap the bearing can be closed up by very carefully rubbing down the cap faces.

Lapping split bearings using abrasive paper is very much a common way of removing very small amounts of material. But it takes some skill and a lot of time. The workpiece has to be kept flat and the downward pressure kept uniform across the work.

I also doubt that spare bronze bearing shells are available for this lathe, because new shells would be able to be adjusted to suit the spindle. That is assuming that the spindle is still round after being cleaned up.
 
I mostly just knocked off the tops of the ridges, I removed a thou or less of material I honestly didn't take off much. I did more polishing than anything else. I understand that the spindle is the most important part which is why I'm asking for help but you honestly don't need to be measuring in the tenths to see a 20thou taper. my point is if it's measureable with calipers then it's probably pretty bad considering it should be in the tenths as you said which it's no where near that. I'll take everything apart and get new measurements and report back. I may have found a shop that will be able to line bore the bearings so it's gotta come apart anyways.
@BaronJ unfortunately this was more or less the condition I got the lathe in a few years ago. When I first got it, all I did was adjust the shims and it ran great for the last 2 years or so the front bearing only had a couple thou of shim stock between the caps when I got it. The head stock does come off and it could be mounted on my mill it's only held in with 4bolts and it mates with the bed of the lathe so I would assume the bottom to be flat.
 
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