Another plasma component...

Stefan, Its possible that you have not got your velocity and acceleration configured right for plasma and external offsets. To understand this, picture a lathe with an external offset being applied by a mathematical formula to machine a lobe on a cam. So the lathe is blindly spinning around with the cut diameter set to a fixed diameter and the external offset moves the tool in and out to machine the cam. So we need to allocate some portion of the axis velocity and acceleration to external offsets or the tool can't move. Thats where the ini variable OFFSET_AV_RATIO comes in. Say we decide we need to allocate 20% of the vel and accel to the external offset. We set this equal to 0.2. The consequence of this is that your rmaximum vel and accel is only 80% of what it could be.

So with plasma we do a trick and we can only do this becasue the THC and jogging of the Z axis are 100% mutually exclusive.
What I worked out before the external offsets was released we could double our ini file settings for vel and accel and apply
OFFSET_AV_RATIO = 0.5
That way the maximum vel and accel will be available for both probing and THC.

So Its possible you have got the ratio set to 0.5 but have not doubled your VEL and Accel.
After much testing and cursing over missed steps I have my 2 x vel and accel numbers for a NEMA 23 stepper set at 120 and 1400 (which is really 60 and 700)

Thanks for your help guys,

As what Rod posted I had both sets of Velocity and Acceleration set to the same number, I did not read the ini closely enough and did not realize I needed to double the first set of numbers.

It cutting much faster, I just need to set up the THC off before the end of cut in sheetcam because the torch is diving at the end of cut and tripping the probe limit switch.

Ok another problem for Phill,

I am having difficulty with the Ohmic sensor, When I cut out a large slot or hole the water that is sprayed up after the end of cut when the center falls away is causing the ohmic probe to trip on the next probe event,

I do not see much way around this, as this only occurs on certain parts ,is there a way we could place a Ohmic Enable or Disable box in the plasma config page? That way we could turn it off when we know we will be doing parts that will spray water up and rely on the probe limit switch to detect the surface height.

Ohmic enable/disable could certainly be done.

It would be interesting to hear if others are having that issue as well.

How about one of:
1: Increase the post flow time so that the air may blow the water away.
2: Pulse the torch on at probe start to get some airflow to blow the water away.

phillc54 wrote: Ohmic enable/disable could certainly be done.

It would be interesting to hear if others are having that issue as well.

How about one of:
1: Increase the post flow time so that the air may blow the water away.
2: Pulse the torch on at probe start to get some airflow to blow the water away.

I would like to try the second option as I feel the first will increase cycle times,

Also just having the option in the option in the software to manually disable the Ohmic probe and revert to the probe limit switch would be a very handy feature, I know its not a good idea to just keep adding features after features but I see a real common sense usage for that particular feature.

Increasing the post flow time shouldn't increase the cycle time should it, or does that impact on when you can fire the torch.

If we added option 2 then we would also probably need to be able to enable/disable that as well.