Thanks for the reply CT2,
At this point I'll most likely stick with shims for now - I have the carriage and cross slide all set with no noticeable play, and they both slide extremely well. I found a video where a fellow was trying to improve his mini lathe carriage, and it had the 2 set screws for the clamps for adjustment - anyways he ended up cracking his clamps and reverted to using shims - so it's probably the more sound approach as you mentioned - full contact along the entire clamp.
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I decided to go with the bronze sleeve bearing, and it is working perfectly now. I enlarged the 1/4" hole in the cross slide casting with a size T drill bit, and was able to fit the bearing in quite snuggly, however I'll take your advise and install at least 1 set screw to secure it before doing any work on the lathe. There is no almost no noticeable slop at all as far as I can tell ( not an expert at any rate and will probably have a much better idea when I actually use this for some work when the lathe is done ).
I don't have the miller book so I have no idea what the 2 part compound you are referring. I do notice that most cross slides on commercial lathes have a solid carriage and the feedscrew & crank are all part of that - possibly the cross slide has a threaded bottom to allow the feedscrew to drive it ( notice the carriage ways are typically U shaped ).
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Thanks again for the reply,
Morgan
--- In gingery_machines@yahoogroups.com, "Brite" <coldtoo2000@...> wrote:
>
> Hi Morgan,
>
> Progress is always good news!!
>
> Shims are a pain to get adjusted, no doubt about that. But they give you good contact along the slide to control chatter and once set up, should last a good while before wear forces adjusting.
>
> One favorite mod on the Cross Slide (and Top Slide) is to mold them in 2 parts like the Compound slide on Milling machine. You may be able to cut off the "bracket" leg and replace it w/ a new casting if you wish, but I think a sleeve bearing will work if you can't get it filed square. You could secure the sleeve w/ a setscrew so it won't slip around in the tang.
>
> Also, remember there is always some slop in this type of feed screw. You work around this by always approaching your "setting" from the same direction. So in your example you want to back off 10 thou. -- so say you are at 50 now, you want to back off to 30 or 20 or so, then feed IN to 40. this will "take up" any play in the feed.
>
> Hope it makes sense,
> CT2
>
> --- In gingery_machines@yahoogroups.com, "mindviz" <mindviz@> wrote:
> >
> > Hey Guys,
> >
> > I've actually been making pretty good progress with the lathe in the past month or so; will have some photos and possibly a video posted soon ( might be casting again soon yay ).
> >
> > I did have a question, as the adjustment of the carriage and cross slide box slides have made me wonder about Gingery's method of using shims to give the box slides as close a fit as possible.
> >
> > For me shims have become a major time consumer, though it seems like once I get them right I won't have to make any adjustments for a while - which is probably the main benefit of using shims, however in researching some of the mini lathes on the market, it seems like most have some type of slide plate that rests above the clamp and has adjustment gibs to bring it in close contact with the ways. This definitely sounds appealing to me, as I wouldn't have to worry about making any additional shims when I need to compensate for wear - I was wondering if I could simply buy some thin brass stock and drill holes in the clamp pads for 3 set screws each to have a similar setup?
> >
> > At any rate I was curious what everyone thought on this, or if anyone had given prior thought to modifying the slides such that they have slide plates with gibs?
> >
> > ---
> >
> > While I have you also I had another question with regard to the cross slide feedscrew assembly. The casting where the feed screw goes through the cross slide casting and is secured with set screw collars isn't perfectly square, and thus there is a delay before the screw moves the carriage when cranking it one way ( slight gab at part of the angle on the inside, the outside edge seems fairly square to the feedscrew ). This seems like it would be a big issue if I was to convert to CNC, or even add a graduated dial for my own reference - ie: if I stopped and wanted to back off by .01 or something, I'd have to back off until the carriage started to move and then note the dial position before proceeding.
> >
> > Anyways, what I'm thinking I will do to fix that that is either to file the casting square on the inside, or it seemed like an easier approach would be to enlarge the 1/4" hole to accept a sleeve bearing ( would need it to be pushed in snuggly with no play ) and then have the set screw collars on either side of that in close contact. Seems like brass or bronze would be a better wear surface than the aluminum casting as well.
> >
> > I also noticed some mountable bearings I thought might work however the casting would have to be perfectly square for them to work, same with go with a flanged sleeve bearing. Was curious what your thoughts were on this - if my idea will work fine or if there are any other alternatives that would work better before I modify my cross slide.
> >
> > Thanks,
> > Morgan
> >
>
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