Life of Plasma cutter electrodes.
Electrodes donít seem to last very long on my Hypertherm 45 machine. On the incoming Air line I have a 5 micron paper filter element right upstream. It is new. I think this will provide dry air for the short term. In the near future a Desiccant type dryer will also be installed. At $7 a piece for the electrodes my cutting costs are higher than I would like. Is there something that I am doing wrong? Does the ground influence this? I am still using the cheap ground clamp that came with the machine. In welding I am kind of a fanatic on good grounding normally tacking a removable ground onto what ever I am welding on. Not being able to do that on this cutter I guess I need to grind my clamping point clean. Any thoughts about why the electrodes are so short lived?
are you plunge cutting ? my 1/2" thermalarc does not like just straight plunging. if i swirl the torch to blow the hole the tip smiles at me. i also have a canaster type auto paint type air filter and have for quite a few years. change it every 6 months or so. im just sayin . . .
If you are so inclined post here,
There is a member named Jim Colt that works for Hypertherm and is very knowledgable.
Kinda hard to quantify consumable life when your'e doing miscellanous fab work without actually logging the feet cut, run time, or starts. Always a subjective thing for me.
I've got a Hypertherm 1000, filter is some kind of coalescing thing with three little cannisters. I'm guessing two hours cut time before arc gets excesssively fuzzy and bent. Might swap sooner if I need a really nice cut, or run em till they drop on nasty dirty rough work. Two cut hours translates to several long days of serious fab work for me.
Feel like I get a lot of cutting done for the money, but just had a deal where I burned through two pairs of consumables in about 15 minutes each. Arc began to blow sideways after just a couple minutes and the nozzle showed an obvous egg shape. Turned out the barrel cracked at the threaded ring where the shield screws on. I think this let the nozzle cock over in relation to electrode.
$36 for a barrel, $24 for "wasted" consumables....such is life.
I think your ground is fine if it cuts at all, piercing is hard on them, replace consumables as a pair, and dryer air is better air.
Last edited by SVS; 02-21-2011 at 05:10 PM.
I too am put off by the high cost of consumables. I found that you could get a lot more service out of the electrode by punching the tungsten forward until it is again flush with the carrier. I can usually get away with this 3 or 4 times. When the tungsten is completely consumed, I have had success re drilling the carrier for an interference fit to a TIG tungsten. I use 2% Thoriated but the next time I am going to give 2% Lanthanated a try as it may give longer service.
A 5 micron air filter gives you clean air, thats all. I recommend the motorguard filters.
The ground clamp that comes with it is fine. No need to change it. 45 amps is a pitiful amount of current when it comes to that clamp. If your arc transfers then your good to go. You dont need to go crazy to get a good ground.
Thats not tungsten in the tip of a plasma electrode. It is Hafnium. it melts when you strike an arc creating a pool that helps stabilize the arc.
Like others have said, piercing is one of the hardest things on consumables. Start at an edge if you can or drill a hole to start. It will be easier on the consumables, the torch, and you as you dont have all that slag blasting back at you.
The good folks at Hypertherm say the electrodes are tungsten or hafnium, but nonetheless, the thoriated tungsten runs just fine.
Originally Posted by macona
Last edited by mf205i; 02-22-2011 at 03:54 AM.
Just a few thoughts.
Used to install and service CNC Plasm & Oxy/Fuel cutting tables -
Consumable life - #1 Clean Plasma Gas. Moisture and oil in the air will affect electrode life. #2 Starts & Stops - most of the wear occurs on starts & stops. If you can, try to do chain cuts where you cut multiple parts per cut. If you are cutting by hand tilt the torch so the slag has someplace to go other than back up into the torch. Keep the tip clean and that slag can keep the electrode from moving away from the tip as that shortens consumable life (assuming that your torch does not have hi-frequency start) Make sure you initial height is good so you get a quick arc transfer. Don't drag teh nozzle on the work as that messes with the arc path and damages the nozzle and electrode. Check for gas leaks in the plasma gas lines. the plasma gas helps cool the tip as well as becoming the plasma stream. Control your cut height as that will help keep the arc from messing with the nozzle. Watch your speed - when you are cutting the right speed you will get a very nice stream of sparks.
If you are doing much cutting, you might get better consumable life using straight nitrgen. Hypertherm, on their production machines uses Nitrogen start and then switches over to Oxygen for clean cuts on steel, and then switches back to nitrogen when turning off the arc.Nitrogen and air (70% nitrogen) both require the cut surfaces be ground to get clean welds (something about nitrides in cut surface causing porosities in the welds...)
What is on the material that you are cutting - one shop had to use Pickled & Oiled Steel (military contract, go figure) and the consumable life dropped drastically. Cut clean steel and the consumable life went back up.
Last edited by kf2qd; 02-23-2011 at 04:02 PM.
A Good Ground And Dry Air Is A Must, i have 3 yes three Big Dryers on my Pro 25 And the only time I have had a problem is when a friend forgot to hook up the Ground when i let him in the shop to use it, So now I don't let any one use it,
I found with my Miller spectrum 700 that the best way for me to make the tips last longer was to use an 1/8 inch stand-off..even if you can "drag" the tip on thinner metal i find that dragging with the stand-off helps..it wasnt cheap. i think i payed 30 bucks for it.
Also good tips about the starting, stopping and plunge cuts being the biggest wear areas..
not sure if you can see the stand-off in this pic or not..it is all i have..
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