Lincoln 625 - Torch not firing all the time

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flasharc
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Lincoln 625 - Torch not firing all the time

Post by flasharc »

Have a Lincoln Tomahawk 625 running my table using sheetcam and mach3. Trying to figure out why my torch isn't firing every time. I can sometimes get threw a whole program and cut just fine then go to another part and have issues. The first pierce it normally works but going to the next pierce and it won't. Back the program up to pick up where it didn't fire and it will fire go to next pierce and it won't. I don't have a THC. I changed all my consumables that didn't do anything. I changed out my break out board thinking it might be the issue that didn't change anything. I changed the pierce height and the cut height that didn't help. I downloaded new updates for mach3 hoping that would help. I always keep the ground on the metal I'm cutting. I'm not sure what else to check. Need Help!!!!
jimcolt
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Re: torch not firing all the time

Post by jimcolt »

Probably time to contact Lincoln tech service...they should be able to help with torch misfiring issues. When a Hypertherm exhibits those symptoms....these would be the common things to check:

- Make sure you are using genuine consumables from the torch manufacturer, not low cost online deals! These have shorter life and will misfire more often.
- Make sure inlet air pressure is within the manufacturers specs. If you are assuming the pressure on the gauge 50' back at your compressor is correct....trust me it is not. Install a gauge at the inlet to the plasma and watch the pressure there while air is flowing at the torch....you will see it is a fair bit lower than at the compressor. If it drops below the manufacturers minimum.....this can cause misfiring.
-Input line voltage. Be sure you have the system wired to an adequate circuit, using proper sized cable. Cable too small will result in a voltage drop....which is a common cause of misfiring.
- Your torch is a blowback design which has an electrode that must slide freely, and is spring loaded. Make sure you have replaced all the parts....the swirl ring (or whatever Lincoln calls it) wears out and causes the electrode to stick.....this will cause a misfire. Cahnge the swirl ring and the retaining cap. Make sure the retaining cap is only snug, not overtightened.
- Inspect your torch (internally), ensure it is spotlessly clean (no dirt, grease) and that the spring loaded plunger is operating freely. Contact tech support if any questions.

Jim Colt Hypertherm
flasharc
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Re: torch not firing all the time

Post by flasharc »

Thanks Jim
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