help with cutting a inverse taper angle

[redfoxbody11]

Hey all I have a question. I would like to know if there are any canned cycles I could use for turning a inverse taper angle for ex. / as opposed to a reg. \ angle. If I try to use a g71 turning canned cycle it tries to cut the stock in one pass. My boss says that aside from point to point programing its not possible. Is this true? Is there no canned cycle able to work for this application?

[MILLMARK]

Give this a try. On the first N line of your G71 cycle, put a Z on the same line with your X move. I think it can be the same as the Z position that defines stock size before the G71, so it isn't really a XZ move at all. This simply tells the control that there is undercutting involved. Sorry if I'm not being too clear. Let me know if you get it working. Good luck

[redfoxbody11]

I tried adding a z on the first n line in the g71 cycle. The machine kept alarming out once added. I tried various z values as well all resulting with the same alarm. (alarm 065 illegal command in g71-g73)

[redfoxbody11]

Here's the current trial program I wrote rq to test your reply.

N1
G40
G28 U0
G0 T0101
G50 S1500
G96 S400 M3
G0 X5.1 Z0.05 M8
G71 U0.075 R0.01
G71 P101 Q102 U0.01 F0.008
N101 G0 X4. 98 <-- I added the z here but it alarmed
G01 G42 Z0.0
G03 X5.0 Z-0.01 R0.01
G01 Z-0.125
X4.0 Z-4.0
X5.1
N102 G0 G40 Z0.05
X10.0 Z10.0
G28 U0
M0

[MILLMARK]

Looks like you did it right. That format works on our Haas machines. Sorry I couldn't help. There's gotta be a way, that's a pretty common operation

[redfoxbody11]

The machine I was using with that program was a super kia turn 28. Tried with a hitachi seiki 4ne as well same result.

[MILLMARK]

Ok. I tried your program, and I also got an alarm. I took the Z off of line N102, and it ran. If this doesn't work, I'm out of suggestions

[redfoxbody11]

Removing the Z on the quit line and from the start line allows the machine to run the program but it cuts the angle in one pass ignoring the depth of cut given. Taking over 4 inches of material would not end so pretty =P.... I'm back at square one again as that is what my program was doing to begin with. Thank you for your time =D

[MILLMARK]

On my machine it takes multiple cuts (.075 each). Not sure what the difference could be.
Here is exactly how I wrote it:

G00 T505;
G50 S1000;
G97 S500 M03;
G54 X4.98 Z.05;
G96 S500;
G71 U.075 R.01;
G71 P101 Q102 U.01 F.01;
N101 G00 X4.98 Z.05;
G01 G42 Z0.;
G03 X5. Z-.01 R.01;
G01 Z-.125;
X4. Z-4.;
X 5.1;
N102 G40;
G00 X7. Z5.;
M30;

I don't think this is a Haas exclusive feature, can't see why it ain't working

[redfoxbody11]

I copy and pasted your program with the exception of using the g54 as this machine cannot use it instead I used a G00 . Still getting the same alarm. The machine dose not want to hear a Z on the pick up line. Perhaps my company cheaped out on a key parameter... other then that I can't see why it won't work for my machine but it will on yours.

[redfoxbody11]

Also out of curiosity why do u use a g97 s500 m3 then change to the G96 after you call up the starting x and z position? I was always told to put the g96 in before I give the starting x and z position and not using a g97 at first.

[Algirdas]

why do u use a g97 s500 m3 then change to the G96 after you call up the starting x and z position?
no need for constant cutting speed while not cutting. It's proper - spindle revolution speed is constant when approaching from tool change position. Othervise revolution varies and axes are waiting till spindle speed stabilize.