Loosing ArcOK?

[Mr.Hotwire]

Good day,

So, I have a machine setup and its cutting. Kind of... I have a few issues, but Im working on one at a time so.. first one.. the THC...

I have a UCCNC AXBB-E machine setup using a MiniTHC. Im testing the inital settings by trying to cut 20g mild steel. When I try to cut with the THC on, It pierces, gets ArcOK for a split second but looses it, the Arc stays lit for 2 seconds then goes out. There is no further movement.

Im cutting 20g mild steel, using 35a and 45psi. What are the chances that Im looking ArcOK, and the MiniTHC sees that and prevents the rest of the cut from happening?

[robertspark]

have you set the thc delay in the mini thc correctly?

what settings do you have within the minithc and what settings do you have on the uccnc thc screen set

[TJS]

What Plasma machine. 45psi seems kind of low.

[Mr.Hotwire]

Its PrimeWeld Cut 60.

Delay in MiniTHC is set to 0.

[jmersereau]

The PrimeWeld Cut60 only needs: Air Pressure: 40-75 PSI and Airflow Required: 5 CFM @ 80 PSI.

Not saying a higher air pressure won't improve the cut quality but the min to operate is low.

My suggestion is turn the amps down and see what happens, is it possible that at 35A you are blowing too large of a hole? Try 25A. I cut 18g at 28A with my Cut60.

Have you got really dry air and have you inspected the electrode to see if it looks scorched or damaged?
-
Jim

[Mr.Hotwire]

Iv got 2 air dryers inline, a separator and 2 disposable filters.

The pressure I thought was low too, but that is what the manual called for. The amperage as well. I will drop both to your suggestion of 28a and 40psi. One at a time of course, changing everything at once doesn't narrow anything down.

My kerfs at my current settings is TINY! like 1.2mm.

[robertspark]

Its PrimeWeld Cut 60.

Delay in MiniTHC is set to 0.

increase the delay to 2 sec and try again.

[jmersereau]

My kerfs at my current settings is TINY! like 1.2mm.

That is the right size kerf for those amps, 1.2mm = 0.04" which is what I am getting.

Did you check your electrode and cup for damage or a black scorched swirl?
Jim

[jmersereau]

Also what are you using for pierce height, plunge rate and cut height? I am running pierce delay=0.5s, pierce height=0.15", plunge rate=60ipm and cut height=0.06". I run at 110 ipm cut speed on 18g

[Mr.Hotwire]

My pierce delay, as set in UCCNC was 0, Since I moved that upto 700ms I have been getting completed cuts with THC turned off. Pierce height is 3.8mm, cut height is 1.5mm and I am cutting at 3600mm/min. All of these are fairly close to your settings.