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Index Model 645 Mill

4gsr

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#31
.....snip........ I'll look into the Bijur systems. Do you have any suggested suppliers?

I do have a question regarding building up the shaft. Since it is steel, would it be better to weld it (MIG) or braze it?

Thanks!
Either welding process should work. Brass may wear down quicker and put you back to square one.

Just thought of something, go buy a piece of 11/16" hex stock locally or from Speedy Metals, and just remake the shaft. Much easier and cheaper!

As for the Bijur lubricating stuff, there's lots of stuff on eBay for sale. In fact, there's a place out on the west coast that sell a Asian brand that is used on Acer mills. He advertises on eBay as Supra Machine Tool, I think. Easy to find his stuff. He may have a kit made up of all of the stuff needed to convert a knee mill over to automatic lubrication. Be prepared to spend upward around $300 for the necessary stuff to convert you mill.

When you get to that point, let me know and I'll try to put together a lube diagram of all of the points of lubrication needed with a basic list of items for a shopping list to look for.

Ken
 

Martin W

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#32
Depending on how bad it is worn, you could use a stick welder with a carbon rod and some bronze wire?
Martin W
 

T. J.

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#33
I think I will just make a new one from hex stock as Ken suggested. That project will have to wait until I get the mill put back together because it requires a woodruff key slot to be milled.

I got the ram off last night, but I forgot to take pictures :confused 3:. I'll post some later today.
 

T. J.

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#34
As I mentioned earlier, I got the ram off yesterday. I had been dribbling Kroil along the dovetail for about a week hoping to get it loosened up. I removed the bolts on each end that anchor the chain, and the ram moved freely. I was then able to remove the broken ram adjustment shaft and sprocket. I don't think I caused all of this damage, but I sure finished it off! Another part to make...
image.jpg

The top of the turret after a little cleaning:
image.jpg
The rectangular hole close to the center is where the sprocket sits and the chain rides in the groove. I didn't get a photo of it, but the chain is attached to the bottom of the ram. Along with the sprocket it acts like a rack and pinion for extending the ram. The square hole toward the bottom of the pic is for removing the T-bolts that hold the turret to the column.

The underside of the turret:
image.jpg

The top of the column: image.jpg
 

T. J.

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#35
Removal saddle was pretty straightforward. The hand wheel and dial were removed, then the bearing bracket which bolts to the front of the knee:
image.jpg

Then the screw is screwed out. This key was missing. I haven't had a chance to investigate what it is supposed to engage
image.jpg

The nuts for both the table and saddle lead screws are cast as one piece. It can now be removed:
image.jpg

I was then able to slide the saddle off. The knee was raised as far as it would go, then hoisted off.
image.jpg
I'll have to find a way to grab it closer to its center of gravity when I put it back on. :eek:

So now the mill is broken down into its major assemblies. I will start cleaning them and move them to my shop for reassembly. I was hoping to get more done today, but I ran out of propane for the heater in the barn. It's supposed to be warmer tomorrow, so I plan on attacking the column with some degreaser and a pressure washer.
 

4gsr

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#36
That woodruff keyway in the cross feed shaft you were referring to is for use with power feed if your mill was equipped with it. You're bringing back old memories when I had mine taken apart in pieces. Actually my dad had taken it apart when bought the mill left it that way and passed away before he ever got a chance to put it back together. I got stuck with putting the mill back together later.
 

T. J.

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#37
That woodruff keyway in the cross feed shaft you were referring to is for use with power feed if your mill was equipped with it. You're bringing back old memories when I had mine taken apart in pieces. Actually my dad had taken it apart when bought the mill left it that way and passed away before he ever got a chance to put it back together. I got stuck with putting the mill back together later.
Ok. Mine doesn't have a y axis power feed, so that's why there's no key. I'm scared that I'll forget how some piece of this thing goes back together before I get done. I can't imagine starting with a pile of parts and figuring it out from there!
 

T. J.

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#38
I got the column cleaned up. This is a photo of the left way. This is the worst damage that I've found on any of the ways so far. This is limited to about a 3 inch area.
image.jpg
 

Silverbullet

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#39
That woodruff keyway in the cross feed shaft you were referring to is for use with power feed if your mill was equipped with it. You're bringing back old memories when I had mine taken apart in pieces. Actually my dad had taken it apart when bought the mill left it that way and passed away before he ever got a chance to put it back together. I got stuck with putting the mill back together later.
Ken you know you wouldn't have let that mill go . After your dad did all the tear down , it may have been ment for you to do it. I have things from my pop I wouldn't take a million bucks for. Just holding them I relive every thing.
 

Silverbullet

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#40
Clean up the parts then Ck your damages. I'd polish them up stone the ways to take nice down to keep them from catching chips and hold them to make more damage. Get or make felts and keepers , cheap floor mats help keep chips out of the ways. Even if you can't afford the bijor oiler you can make your own with a decent pump oil gun hooked up to a block of feed lines. I've got old drip oilers on one of my mills , and 1/8" copper lines soldered in place to a block with six lines to it to spread it thru the machine. Lots of options while it's tore down , great machines good luck with your rebuild. You can bag and label parts so you know where they go , pics help too.
 

4gsr

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#41
I've used every thing from cardboard boxes to plastic butter bowels with their lids to the little plastic containers you get from Kentucky Fried Chicken to store bolts nut in. The butter bowels can be marked on top with a Sharpie with it's contents. Like you said, the freezer zip lock bags work nice too! BTW- the parts to my 645 mill, I had carried them thru three moves before I was able to get it back together! Carried most of the loose parts in 5 gallon buckets! Didn't loose anything in those moves. Now, I have two lathes mostly tore down, working to get them back together.
 

T. J.

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#42
Made a replacement ram adjustment shaft. I milled the flats with an end mill in the lathe by holding the shaft in a boring bar holder. Sure made me wish I had a milling machine...;)
image.jpg
 

4gsr

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#44
T.J.,

At least yours wasn't frozen up like mine was. I hate to beat on anything to get it out, actually, I had to grab it with a pair of vise grips and twist and pull at the same time to get mine lose. And that was after I got the chain loose and removed. Oh, if you need any of the short roll pins that are used to secure the chain, I have a bag of 99 of them. At the time Fastenal would only sell me a full bag of a 100 when I only needed 1 pin.

I'm glad I didn't twist on the shaft and broke as it happen on you. But going into it, I knew that that wasn't going to free the slide to move on mine. It was frozen up with rust and crud. Took lots of soaking with oil and such. I cleaned and honed the way surfaces of all rust before attempting the get the ram unstuck. Had to use a big 4 x 4 block and BIG persuasion tool to get the ram to move. Luckily, the way surfaces hidden were in good shape, very little rust. Once I move the ram as far as I felt safe to move it, I cleaned and oiled the way surfaces on the exposed end and force it back the other direction until it freed up. Once that was done, I fished the chain back under the ram and attached.

Ken
 

T. J.

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#45
I'm behind on posting photos. ;-)

I reassembled the turret and ram to give me a way to lift the base. I got that much moved into my shop a couple weeks ago.
IMG_0295.JPG
IMG_0307.JPG

Then I hit a snag on disassembling the knee elevation shaft. The collar that the hand crank engages, was froze up something fierce. Heating it and soaking it with Kroil were unsuccessful. There was only a 3/32 inch gap between it and the measurement dial, so I couldn't put a puller directly on it. I wound up making a clamp that would grab it and give me something to latch onto with a bearing puller.
IMG_0318.JPG

It was a hard pull the whole way. I got it to the end of the shaft and that gave me enough room to remove the socket head screws behind the dial that held the bearing flange to the knee. I could then pull the whole shaft out (after removing the bevel gear from the other end).
IMG_0320.JPG
IMG_0319.JPG

I then pressed the collar the rest of the way off of the shaft. There was some scoring on the shaft where the collar had spun at some point. That was what made the removal so difficult.
 

T. J.

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#46
Here's some pics of the clamp I made and a close up of the scoring on the shaft
image.jpg
image.jpg
 

Chuck K

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#47
The clamp idea is great. Looks like your shaft needs a little love. Maybe braze it and turn it smooth.
 

4gsr

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#48
Oh Yeah, your supposed to remove the set screw from the beveled gear before removing the shaft.
 

T. J.

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#49
I got the knee put back on Saturday. This time, I put the straps on the front and back of the knee, rather than the sides. This kept it a lot more level. Right now, it's still suspended with the hoist since I'm still waiting on the new thrust bearing for the screw to arrive. The crank shaft is installed with new bearings.
image.jpeg

I'll try to post the numbers of the replacement bearings that I use in case someone else could use the info. For the knee crank shaft:
Outboard = Koyo 6203
Inboard = Peer 6003

Slowly but surely...:)
 

T. J.

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#50
I was making notes for myself last night about each zerk on the saddle lubricates, since it's not very apparent on some of them once everything is assembled. Then it occurred to me that this info might be of value to someone who hasn't disassembled their mill. So here are some annotated photos of the saddle with each zerk labeled. If it says "way", that means the horizontal surface (when the machine is assembled). "Dovetail" means the angled surface.
IMG_0402.JPG IMG_0403.JPG IMG_0407.JPG

Sorry about the cluttered background. In the first two photos, the saddle is sitting vertically with its front side up. For now, I'm replacing all of the zerks. I may install an oiling system later.
 

4gsr

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#51
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
 

T. J.

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#52
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.
 

T. J.

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#54
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.
image.jpeg
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?
 

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#55
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
 

T. J.

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#56
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?
 

4gsr

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#57
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
 

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#58
I'm with Ken. If there is that little of area to work with I'd be looking to make a collar/insert.

-Ron
 

T. J.

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#59
I got the bearing housing bored out today. Everything went well. Here are some pics of my setup.
image.jpeg image.jpeg
image.jpeg

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.
image.jpeg
image.jpeg

The bearing is now a nice slip fit in the housing.
image.jpeg
 
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