Index Model 645 Mill

Did you pump fresh oil thru all of the holes to push out all of the grease that someone filled it up with?

My 645 is equipped with a Bijur oiling system. Later, if you need pictures on how the oil lines are run, I'll be glade to provide some. I may be able to put together a list of all of the metering units and their sizes, too if you like. Ken
 
With the old zerks removed, I was able to clean the grease out of all of the holes with a combination of solvents, compressed air, Q-tips, gun patches, and patience. I didn't even try to clean up the old zerks themselves, new ones are cheap! Thanks for the offer on the oil system Ken.! If the mill proves to be adequate for my needs after I get it running, I'll take you up on that.

I should be able to make some big progress in the next few days. The thrust bearing for the knee screw finally came in today. Once that's in, I have everything ready to install the saddle and table.
 
I ran into a problem today and I could use some advise. Here is a picture of the housing that holds the bearings and gears for the right end of the table lead screw. You might remember from an earlier post that this housing had been repaired by brazing in the past.
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When I went to install the lead screw bearing, the fit was excessively tight. After I pressed it in, the inner race was noticeably more difficult to turn. So then I pressed the bearing back out and did some measuring. The outer race of the bearing measures 1.653" (42 mm). The bore of the housing varies from 1.648" to 1.663" (measured with snap gauges and a mic).

So I'm open to suggestions on how to fix this. The part will swing on my lathe, so I guess I could mount it on a faceplate and just skim the bore to remove the high spots. Obviously, I can't bore it perfectly round or then it would be too big. Any other ideas?
 
You've probably already thought of this but since you ask and as I'm not familiar with the bearing (take this for what it's worth then o_O) - have you looked around to see if there is a bearing available that has an over-size OD?

I guess that one could also bore it out in a big way and put a press fit "ring/plug" in and then bore to size/position.

Both would probably work but the over-size bearing would be the easiest, best looking, etc. if at all possible.

Sorry, not much help,

-Ron
 
That's a good thought, but... A quick search on the Grainger website shows the next size od available is 47 mm. If I bored it out to that diameter, I would be removing roughly half of the thickness of the housing (leaving about 0.1"). That seems too thin to me. What do you think?
 
T.J,

If I recall, the bearing is a slip fit in the housing. All its doing is providing support for the lead screw and feed rod. So if you bore it slightly large, it won't hurt anything. If you go too much, well, I would make a very thin bushing that would be a finger push fit in the housing and likewise with the bearing too. If you notice, there is two tapped holes for a couple of machine screws that were used to hold the bearing in place.

The flange part where it mounts to the table on mine is broken off. I was able to secure the broken off piece with a small socket head cap screw. The other mount is still broken off but is held in place with a bolt. Been like that for the last 13 years and hasn't come off yet. Some day I'll try my luck at brazing and attempt to fit it. Ken
 
I'm with Ken. If there is that little of area to work with I'd be looking to make a collar/insert.

-Ron
 
I got the bearing housing bored out today. Everything went well. Here are some pics of my setup.
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It was a little tricky to get indicated in since the hole wasn't round, but I got it done. As you can see, the hole cleaned up pretty well except for the one area that was really large to begin with.
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The bearing is now a nice slip fit in the housing.
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