[cuauhtemoc]

Hi,

Been trying to machine a spiral groove onto round stock using the Tormach 6 inch 4 axis. It was working fine until towards the middle of the cut the 4th axis STOPPED rotating. This happened twice already and I can't figure out why. I actually caught it while cutting, programming running, but the axis was not moving and the position numbers for it were not changing on mach 3 (though x was moving, so the part is now scrapped). I stopped the machine and rotated the table manually using the pendant. For a moment it didn't move, then I heard a 'clink' and then it moved. Is there a safety clutch or some kind of controller overload turn off feature? Maybe my 4 axis needs to be adjusted? Any suggestions?

I was cutting 1018 steel 5/8 round stock with a 3/16 ball, about .030 deep.

Thanks!

[TXFred]

Jog the table manually and see if it stops at the same point. You may have stripped a tooth off of the ring gear.

Frederic

[cuauhtemoc]

I rotated the table a few turns, works so far. I just took off the screw for the clutch housing and found a stringy piece of 'wire' in there. I think something stripped inside, so going to have to open up the 4 axis and do a mini-rebuild. I didn't know the manuals were updated on the Tormach site, the newer version online for the 4th axis is WAY better now.

[300sniper]

are you sure the table locks are unlocked? if the table is too tight, it will loose steps i've found.

[cuauhtemoc]

The table locks were loose, i keep one lever 'up' using a magnet, had it once fall into the lock position and like you said, it goes off step.

I now have the clutch housing off, there was some kind of wrapping in there, all squashed up, it looks like wax paper or similar. The short stringy wire was inter mangled with this paper. Maybe someone was rushing to go home at the factory! (Or they put no love into their labor )

Also, when the eccentric lock is turned ccw, the manual states I should rotate by hand, but all i feel is the backlash only to the worm gear. Should it move freely by hand??

[cuauhtemoc]

I think I found the problem, the coupling has 2 screws to clamp onto the motor shaft and worm gear shaft and it also has 2 set screws to set against the flats on the shafts. Well the set screw to the worm gear shaft was not 'set'. Since I have the 4 axis on the bench, going to figure out why the eccentric lever is not working right.

[SteveKoerner]

But you said the position numbers in Mach had stopped also. It's an open loop system so a mechanical problem in the 4th won't explain it.

[cuauhtemoc]

Whoops, just looked over the code, it was moving to a new position via Z, so there was no A motion on the line I stopped it at.

I am still working on taking the 4 axis apart, anyone ever do this? It's probably the same model as the Phase II 6 inch.

[nitewatchman]

I think I found the problem, the coupling has 2 screws to clamp onto the motor shaft and worm gear shaft and it also has 2 set screws to set against the flats on the shafts. Well the set screw to the worm gear shaft was not 'set'. Since I have the 4 axis on the bench, going to figure out why the eccentric lever is not working right.

My set screws were loose as well. Killed a helical gear being cut with Gearotic G-Code.

nitewatchman

[cuauhtemoc]

Here's a picture of the what's inside a Tormach or Phase II 6 inch Rotary table.

[compunerdy]

I had issues with mine as well. Taking it apart and seeing how everything works makes it easier to understand some of the issues. But I also have had issues where it was programmed to move and the movement did not happen even though it seemed to all move freely. I have not had this issue in awhile but plan to have Tormach run my code the next time I run into it and see if we can figure it out.