Poor cut quality Need Help

[libertytayler]

Hi all new here to the forum. I am using a Hypertherm Max200 on an C&G systems Mustang Table.
I have some really pressing issues that I am not able to figure out. No matter what I cut from .250 to .375, i always end up with a large bevel angle on my parts. I am running it at 200 amps to cut the .375 (mild steel) and it cuts decent with barely any dross at 100 ipm, but the bevel angle on the parts is too much. My welders are having problems fitting. I have done some test etc. and slowed my speed down to 50 with considerable results, with little dross, (slow dross). I thought i might be having issues with the nitrogen (shield), but I"m not sure now. Hypertherm gave me some test to do and all have turned out good that it's not the arc or the unit. "They seem to think it might be in the drive motors. When the pierce starts, looks good on the first edge of the part, but as you go around the part, the bevel angle gets worse, (not consistent) Any Ideas Anyone.. ? much appreciated for any help. I have tried cutting .250 at 100 amps but have to slow my speed down, but i end up with more dross. I'm out of ideas.

[jimcolt]

I need more information. What gases are you using for plasma gas and shield? Can you tell me at what speeds, amperages and arc voltage are you cutting on the .250 " and .375"?

I have worked with the Max200 since it was designed over 20 years ago...be happy to help you get it dialed in.

Jim Colt Hypertherm

[libertytayler]

Thanks. I am running on .250 at around 120 to 160 on 200 amp. and on .375 200 amp around 100
Arc voltage on .250 is 120 and 125 on .375.
Using O2 for plasma and N2 for shield.

I did a test cur for a part that I needed cut on 2" at 4 ipm with about the same bevel angle as the .250 and .375.

Some inconsistency somewhere but not sure where to start.
Thanks. Will be happy to provide more information if needed.

[jimcolt]

200 amps is too much power to get a square edge on .250 or even .375" steel. With plasma...for best cut quality you must match the power level to the material being cut...too much power and you can cut very fast, but with more edge bevel, and poor fine feature quality.

The Max200 has some very well developed cut processes.....and the cut charts in the manual are right on as far as specifications go for cut speed, arc voltage, cut height, and plasma and shield settings.

I recommend using the 100 amp oxygen consumables (make sure they are Hypertherm brand...the aftermarket parts produced by a variety of other companies are different). Follow the cut charts exactly...set all parameters exactly as the Hypertherm manual suggests...and you wiull get nice cuts on the steel you are cutting.

And...you should be using oxygen as the plasma gas with air as the shield gas. If you are using Nitrogen...expect poorer cut quaity and more dross.

Jim Colt

Thanks. I am running on .250 at around 120 to 160 on 200 amp. and on .375 200 amp around 100
Arc voltage on .250 is 120 and 125 on .375.
Using O2 for plasma and N2 for shield.

I did a test cur for a part that I needed cut on 2" at 4 ipm with about the same bevel angle as the .250 and .375.

Some inconsistency somewhere but not sure where to start.
Thanks. Will be happy to provide more information if needed.

[libertytayler]

Thanks Jim.. Getting my boss to c the difference is like going thru a brick wall. I tried explainging a lot of different variales that the Hyperthem techs explained to me and he just seems to ignore them. He thinks nitrogen is better to cut with, as well as we dont have a dryer on the nitrogen line so we could be getting moisture in theline with this high humidity here, as well as not running 1\2" line from the nitrogen tank to the machine. We are using 3\8" line currently, which hypertherm tech said we need 1\2" to get enough volume of nitrogen for the shield. He thinks that you can turn the pressure up to get more volume. doesn't work like that. I know that . but getting all of this to him is a different story..


thanks Again..

I will c if i can't get him to use the air instead and c what the cut quality difference is..