Logan 820: How do I lock the cross-slide and compound?

OK. I guess that I am too used to dealing with Clausing where, if they no longer stock the part, they almost always have the original drawings (at least for the lathes - less so for the mills and shapers).

In that case, the first thing to do would be to check the angle on the tip of the Nylon Patch or Nylon Rod gib screws that he was sent. Be sure that it is the same as on the spotting drill and that the spotting drill just fits through the tapped gib screw holes in the side of the cross slide.

I would suggest acquiring a roll of 0.005" and 0.010" shim stock and cutting enough strips to approximately center up the gib top to bottom in the slot that it fits into. Shim both below and above the gib. Use three round nose set screws to lock the gib immobile in the slot. Spot drill the first hole, move one of the screws to that hole and drill the second one, and so on. Then move the gib to the drill press and use a drill bit the diameter of a body drill for the screws and with the same included angle on the cutting end to enlarge the spot drilled hole to the diameter of the screws. Use a depth stop to get all four holes to the same depth which, absent instructions to use something else, I would make around the depth for the body drill to be cutting to the full diameter.

To pre-position the gib vertically for getting the gib screws into place, I would use the shim pack that was under the bottom of the gib for step one above.
 
Tell me if this make sense...

Step 1.pngStep 2.png

So drill and ream the first hole, then drill and ream the second so the 2 holes intersect at 90 degrees, size is dependent on just how big your lathe is.
The second hole, from the side drill and ream thru an inch or so, and then thread the first 3/8 of an inch or so.

Next step take dowel pin, grind one end on a 45 degree, then make it so that the high side of the 45 degree end it fits at or near the top of the line of the horizontal hole. Make a second dowel, again with a 45 degree end to go in the side hole, the 2 angles meet and the screw applies pressure to the lathe making a nice stop. Get fancy and create a step in the vertical pin to allow a small spring to pull the pin from the base making it spring back up off of the main lathe. Personally, I have this on the wrong end of the cross slide as being on the back side is best. The front could allow the pin to drop out if the slide is brought too far back.

Yell at me if I messed up..
Regards

Richard
 
Tim,

I've been away and just looked thru this thread.

I have some spare Logan parts and noticed that the cross slide from a Logan 210 uses a gib locating pin and the same style conical screws that Logan provided you. This particular gib has no seats cut into it (but dimples on the back side from contact with the adjustment screws), and just one through hole placed to match a 1/8" gib locating pin mounted in the cross slide. Here's a pic.

InteriorView.jpg

There appear to be quite a few different ways to locate and apply pressure to the gib plate.

One other thing - I inadvertently used long screws at the two locations for the cross slide screw cover plate (you can see the bottom of the tapped holes on the left side of the cross slide in the pic). If those screws happen to contact the carriage casting, it can cause travel and gib adjustment troubles. Not sure if this has been mentioned. Easy to fix with a few washers.

Good luck with the troubleshooting.

TomKro
 
TomKro,
That's interesting. I don't think the chip cover screws go through but I'll certainly check tonight.
thanks,
Tim
 
Tim, just checking, are you aware there is a Logan group Scott moderates? Also several members there who have been working on the 200s & 820's for decades. There are a couple of recent discussions on the cross slide dials that cover the little adjustment possible with the two nuts. I don't recall any gib discussions in the past couple of years, but they could be some in the archives. I can't get the link thing to work, but it's groups.io/g/lathe-list
 
[QUOTE="ThinWoodsman, post: 665157,

Out of curiousity, for people having trouble getting links to work, is that when using a phone on this page? I've never had a problem with the little "insert link" button (the two-link chain).
[/QUOTE]
Yes. And trying to balance turning the JS on and off. Not bad here, but on another site it can take literally 2 min for a page to load.
 
Shiseiji, TW -- thanks, yes I know the Yahoo forum and have new topics come into my email. But I had not thought to search it! It's interesting that the yahoo boards are what the internet used to be...one forgets so easily. And, it's also interesting that this is where Yahool started, and where it's ending...
Tim
 
Quite a few of the Yahoo groups have moved to groups.io because of no tech support on Yahoo since 2016. Most kept their same base names except that any underlines in the names were replaced with hyphens as groups.io doesn't allow underlines. Which is actually good as most email managers underline links . So the underlines don't show up.
 
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