Hypertherm 65 / Proma SD / Fine cut

[kwikway]

Hello Everyone,

I am having some trouble getting my plasma table to cut properly. I am running a Hypertherm 65 with a Proma SD THC and I am using fine cut consumables. My biggest issue right now is setting up the THC so it doesn't move too far away from the metal while cutting or move too close and shut off the arch.

These are the settings I am currently using:
speed:80
voltage: 55v
delay: 2.0

I do not know how to make sure the height is correct for the fine cut consumables. Any advice would be greatly appreciates.

[tcaudle]

You start by making a cut at the right height and feedrates and getting a voltage baseline reading with the DTHC disabled. On a THC that displays actual Torch VOlts while it cuts that becomes pretty easy. Fine cuts are a challenge even with a more sophisticated THC.

[acourtjester]

When you do as Tom states be sure to make a straight cut at the correct height long enough for the volts to stabilize then read the volts on the Proma display. This will be your voltage for that thickness of metal, the speed posted in the 65 manual will help for each metal thickness too.

[kwikway]

Hello guys.

unfortunately. the Proma SD is not controlled by the computer. its connected between the control box and the Z motor. So once the plasma turns on it starts doing its thing.

[acourtjester]

Ok the Proma units I used supplied signals to the computer, Arc ok, Up, and Down through the BOB board's input pins.
It sounds like you have a different setup, maybe someone else here can help you.
You might list what table and electronics you are using.

[tcaudle]

According to the voluminous 6 page manual there is no way to turn it off , disable it or bypass it.
So you can't cut with the THC disabled and have it display the actual cut voltage.

[Steambike]

I have a Proma as well, and mine is also tied into my computer BOB, But (just thinking out loud) if you set the z axis where you want it height wise and then disconnect the up and down wires from the screw terminals on the Proma ( or the common wire), the Proma is essentially a pair of relays, 1 common wire and then connects to either up or down based on settings you put in......(that's assuming you can access them, mine are on the front face) then your height will remain steady for a test and you should be able to read your voltage at that current and height..... the only bad thing is you can't move after pierce.
If you wanted to go a little fancier you could put a temporary switch in the common wire (very temporarily) let it pierce and then go to cut height and then "cut" (switch off) the common wire so no more motion...then you can read your voltage from the Proma face...just my 10cents, I'm going to be starting the same process over again with my new 45xp in the next few days....
Be aware though, I do not know what voltage you are switching there, mine is 24vdc, but yours could be mains power or????
Good luck!

[kwikway]

Hello guys,

Today was a good day. I got the Fine cut to work after a lot of trail and error. I got it to work with the following settings:

Proma Settings:
47 Volts
Speed 125
Delay 5.0

Hypertherm [Sheetcam] Settings:
45A
3700 mm/min
Pierce Delay: 0.4

Note: I am using the Low Speed Fine Cut Mild Steel Settings.

It is not perfect but it cut. I have posted some pictures of my last cut of the day [See attachments].This was cut on hot roll. I'd appreciate any ideas on what to do to remove the dross on the bottom or any other tips on improving cut quality.

Thanks All!