# HELP! G0602 Problem



## sepulling (Oct 12, 2013)

I'm really hoping someone can help me here because I'm completely lost. I was trying to turn some 3" O.D. cold rolled tonight and noticed my lathe wouldnt even take a .010 pass it just chattered really really bad. I did all the common sense stuff like double check tool height etc etc, then noticed I could move my cross slide in and out I'd say probably .010-.015" by hand. I'm assuming this is where the chatter problems are coming from. So I went over it all and adjusted the gibs and backlash and everything, still no difference. Took the compound off and noticed that I couldn't move the cross slide anymore. So I put the compound back on and tightened it and it was back. Then I just loosened the compound and the movement was gone again. Its something happenning when the compound is tightened but I can't figure it out. Sorry for writing a book and thank you all in advance for any input.


----------



## itsme_Bernie (Oct 12, 2013)

To be clear, I do not own one.  But I wonder, listening to your story, if a casting is cracked or something.  I can't image why tightening or loosening the compound would affect the crosslide.  I looked at a few pics online, and not obvious to me.
Is there a part that could have come loose underneath that fastens the compound?

This isn't the first thing I would suspect, but your issue sounds rare.

Is the crosslide nut on tight?

I am sure someone with your machine would know more about how it is built.


Bernie


----------



## Chuck K (Oct 12, 2013)

My first thought would be a loose fastener on your cross slide nut.  The compound thing is kind of perplexing though.  You already checked the gib.  I don't know how the backlash is adjusted on cross slide screw on that machine.  I would guess either at the dial on the front or with lock nuts at the rear.  I would check the nut and the lash adjustment and then try to factor the compound in to the equation.
Chuck


----------



## sepulling (Oct 12, 2013)

I was (unfortunately) thinking something is cracked too Bernie. I had the compound off and cleaned it all and didnt see anything. I'll take a look again tomorrow at the cross slide nut and see what I can find. It could've been like this for for a while since it doesnt do it in aluminum (atleast noticably) and I dont turn all that much steel. Thanks guys for your quick and helpful responses!


----------



## CNC Dude (Oct 12, 2013)

Have you tried different speeds and/or rates? If you use the same parameters for Aluminum and Steel, chances are one or the other will behave like a demon wanting out of hell.


----------



## sepulling (Oct 13, 2013)

No I definitely don't use the same speeds/feeds for steel as i do for aluminum..... demon wanting out of hell  now thats a new one :rofl:


----------



## Chuck K (Oct 13, 2013)

I reread your original post.  You don't state how old this machine is.  What size is it?  If you have adjusted the gib and the lash and the nut is tight, then I would suspect wear in the nut or screw, or both.  Is it possible that this machine has a very light cross slide that is somewhat flexed when you tighten the compound?  Maybe enough to bind the screw and nut and cancel out some of the back lash. I doubt that .015 lash is enough to create the chatter you experienced.  I'm thinking its more of a tool geometry problem and speed problem.


----------



## itsme_Bernie (Oct 13, 2013)

Chuck K said:


> My first thought would be a loose fastener on your cross slide nut.  The compound thing is kind of perplexing though.  You already checked the gib.  I don't know how the backlash is adjusted on cross slide screw on that machine.  I would guess either at the dial on the front or with lock nuts at the rear.  I would check the nut and the lash adjustment and then try to factor the compound in to the equation.
> Chuck



Wow Chuck- 

I didn't know there was a backlash adjustment in that machine.  If so, it really sounds like that for sure!

Bernie


----------



## sepulling (Oct 13, 2013)

Its a grizzly 10x22 bench top lathe, it has the backlash adjustment on the handle, but theres also adjustment on the cross slide nut itself. Problem is I have to remove the compound the adjust the cross slide nut. I decided to take it apart and inspect the screw and nut today, think I found at least part of the problem, this is the screw and the cheaply cast nut that broke. Not exactly sure how this setup is supposed to work maybe someone can educate me because the grizzly manual is horrrible. The socket head cap screw goes down through the top of the cross slide into the nut, then theres a pointed set screw that goes in the part thats broke.


----------



## epanzella (Oct 13, 2013)

sepulling said:


> Its a grizzly 10x22 bench top lathe, it has the backlash adjustment on the handle, but theres also adjustment on the cross slide nut itself. Problem is I have to remove the compound the adjust the cross slide nut. I decided to take it apart and inspect the screw and nut today, think I found at least part of the problem, this is the screw and the cheaply cast nut that broke. Not exactly sure how this setup is supposed to work maybe someone can educate me because the grizzly manual is horrrible. The socket head cap screw goes down through the top of the cross slide into the nut, then theres a pointed set screw that goes in the part thats broke.



Where was your access to the pointed set screw when everything was assembled? My G4003G setup looks similar to yours but the setscrew access is from the side facing the headstock.


----------



## sepulling (Oct 13, 2013)

Its actually in the picture there, its right on top of the cross slide right below the counterbored hole.


----------



## Chuck K (Oct 13, 2013)

I've seen split nuts, but I haven't seen one exactly like that.  Are you sure it's broke?  I'm looking at the pic trying to figure out how it works.  Does the set screw push the piece down to kind of bind the threads and tighten the motion?  If you had the nut fastened in place and the piece inserted with the set screw holding it, could you start the screw and then tighten the set screw after you had the cross feed screw through the nut?  If it wasn't in two separate pieces I don't see how it could work.

Chuck


----------



## markknx (Oct 13, 2013)

If I recall right from mine the pointed set screw spreads the two halves of the split nut to take up slack on the screw. it was eiter over tight or or faulty, or shock loaded.





Chuck K said:


> I've seen split nuts, but I haven't seen one exactly like that.  Are you sure it's broke?  I'm looking at the pic trying to figure out how it works.  Does the set screw push the piece down to kind of bind the threads and tighten the motion?  If you had the nut fastened in place and the piece inserted with the set screw holding it, could you start the screw and then tighten the set screw after you had the cross feed screw through the nut?  If it wasn't in two separate pieces I don't see how it could work.
> 
> Chuck


----------



## Chuck K (Oct 13, 2013)

Never considered that.  It makes sense that it would work that way.  Not the best design, but it should work.  I think I would just make a regular solid nut for it and call it a day.

Chuck


----------



## sepulling (Oct 13, 2013)

Yeah it's definitely broken, that would actually be a side view of how it goes in, the smaller piece is what was broken, it almost looks like the set screw is supposed to wedge in the gap and like you said allow it to tighten up on the threads of the screw. The socket head cap screw is actually what they describe in the the manual as the adjustment screw and the set screw isnt even mentioned. Like I said the manual is horrible lol. Here is an exploded view..... I ordered a new one but still dont know how its supposed to be adjusted correctly


----------



## markknx (Oct 13, 2013)

well you don't want it so tight than it feels in a bind. it should have a few thous of lash but not more than 5




sepulling said:


> Yeah it's definitely broken, that would actually be a side view of how it goes in, the smaller piece is what was broken, it almost looks like the set screw is supposed to wedge in the gap and like you said allow it to tighten up on the threads of the screw. The socket head cap screw is actually what they describe in the the manual as the adjustment screw and the set screw isnt even mentioned. Like I said the manual is horrible lol. Here is an exploded view..... I ordered a new one but still dont know how its supposed to be adjusted correctly


----------



## markknx (Oct 13, 2013)

sorry that gotposted in the wrong topic(deleted)


----------



## Tozguy (Oct 25, 2013)

sepulling said:


> Yeah it's definitely broken, that would actually be a side view of how it goes in, the smaller piece is what was broken, it almost looks like the set screw is supposed to wedge in the gap and like you said allow it to tighten up on the threads of the screw. The socket head cap screw is actually what they describe in the the manual as the adjustment screw and the set screw isnt even mentioned. Like I said the manual is horrible lol. Here is an exploded view..... I ordered a new one but still dont know how its supposed to be adjusted correctly



The Grizzly manual for the G0602 lathe has the adjustment procedure on page 60.


----------

