G0602 cross-slide gib adjustment/installation after 6-bolt compound mod?

dewbane

Michael McIntyre
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I just finished doing a 6-bolt compound mod on my g0602 using the ready-made kit on offer from Belfanti Machine Works. The installation went very well, but reassembly hasn't gone as smoothly. After I put everything back together, I have to keep the gib screws extremely loose to allow the cross-slide to travel. They are much too loose, and any gains I got from the 6-bolt mod are canceled by the new slop in the cross-slide.

I already went back to the drawing board once, to make sure I had the gib installed correctly. I did not, in fact. I missed getting the adjuster pin into the slot the first time. now that I have corrected that, getting the cross-slide back on is much easier, but I still have the binding issue. I don't see how I could have bent the gib, but maybe I did. It also has a rough patch one one end. I originally chalked this up to the condensation-related corrosion problem I've been fighting, but it later hit me that I'm probably looking at scale that wasn't ground off, and the gib probably has a big low spot right there.

Maybe there's some trick to this I'm missing, like tightening the gib screws in a certain order or something. Maybe I need to read up on scraping my ways. I'm really not sure where to go from here, and I thought I'd ask for advice from more experienced folks. This is the first metal lathe I've ever handled, and I haven't had it very long.
 
I'm not familiar with your lathe. In cases like this, some pictures really help.

Jib screws usually have a small lock nut to set the position for final assembly. First, take off the little nuts, insert the set screws and lightly tighten them up evenly. Then start backing off all of them (evenly) until the mechanism moves freely. If that solves the problem, put the lock nuts on and do your best at holding each screw from turning while lightly snugging the lock nut.

Ray
 
I just went through my G0602 upon purchase (used). The gib screws are definitely sensitive to the final few degrees of tightening so maybe you just need to be careful about holding them with an Allen wrench as you snug the locknut? May also be worth lightly sanding the contact surfaces on something flat to make sure they are okay.
 
The original 2 bolt mount distorts the carriage when you tighten/overtighten the bolts. The 6 bolt plate doesn't do that (or very little) but your cross slide/gib might have worn in its old position.
Are there shiny spots on the gib? If you have a surface plate or something very flat such as glass plate or even thick MDF, sand the gib flat on emery cloth.
 
I just finished doing a 6-bolt compound mod on my g0602 using the ready-made kit on offer from Belfanti Machine Works. The installation went very well, but reassembly hasn't gone as smoothly. After I put everything back together, I have to keep the gib screws extremely loose to allow the cross-slide to travel. They are much too loose, and any gains I got from the 6-bolt mod are canceled by the new slop in the cross-slide.

I already went back to the drawing board once, to make sure I had the gib installed correctly. I did not, in fact. I missed getting the adjuster pin into the slot the first time. now that I have corrected that, getting the cross-slide back on is much easier, but I still have the binding issue. I don't see how I could have bent the gib, but maybe I did. It also has a rough patch one one end. I originally chalked this up to the condensation-related corrosion problem I've been fighting, but it later hit me that I'm probably looking at scale that wasn't ground off, and the gib probably has a big low spot right there.

Maybe there's some trick to this I'm missing, like tightening the gib screws in a certain order or something. Maybe I need to read up on scraping my ways. I'm really not sure where to go from here, and I thought I'd ask for advice from more experienced folks. This is the first metal lathe I've ever handled, and I haven't had it very long.

The six bolt mod was patterned after the mod that I did. https://www.hobby-machinist.com/threads/improved-g0602-compound-clamp.34796/

If your cross slide was working well before the mod, it should be working now. It comes down to something in your machining process or your reassembly. I haven't looked critically at the Belafonti product but on mine, the four additional holes are drilled and tapped through. A burr on the bottom will ride on the cross slide ways and as you tighten the gib the slide is pushed into contact with the ways. A burr will cause friction. Another possibility is some debris on the surface causing the same effect.

The 602 has ground surface ways. Unless your way are completely worn, there should not be a need for scraping.
 
I ran into the same thing after installing a solid tool post mount on my lathe. Make sure the bolts are evenly torqued and it should get easier with some use.
 
Hi Dewbane, I'd suggest measuring your crosslide ways with a mic and precision pins. This will tell you if there is a taper and you will have to adjust it by scraping so it is square to the spindle axis.
It should taper in as you machine towards the center to a value of around 0.0005" to achieve a concave depression.
Your gib should be near perfectly flat on the two sliding faces. Adjustment will be as mentioned by Ray C. Its a finicky thing to do, and should be set so its a smooth sliding action with minimum friction. Don't forget your way oil upon assembly. Use as much as you want. I put small recesses with my dremel where my adjusting screws contact, I find this better than a pin or screw in a notch. I also radiused the ends of my adjusting screws to match.
Cheers Alby
 
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If you can't figure it out I know a retired machine rebuilder who lives outside of Christiansburg. Send me a private message and I'll give you him phone number. You may know him. His name is Roger P___-o
 
https://www.hobby-machinist.com/threads/improved-g0602-compound-clamp.34796/That is probably what inspired me to do this mod. I had been planning it for some time when I stumbled across the commercial offering at LMS. I literally entered "g0602" into the search box by accident, and that popped up. I have enough projects to keep me busy for months without doing that mod from scratch, so I paid the convenience fee on that one.
If your cross slide was working well before the mod, it should be working now. It comes down to something in your machining process or your reassembly.
I guess I was looking for some repeatable procedure, like tighten the gibs in this order as tight as you can, then back them off this much. It seems to be much more nuanced than that. When I went out there to take the pictures, it seems better the third time I reassembled everything.

I haven't looked critically at the Belafonti product but on mine, the four additional holes are drilled and tapped through. A burr on the bottom will ride on the cross slide ways and as you tighten the gib the slide is pushed into contact with the ways. A burr will cause friction. Another possibility is some debris on the surface causing the same effect.

That's exactly what his instructions indicate. I didn't really see or feel a burr after drilling and tapping my through holes, but I skimmed the new holes with a countersink anyway.

The 602 has ground surface ways. Unless your way are completely worn, there should not be a need for scraping.
I've seen scraping come up a lot. This equipment is junk, because the ways aren't scraped, etc. I guess scraping is for machined ways. The ways do seem fine out of the box, and I'm not trying to hold much better than 0.010" tolerances on any of the stuff I'm making so far.
 
Somebody asked for pictures, so I went out, disassembled and reassembled everything, taking pictures along the way.

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