G code with a bar puller

[Vern Smith]

I set up my bar puller last night and the physical aspects went well but the G code did not go well at all. The lathe is a week old so I know nothing about it. I can not get it to respond to any G code commands with the spindle unclamped. I looked through the settings and could not find anything to do with this situation except the option to disable the foot pedal. I was able to get the program to run through the M11 and unclamp the collet but that's where she locked up.

I would appreciate it if someone could give some suggestions on the sequence of events or movements they use to pull a bar and maybe include the G code they are using to accomplish it. I did notice that sometimes my collet would spit the bar forward when it unclamped. I would think this could complicate the pulling operation. Do you position a tool in front of the bar to limit the amount the collet can spit the bar?

This has to be a lot simpler then I'm making it.

I found the information on this forum to keep my spindle from starting and stopping with every tool change, that was a major improvement in its self, it sure is great to have forums and responders to point these things out to us amateurs.

I'm still looking for the number of the parameter that determines the amount of time the air flows through the spindle after it shuts off. Mine runs 5 minutes after shut off which seems to me and my compressor to be a little excessive.

[Geof]

You should be able to do rapid moves with the spindle unclamped but you cannot do feed moves in IPR. Before opening the chuck do a G98 command and you should then be able to program a feed move in inches per minute to pull the bar; then when the chuck is clamped again command G99 to go back to IPR.

You will not be able to Single Block through the pulling sequence. Put a M00 after the chuck is clamped, turn off Single Block just before you reach the unclamp command and then turn it back on at the M00 stop.

[Geof]

I reread your post.

The pulling sequence, in words is:

All this should be in a subroutine.

Position puller near part. (turn off Single Block here)
Stop spindle.
M98
Feed puller forward in inch per minute to engage puller with part.
Open chuck.
Pull part out to required position using feed in inch per minute.
Close chuck.
Feed puller away from part.
M00 (for turning Single Block back on).
G99 (Reinstate IPR)
M99 (Return from puller subroutine and continue program.)

[Vern Smith]

Thanks Geof, got it all working now. Some of my problem was trying to single block through the sequence.

Vern