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High Definition Plasma cutting?

Hi everyone, I am in the front office (Inside Sales) of a fairly large fabrication shop. We are in the set up phase and are set up with equipment to do 1/4" and under as well as stainless steel, hot rolled, cold rolled and aluminum. We also do quite a bit of sheet metal work with galvanized in various gauge sizes. We have a plasma table (I believe they call it a high definition? It seems to cut the black and stainless fairly well but the galvanized material is giving us grief....especially in the smaller sizes... 18, 20-26 ga the tip seems to dive into the material frequently and causes much down time and lots of frustration for the operator. (He is fairly new at this...we all are. nobody seems to be able to tell us what to try or what might be causing this. Some phone calls placed to the fellow who was supposed to know turns into.... more amperage...or less amperage....check your ground... We have found that putting the ground clamp directly on one corner of the sheet we are cutting seemed to help but it is not the solution. (we were changing our tip frequently) Any Ideas or experienced wisdom on anyone's part would be greatly appreciated.

Darcy Ritchie
- Saskatoon, Saskatchewan. Canada
2000

It sounds like your AHC Automatic Height Control is out of adjustment or not working. We had similar problems. Since it is new, I would call in their field tech to resolve this. If the voltage is set too low by the operator, the response time may not be quick enough to follow contours from distortion etc. This is a setting the field tech should be able to correct.

Bradford P. Maas
- Northfield, Minnesota
2000

well I been operating a high definition table for a few years but have not cut much light ga material/ but I cut light ga material in manual most of the time

irving Bennett
- Ontario Canada
2001

In my shop this problem usually goes away if you speed up the cut speed or increase the arc voltage. Usually you are cutting so slow that the material is burning away in front of the plasma arc so the torch head control starts to lower in order to find the material. We cut 26 ga. galv. all the time with out any problems.

Matthew McDermitt
- Denver, Colorado
2003

I have found that actually grounding the table itself with a earth ground has helped us in cutting galvanized. We just drilled a hole and attached a two foot steel rod with a good connecting cable right to the slats and it worked great for us.

Chase Sebastian
- Mesa, Arizona
2004

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I am looking to purchase a CNC plasma table & want to know the difference (purchase cost, consumable cost, cutting tolerances, cutting quality & construction differences) of conventional plasma cutters verses high definition plasma cutters. I would appreciate any information anyone could give me. Thank you so much.

Sincerely,

Leo Metz
stainless fabrication - South Elgin, Illinois
2007

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Ed. note: Please confine any replies to generic and technical issues rather than recommending specific suppliers. Thanks :-)

Torchmate has a decent article at www.torchmate.com/cuts.htm. I would suggest that you talk to your local consumables supplier (gas, tips, wire), someone like National Welders. They should be able to look at your shop and your application to provide you some quality direction. They should be able to take you to other shops and provide quotes on equipment. This will be a relationship that includes training and support.

Tracy Beach
- Greensboro, North Carolina
2007

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Dear,

We are a supplier of plasma tables

The problem is your height control. I think the cutting voltage you use is wrong. So you have to try with a higher voltage so the torch is going higher. Normally your machine has to measure the voltage automatically, but a lot of machines use the fixed voltage, you put in in the parameters.
Galvanized steel normally gives a very good cutting result.
Try to get the speed as high as possible.
Possible are the PID settings of your height control not good.

Levrouw Joost
- lichtervelde Belgium
May 13, 2010