[empirecustoms]

i have a 1650 hyper therm using 80 consumbles and running 75 psi of air at 80 amps cutting 3/16 4 x 10 sheet mild steel on mach 3 on a ez router table.. going 39 ipm beacuse of poor cut quality i have talked to hyper them and the say i might have a bad piolt arc igbm board i belive. but the service man said it was fine .. so i am at a loss the cut quality looksd like is being rushed the hyper therm book say i should be able to run 140 i belive not in front of me right now.

[quisman]

Empire, Most often...if the pilot arc igbt fails it will not pilot arc at all or it will continuously pass pilot current even after transfer has initiated, and you will find your nozzle to have a "notch" in the orifice and your cut quality and consumable life will diminish, but I would expect nothing like you are seeing. I am not surprised your machine passed the service test.
My 3 main concerns are, Power output, air quality/pressure, and THC settings.
I would expect with too much amperage, you would be able to cut w/ optimum speeds no problem but experience poor cut quality and consumable life. Air pressure may show a perfect possibility of your problem here. Perhaps you have enough pressure built up at the pressure sensor but have a restriction in the torch lead or after the pressure switch and in between the torch lead. This would allow the G3 to be satisfied yet yield very little output which will result in the inability to cool the consumables properly. It will also allow you cutting material to come back up into the shield and nozzle due to the lack of shield gas blowing the material away.
Next is the Torch Height Control. I recommend raising your pierce height to a level of approximately 1/4 of a inch and see if you can still pilot arc to the 3/16" plate. If you are piercing to close you may not be able to effectively use the shield to "blow" the material away and result in the slag arcing inside the consumables.

Check that air pressure at the torch head while in gas test mode.
Get your hands on a DC Current clamp meter if possible and check your cut current on the work lead.
Set you THC to manual mode and see what you can do for piercing options.

I recommend using the 60 amp process for the 3/16" A-36 material. It is slower but will yield amazing results when your system is back up to par.

Let us know what you find and good luck.

[quisman]

Mark, any luck from this beauty

[Med-Pac]

I think part of your problem may be with your air pressure. We have a 1000 hyper, for 7ga mat'l we use 60 amp consumables with 80+ lbs of air pressure. I say 80+ because the gauge reads 80 at max., but the indicator light does go past the 80 a liitle bit. Our setings are; voltage-155 to 160ish, 65-70 ipm. With your 1650 100-130 ipm should be attainable.

We have run into a few issues with moisture control, but those problems become very obvious and easy to diagnos. We put in several filters and an inline dryer to save on our consumable life.

I would also recommend you send Jim Colt an email. He is here on CNC zone, he's a hypertherm guy. I don't think he'd mind helping you out, he's helped us with a few issues in the past.

Hope this helps ya
Mike

[empirecustoms]

yeah so far so good.. i am stil havin slow cut times but i have added a another in line seperator to the back of the machine and am going to try 40 amp consumables .. i was down last week the hypertherm repair guy changed out the piolt arc igbt boarded .. so i am crossing my fingers that i will finaly get some cut time and see where i am . the bigest problem i am seeing is the over heating of the electrode

[empirecustoms]

so it all fixed now and back up and runnin. i got the speeds up to 50 and looks good so far having some seroius problems with the hole quality now all the holes are oblong and just choppy. cleaned the table and gears really good and double checked the balcklash on all the axis. seemesd to help with a hole that was 1-51/64 .. now the problem i am having is my holes layer doesnt seem to work with the thc.. what i mean is the tourch does a touch off and goes to the cut height and then ramps into the material and snags the materail a bit and woobles the hole for lack of a better term. i have changed the cut height to .15 and pierce height to .25 and the arch voltage set at 147 like the books says any ideals how to fix this ? and the hole size is .50

[Gillyshank]

The problem is probably with the torch height disable setting on your controller.

When going round a small diameter the machine does not usually get upto full speed - therefore burns away more material causing the torch to dive.

Your controller should have a parameter to freeze the height sense until it gets upto speed. in some cases the height sense is not turned on at all on very small diameters.

the height sense is also frozen on corners