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  1. #21
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    I'm not looking for a full perfect rebuild at this time. Just looking to make some modest improvements. So while I got table and saddle off, I'd thought I'd try to improve the contact surfaces a bit. Then add some bearing surface to the saddle on both sides, for its mating surface to knee, and to table.

    I'm not going to mess with the dovetails at this time, not too much anyway. Mostly I just want to improve rigidity on flat surfaces.

    All the surfaces I ran a couple of scraping passes, mostly just to break the shiny surfaces up and get high spot lines down. Then starting with a straight edge on knee, we can see the only contact area is on outer edges. Using a feeler gauge I was about .004" at lowest spot in the middle, on both sides.

    48.jpg

    After spending good number of hours on it, I got the center low spot on both sides down to about .002". I scraped both sides the same number of times, doing one, then the other on every cycle.

    Working the mating surface on saddle I made nice progress, maybe 35-40% better contact area with the straight edge. Besides the straight edge, I periodically blued the knee and shoved saddle around on it. In the pic you can see my contact area is not 100% yet on the four contact areas, but when pushed on saddle it is damn close to 100%. I added some flaking and will roll with it. Not perfect I know, but improved.

    49.jpg

    I had leveled the machine about 6 months ago. I also made a minor leveling adjustment with table and saddle off. Now before scraping top of saddle and table I wanted to check where I was, in case I want to scrape a little heavier one side or not.

    My levels are pretty well zero'd in, whether I flip it 180 degrees or not, I'm within .00025". Checking right to left on both ways I'm about as dead on as it gets.

    50.jpg

    Checking front to rear, I'm averaging about .002" high toward rear, or toward column. That is with knee lock loose. If I tighten the lock, the number improves in my favor by .0005". Regardless, I know the front way has a little more wear.

    51.jpg

  2. #22
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    Checking the top surfaces of saddle:

    52.jpg

    You can see my contact area is not too good. Also we knew from the level the front way was wore more. This is further confirmed with blueing touching the center relief:

    53.jpg

    To help improve the level reading, I ran several scraping cycles on rear way surface, and the two center relief areas only. Nice improvement, and from here, I will work front and rear simultaneously until front contact area improves quite a bit.

    54.jpg

    Shop assistant feigning injury over tripping hazards:

    55.jpg

  3. #23
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    Having stuck the saddle on knee I had tightened gib , so that saddle was stable and moved freely in center of knee. But the saddle would tighten and stop near either end. I put yellow paint marks on the ends of travel, then kept scraping and was gradually moving outward.

    After a while I removed saddle again, and worked it and knee. The final result there is I have full travel to front of machine, and move freely to the yellow mark closest to column, and thats with saddle gib adjusted nice. Also, I can't get a .0015" feeler gauge between straight edge and knee surface. The front was a big surprise as I nearly killed myself when I yanked saddle clear off machine my first try.

    58.jpg

    To get there I was alternating between using a straight edges, then checking the mating parts together. I'd blue the knee then run saddle over it.

    59.jpg

    Checking the saddle surface after one of those checks:

    60.jpg

    I did work the dovetail some, but not to a large extent. Doing a check on the gib, thought I might want to work that a bit, as it was arched pretty good:

    61.jpg

    Spending some time with it and getting contact area moving outward:

    62.jpg


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