I used the OD arc 3 wizard to generate the following code.  All of the code is not listed just the part leading up to the problem.  The G-code roughs the part OK (it looks like a ball on a rod).  When it gets to the I and K part in the finish cut, it cuts right through the ball and leaves a smooth cut like it was a straight G1 move.  It appears to display properly in the preview window.  Any idea what could be wrong (I am still working on learning I's, J's and K's).

G1 Z-0.1196
G0 X0.155 Z-0.1096
G0 X0.195
G0 Z-0.1904
G0 X0.155
G1 X0.135 Z-0.1804
G1 Z-0.198
G0 X0.155 Z-0.188
G0 X0.195
G0 Z-0.09
G0 X0.125
G1 Z-0.1184
G0 X0.145 Z-0.1084
G0 X0.195
G0 Z-0.1916
G0 X0.145
G1 X0.125 Z-0.1816
G1 Z-0.198
G0 X0.145 Z-0.188
G0 X0.195
G0 Z-0.09
 (Pass at FinishCut)
G0 X0.12
G1 Z-0.1181
G2 X0.12 Z-0.1819 I-0.0025 K-0.0319
G1 Z-0.198
G0 X0.14 Z-0.19
G0 X0.195
G0 Z-0.09
F1
 (Pass for Final Dimension)
G0 X0.116
G1 Z-0.12
G2 X0.116 Z-0.18 I-0.0005 K-0.03
G1 Z-0.2
G1 X0.175
G0 X0.3

I should add that my settings were X start 0.1750 Xend 0.1160 Filler Radius 0.0300 Z start -0.1000 Z end -0.2000 Z center -0.1500 clearance 0.0100 Finish pass cut 0.002.

Thanks

Vince

VINCE,
Didn't try your code, but i always look / dry run in MACH Turn . Find the bad line since manny times its just a XZ move and you need to just have one or the other first or as individual moves.
RICH

VINCE,
Didn't try your code, but i always look / dry run in MACH Turn . Find the bad line since manny times its just a XZ move and you need to just have one or the other first or as individual moves.
RICH

I guess I a little puzzled in that the code looked good in the preview window.  I thought Mach would cut what was shown.  I did do a dry run, but the movement is so small, only about .05" total in .002 steps and there are so many moves happening so fast, I could not tell it cut through the final arc.

Vince

Vince,
Don't be puzzled because after trying your settings in the wizard  and posting the code something is not right.
What is shown in the turn window seems to agree with the code, but, if you dry run it in MACH it is not following the pathing
and  you already know it will cut right through it. Just a short break at work so no time to fool around.
What version of Mach are you using?
RICH

MODIFIED:  SEE LATER REPLY

I have two different lathes, one running version 3.042.008 and the other 3.042.020.  Both versions do the same thing.

Vince

Have you got Mach set to Inc I&J's or Abs?

Graham

Vince,
I have not actualy cut the attached code file based on your posted wizard inputs.
The attached two files show screen prints of dry runs in Mach3 Turn.  1_ is for mach version
3.042.010 and the other is for 3.042.020. They are attached to show that there is no " cut thru the ball"
in Mach Turn simulation.

I forgot that, with a high rapid / feed rate, that the "simulation" in the newer version will not portray the pathing
correctly. Thus the pathing, when run, shows a cut thru the ball. As you know turn will be getting some attention in the near future.

Will actauly cut it this weekend. BTW the only mod i did to the file was changing the initial XZ move to x then z.

RICH
 

Have you got Mach set to Inc I&J's or Abs?

Graham

They are set for incremental.  I tried it both ways and got the same results.

Vince

As you know turn will be getting some attention in the near future.
RICH
 

So I was told by Brian in York, PA.  There is some really strange things going on in MachTurn besides this little problem.  I started going through my Smid book an studying up on turn G-code and found that MachTurn does very little of what is industry standard.  I also had a very strange problem on my CHNC.  I upgraded from version 3.042.008 to 3.042.020.  When I did my M6 tool change macro started working funny.  The turret would start indexing before it reached the tool change position and it no longer would see the turret index fault switch.  I changed back to version 3.042.008 and it started working again so something in the VB code processor got messed up in MachTurn 3.042.020.

I just spent 3 hours coding by hand a part for my Miser stirling engine.  It will be made out of steel and I am a little worried about Mach not doing what is displayed.  I wrote my code by trial and error, checking it in the Mach preview screen.  It will be cut with a 1/8" grooving tool.  I have attached it here.  If you could look at it and let me know if you think it will work I would appreciate it. 

Vince

Vince,
You were sitting right in back of me so we heard the same, but other than threading, i am not sure much has been done for turning, yet. I plan on playing around with my lathe this weekend. I finaly got it tweaked out but like you want confidence.

I am a pityfull novice code guy and just like you bought the Smid book.

Why the G53 in one of the code lines?

Attached is a DXF with some dim's ( for what it is worth ) and hopefully it represents your part, it dosn't have the curves in it.

Maybe i will turn a miniture one from your code just for kicks.

You ever consider fooling with Lazycam Turn or Lazyturn? Sure beats coding by hand!
RICH