I built a 5' x 10' plasma table using a Bulltear gantry kit and CandCNC BladeRunner controls back in 2012. Here is the build thread (https://www.cnczone.com/forums/bullt...al-rotary.html). It has mainly been used for prototype and limited production work. According to the Hypertherm display it only has 21 arc hours. Over the past year the cut quality has been slowly getting worse. There has been more dross and edge angularity then when it was new. It has gotten to the point where most parts are unusable. The nozzle and electrodes have been changed regularly. A refrigerated air dryer was added about 6 months ago without much change. I have even gone to pickled and oil sheets to avoid mill scale. Recently, all the torch end consumables were replaced including the cap, shield, swirl ring, and the cap O-ring with no improvement. Next, I contacted Hypertherm tech support to see if they had suggestions. Bob Churney, at Hypertherm, suggested it may be an issue with a lack of air pressure or a stuck pilot arc IGBT. I troubleshot both ideas without finding fault with either.

I just cut some parts from ¼” plate and there was a new strange cut. One edge of the part had a convex shape where the opposite edge had a concave shape.
With ¼” plate I used to get beautiful dross free cuts with no cleanup required now I get this or worse. I have played with torch height volts, both up and down, with no improvement. I have done the same with cut speeds with no improvement. Maybe related the torch height control has always had issues with thinner metals and finecut consumables. It will dive on larger cutouts. Any suggestions would be appreciated.
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