DECELSTOP

[toolmanwaz]

Is it possible to ues DECELSTOP command in G02/G03 logic? I already have it issued in the G00 and G01 logic, but what I am seeing on our Lucas boring mill is there is a slight pause as the machine goes from linear (G01) to The circular movement (G03) but when it goes from circular (G03) to linear (G01) code, the slight pause is almost non-existant. Currently, I do not have any DECELSTOP command in the circular files. When you machine from linear to linear, I do not see any hesitation at all; however we are not machining at a very fast feed rate on those tools. When we are yusin the high speed spindle, we are running 7,500 RPM at @ 40.IPM. Not super fast, but I would still like to get rid of that nasty nono second pause. Thanks

[Carlo Rechi]

Try to set BLEND=-200 in your CNC SETUP

[toolmanwaz]

Hey thanks Carlo;but blend has no effect on the results. If you set it too high, it will actually start lines of information too soon. I should clarify that this is a large boring mill the rapid speed is only 150 ipm. Tuning it was a nightmare.

[Karl_T]

I'd be tempted to remove the DECELSTOP from your linear G01 and see what happens. DECELSTOP causes a slight delay. Are you aware that the DECELSTOP command effects the next move? That it, you say DECELSTOP:GO x,y to stop after the x,y move. (This one got me once)

There a ton in "search for solutions" about getting rid of hestitations. Read up on it.

Karl

[toolmanwaz]

Karl,
I did try that once. The machine will come to a screeching halt at the end of each linear move,pause for a fraction of a second then continue. I think it is best to have the DECELSTOP in the G01 file on the X ,Y,and W axis. The Z axis may not need it as there is not much inertia to overcome. I guess my question is can you put DECELSTOP in the G02/G03 logic?

[camsoft]

Hello Gentleman,

It may be best to look at the reason the machine pauses going into this arc. Since it is a heavy machine the inertia of weight maybe over or undershooting the set tolerance and then waiting until the tolerance is satisfied to move on. The only other reason is that the PC is busy or the CPU running slow at the time. Before you increase Tolerance we want to explain the suggestions given thus far.

As for the Blend & DECELSTOP solutions you're actually all correct.

It's easy enough to see if any carry over from DECELSTOP has an affect on the next arc move by commenting out the DECELSTOP logic commands in G0 & G1 temporarily.

As you mentioned in the last post. Yes it is legal to place a DECELSTOP in the the G2 & G3 just above the CW & CCW commands.

A minus Blend value will initiate the arc command Nth milliseconds early and does cause the G code display and Graphical Tool Animation to be begin sooner. It is the Tolerance value that ensures that the physical move is at the right position. By keeping Tolerance the same you may start with a minus BLEND value of -50 or -100 or -150 and this will still hold Tolerance accuracy plus satisfy the system that the next move is ready to go by means of time and/or position both.

Tech Support
CamSoft Corp.
support@camsoftcorp.com
PH 951-674-8100
Fax 951-674-3110
www.cnccontrols.com

[toolmanwaz]

Hello all and thank you for your timely responses.
What exactly should I see if I comment out the DECELSTOP in the G00 and G01 logic? Right now, the BLEND is set at -60. This seems to give a favorable response to all of the linear moves. If you incerase this value, the machine seems to actually increase the accel speed for a split second as it enters the newly commanded move. Since we are running a high speed spindle, you can actually hear the change in pitch. The pause I refer to can only be seen at the beginning of the arc; none at the end. There is a seemless transition from the arc to the linear motion. Unfortunately, it is something we don't want to fool with until the job is finished as we are behind schedule. I will have the program in memory however then I can play with the parameters.

[toolmanwaz]

Can anyone explain how RAPIDSPEED command works? I can only make it work in the logic files if I specify each axis.
RAPIDSPEED 1;160000:RAPIDSPEED 2;160000:RAPIDSPEED 3;160000
RAPIDSPEED 4;160000
I cannot say RAPIDSPEED 160000 ;it will remain at the former rapid speed

[Karl_T]

I've only used the RAPIDSPEED <axis#>;speed syntax. I see in the help on RAPIDSPEED they mention RAPIDSPEED without an axis specification. I don't see how this could work and i suspect a slight snafu in the doumentation here.

Anyway just use the RAPIDSPEED <axis#> ; speed syntax and you won't have any trouble.

karl

[toolmanwaz]

Thanks Karl Thats what I what I was finding, but I thought there was something I was doing wrong.

[toolmanwaz]

Removing the DECELSTOP command in the G01 code did solve the hesitation problem. I also bumped the BLEND command from -60 to -100ms as suggested and that also seemed to have a positive effect on the machine. Increasing it above -100 (went to -300) had no visual effect so I left it at -100. The machine seems to respond well without the DECELSTOP command but I wonder why it is recomended in the G01 file.