Z shift problems on 3.11 DHC

[Binderman01]

Hey guys I'm running a DHC with 3.11. When I'm setting z shift i normally get a 1.xx something, and then a message saying it was adjusted to 1 as -1-1 is max allowable. I'm trying to cut .25 plate and my pierce and cut is way to low and dragging the plate around. Hope you guys can help!

Luke

[Shane Warnick]

Is it possible your torch moved up in the holder just a little bit, and it's maxing out the downward travel on the Z axis (or real close)? Have you tried moving the torch down in the holder (closer to the plate) then re-zeroing the shift?

Shane

[Binderman01]

I wasn't getting full travel on my z from the rails being gunked up. However, now trying to cut the plate with a piece height of .14 it is dragging the plate once abs you can go back redo your z shift zero, and the next time with the same settings other than changing z shift zero it might be a .25" off the plate

[Shane Warnick]

Sounds like you are losing "steps" so to speak, on the Z axis, and it's not keeping up with where it's at. May be time for a new Z Axis motor, or the encoder that runs it could just be shot. Have you asked this question on the plasmacam website forum? If not I bet someone there can help, I am running a Samson with design edge, so I don't know exactly what you have and don't have. Or call tech support, they are there for a while longer today.

Shane

[PlasmaMac]

Check and make sure that your table is adequately grounded to a copper rod. There is some really good information on this in your video manual (you can get a replacement copy from plasmacam's tech team if it is lost). If some was wrong with your motor's encoder or anything else electrical, an error code accompanied by a descriptive message usually display within plasmacam's software program (even with the old school software). Many times improper grounding and incorrect arc-voltage shift or z shift values are to blame for erratic Z-axis behavior. Nevertheless, you can typically save an absolute ton of time by just dialing plasmacam's tech support and get an instant solution. They'll get you up and going a lot faster than attempting some of the trail and error tactics that gobble up too much time.

Good luck brother!

JAG

[Binderman01]

Thanks guys, I haven't had time to dig any deeper into it. I guess I need to relearn setting my arc voltage shift, and work on grounding it better and go from there. The weird part is it cut thinner stuff well beyond my expectations even with my z axis being messed up and me not noticing.

[PlasmaMac]

Good luck brother! You'll get it licked in no time. Make sure to call plasmacam's tech service. They have never failed to help me out when I needed it. I have also learned a by using the video manual that came with the machine. Sometimes, I completely forget how do things that I have not done in a while and plasmcam's video manual, i come to find, pretty much has a reference to anything you'll most likely encounter with the system.

JAG

[Binderman01]

Will arc voltage shift effect it with the torch off doing a dry run? What is arc voltage shift even for? I understand on the newer models with the ohmic ability, which would be great, unfortunately I don't have that capability

[1MORECUT]

No,The arc voltage shift is for setting your cut height ,If your cut height is low you will rise the arc voltage shift and if it is high you will lower it.
Hope this helps you.

John

[jimcolt]

On a Plasmacam you do not set a voltage for height. The older model DHC requires that you set a voltage shift.....which compensates for the location of the torch. The newer models with ohmic sense auto calibrate the THC before each cut.

Jim Colt Hypertherm

[Binderman01]

Thats how I thought it was. I'm not to sure my issue isn't partially in my z axis rails. It almost acts like it comes down to stall on material and thinks it hits the metal when it hits a rough spot in the rails. I changed my stall setting up to .1 and its doing better. I still get inconsistent heights between initializing and doing dry runs. One time it will drag the next it's a .5" up. Initialize it a third time and it might be spot on. But we are definately getting there. Cut some pretty clean pieces after messing with it awhile.

Jim what do you recommend a base starting range for voltage shift on a pmax 45 with standard shielded consumables?

[jimcolt]

I have a DHC2 that uses ohmic.....never in 9 years of use have I had to set either voltage shift or z shift...as the ohmic does that before each cut. Best bet for that info is to speak with George at Plasmacam tech support. Even better, join the owners community on the www.plasmacam.com website (have your DHC serial number handy). I think there is a procedural writeup available on that site, if not there is plenty of quick help!

You may be correct on the z axis. I would suggest disaddembly and cleaning so it opeates freely. That axis is a stepper motor...and it can easily stall and lose position if things are not smooth and clean.


Jim Colt Hypertherm

[murrfin]

Jim, Iam new to Plasmacam, I have DHC controller,having trouble with pierce height and cit height.I set pierce height as per plasmacam height control setup. set pierce height @ .100, intialized, jogged tip to touch material, zeroed and ran cut, tip higher than .100. Arc shift @1. how do I set pierce height manually to .100 above material?? my tip is touching material during cutting, going thru lots of consumables. Hope you can help.My email murrfin@gmail.com