Hi all,
I'm working with an EZRouter that has a Thermal Dynamics Cutmaster 151 plasma cutter. It has a floating torch head. I think thats what it is called. The torch head is about a foot long and mounts to the z axis.

The problem is getting consistent cuts.
Here is how a cut goes most of the time.
Settings from the book start at 1/4 inch steel and just go thicker. There are no settings for anything less than 1/4 inch.

3/16 carbon steel.
Volts: 104
Amps: 100
Pierce: .190
Standoff: .150 (I'm assuming this is cut height)
Cutting speed is 70 in the book. I'm not 100% sure on this because I don't have the book in front of me.
THC is on.
Consumables are for 100 amp

I hit the run button and the torch will move to the first pierce point. The torch will move down, find the plate, move up to .190 and come on. It will pierce and then drop to .150. The THC does its thing at this point and I can see the torch height moving quite a bit in the DRO read out in Mach3. The THC-1000 control volts will fluctuate greatly on the THC readout. Eventually the readings all settle down. The DRO readout for the z axis might stabilize at .232, a large difference between what is programmed and what happens during the cutting.
While the cut is going on, about 1/2 the time the cut will be going smooth and suddenly the torch stops cutting through the plate. It will make an ugly scar in the plate and not pierce completely. It isn't consistent either. I can cut the same part 3 times in a row and won't mess up at the spot. It will mess up in other spots. 70 is way too fast to cut 3/16. I need to slow the speed to about 40 and then the torch will cut through 90% of the time but the slag on the back of the plate is horrible.
Any thoughts or suggestions are appreciated.