Pierce delay needs to be long on 1st cut but short on all other

I got my table up and running over a week ago and cut 3-4 big signs every night after work. Everything is great except I need to fine tune my pierce delay. I have a thermal dynamics cut master 42, I had to set the pierce delay at 2 seconds so the torch would fire in time to start making the first cut because the machine has a huge delay on the first time it fires. Just like normal handheld operation, once its fired the first time, its stops firing to move and start the second cut (and every fire after) it has a half second delay before it fire but the post process being at 2 seconds makes the torch just sit there and fire for another second and a half before it starts moving. If I lower the pierce delay any shorter, the torch won’t fire in time before the torch starts to move for the first cut. Is there anything I can adjust on the post process or my machine itself to allow time for the first cut to be 2 second delay but every one after a half a second? thanks for any info, btw I love this machine!

What gauge are you cutting?

Sounds like you may need to check your consumables, specifically the start cartridge.

14 gauge carbon steel

Never changed my start cartridge and it busted this weekend… lol picking one up today

Problem solved! Lol hopefully

Put all new consumables including start cartridge, still nothing. I borrowed a buddies torch and it cut like crap for about 5 minutes then would just scratch the metal and not cut all the way through. TE cutmaster 42 had a 4 year warranty on the unit but only one year on the torch. I ordered a new $350 torch and if it doesn’t fix it I’m sending machine off for repair. Going to borrow a hypertherm until then.

Check the ground? The lug on it , dinse etc. do an ohm test on it to see how high the resistance is

unfortunately I got rid of my cutmaster82 for the same reason. It has the same variable start of 1-3 seconds. Ended up selling it and getting a Razorcut45 which is a hell of a down grade. The RC45 does work, but sucks compared to the cut quality of the Cutmaster. Going to eventually purchase a hypertherm.

I’m having similar problems with my TD cutskill 35. Pierce delay is highly variable. I think it’s a mach3/gcode thing…

For example,

If I set 1.0s in the .tap file, it will start just fine on the first cut. On the second cut, however, it can fire and sit on the spot for 2-3 seconds before it moves off and sometimes the torch will flame out (perhaps it burns through the metal or perhaps fails to fire after the starter arc stops)?

I have tried manually changing the delay for each cut within my .tap file but if I lower it on the second one, it the toe h holder can actually start moving off before the torch even fires.

I think there some kind of additional delay/settings (perhaps in the torch)?

I’ll try and get some video to post somehow - because even if I run the same torch delay for a series of cuts within the one cut file, I get different actual delays between when the torch fires and when the gantry starts moving.

I am having the same issue with my Everlast PowerPlus 80s. Did you find a way to fix the issue ?

Hi.

The answer is yes and no… I have been able to get it to work consistently it still not sure if there are intermittent delays.

I set up my cut files (.tap) so that the initia delay is 1 second and every subsequent delay is either 0.8 or 0.9 and that seems to make it work. If for any reason I need to stop/restart, I find that 0.8-0.9 seconds is too short when the plasma cutter does not already have post flow going. Therefore if you have a long pause of any type in your cut program, I’d recommend putting in a pierce delay of 1 second again. (Sometimes I have to pause to let me compressor catch up)

I presume you are aware of the gcode syntax where g4 is the pierce delay, followed by px.x where x is the pierce delay in seconds?

So for me, a cut program might look (crudely) like this

File ##

Cut #1
M3 (torch fire)
G4 p1.0

Blah, blah

M5 (torch stop)

Cut #2
M3
G4 p0.8

…
…

M5

Cut #3
M3
G4 p0.8

…

M5

G4 p120 (long pause - refill compressor)

Cut #4
M3
G4 p 1.0s (back to the initial pierce delay as the post flow has on the plasma cutter would have stopped)

…

M5

End

Hope this helps
As I said - I think it’s to do with the post flow of my plasma cutter - any time the air is still blowing through that nozzle you have a shorter pierce delay. Oh and this info works for me on 3mm steel. I can’t speak to its usefulness on heavier or lighter gauge stuff as I haven’t tested it.

Lastly, make sure you have a good earth (i clamp directly to the stew sheet you are cutting). I’ve found that clamping to the cutting slats can be a bit flaky.

Hope this helps - if I can assist with your troubleshooting at all let me know.

Regards,

Paul

Just found some additional info on this topic on this forum. Head on over to here:

move off of zero, manually fire (toggle on and off) the torch then return to zero. start the program and it with cut normal.

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Just to clarify, most of the air plasma systems (all brands) use blowback start technology today. (blowback was invented and patented by Hypertherm in the mid 1980’s by the way, the patents have expired…so anything not Hypertherm can use the technology). Blowback uses and electrode inside the torch that is spring loaded, and with the torch at idle the torch electrode is pushed forward by the spring mechanism so it is in contact with the nozzle. When you trigger the plasma, DC power between the negative electrode and the positive nozzle is activated, and there is a dead short between nozzle and electrode. At the same time that the power is activated, an air solenoid activates and sends air to the torch (this takes a few miliseconds as air travels slower than electricity), once the air pressure builds inside the torch the air pushes the electrode back (Blowback) away from the nozzle, this creates an intense short circuit spark as the electrode breaks from the nozzle, the spark ionizes the air as it exits the nozzle and onece the power supply senses current flow (from electrode, through the nozzle orifice under air pressure, then to the material being cut), the DC power ramps up to cut power levels. To stop the plasma process you either move the torch off the material or shut off the trigger signal. After each cut cycle the air flow continues in order to cool the torch and consumables. So…the first torch fire takes enough time to get adequate pressure to the torch to move the electrode. The post flow cooling on most torches is about 20 seconds…and if you need the torch to fire while in post flow ,trigger the plasma again and the plasma opens another solenoid port to drain the air pressure from the torch…this allows the electrode to move forward and contact the nozzle, then the start cycle activates again. Since there was already pressure at the torch this start cycle during post flow is slightly quicker. So, every start that is triggered when the post flow not on will have a slightly longer firing time than subsequent starts during post flow cooling.

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To add to the differences in time between an initial start and a start during post flow: If you use the start signal initiation to start the time delay for machine motion…expect that there will be different times. The start timing can also vary with different air pressures (different points in the compressor cycle), as well as with different levels of electrode wear. If you look at the suggested interface wiring connections on Powermax systems that are purchased with a machine torch, you will find two connections on the CPC interface port that will provide a contact closure signal that will solve the timing issue. The signal is called arc transfer, and it is an output contact closure that closes when cutting current is sensed on the work cable (cable with a clamp between power supply and material being cut). If the CNC machine uses this arc transferred signal then the real time between the start of the cut on metal (not when the start signal was delivered) and pierce complete will occur on every start. This is the way most industrial plasma cutters use to coordinate the start of motion and to eliminate the big pierce hole that can occur if the motion delay is too long. Jim Colt

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I also have a cut master 42, and the long delay on the first arc is just part of how the machine works, as Jim Colt mentioned. When I am programming my cut paths, I use a 1.5 second pierce delay for the entire part, then once I am done I open the gcode in notepad and change the first pierce delay to 3 seconds and save the file.

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So if you paused more then 20 seconds then you know to have a longer start time. Is there a way to check for voltage then move(Could you add it to the gcode?)?

Did you take any pictures on how you hooked up your (cutmaster 42)machine to cnc?

Here is a couple pics of what my setup looks like. I connected the torch fire wires directly to the torch, instead of the machine. On the torch I opened up where it connects to the machine and used the Langmuir provided wire taps. In the manual you can find out which pins are for firing the torch. You are able to close up the torch connection so that everything looks factory. By doing this you are also not voiding the warranty on the machine.