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Getting ready to buy a plasma cutter, wondering how much a pilot arc style is worth to a newbie. I am a half-assed MIG welder but never used a plasma.

Main use would be to cut clean material, probably 1/4" max for most of it. Would like to be able to drag the torch along a guide or straightedge and preferably use a tip or standoff that allows contact with the material w/o eating up the consumables any more than necessary.

The other use would be to clean up old crap like cutting off spring perches, body mounts, etc. from rusty/dirty parts. Seems like a lot of prep might be necessary w/o the pilot arc feature.

The pilot arc feature seems to add quite a few bucks, thus the question.

Thanks for your input.
 

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I think pilot arc is a necessary feature. Difficult to cut expanded or screen without it. It's not the pilot arc feature on the machines that make them cost more, it's that the better machines offer it standard. As for being able to drag the torch tip and not thrash the consumables the better machines offer that as a stock feature. Consumable cost is another consideration. You might save a few hundred on a lower end model but over the life of the tool you are likely to spend more than that on electrodes and tips.
 

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That is a hard question I have never used a plasma that didn`t pilot arc.

This is something you don`t want to cheap out on.

Most name brand plasmas can use drag cut consumables the downside being if you lift the torch to high you will lose the cut.

Moisture in the air supply is the hardest thing on consumables
 

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I've used a few plasmas without pilot arc, and they work fine. Problem is, once you use one with a pilot arc, you'll never want to go back. Expanded metal and mesh flat out suck to work with using anything but a pilot arc plasma, and I've also noticed the pilot arc seems to help on dirty metal, but that could honestly be because they're generally just better plasmas.

I second Wyoming9's opinion, plasmas are not a tool to cheap out on. I made that mistake, bought a cheap plasma and it was cool for about a week, then it gets old. The cuts are never very clean, so you might be able to cut a rough shape quickly, but you'll spend the better part of a decade cleaning it up, it's quicker to just use a jig-saw or cut-off wheel. In the last year and a half I've used my cheap-o plasma twice, once to scrap and old truck bed, and once to cut a stack of 4x12' sheets of 18ga into more managable shapes. Other than that, it just took up space until a friend wanted it.
 

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Nothing like the Internets to bring opposing opinions out of the woodwork:D. I have a cheap plasma without the pilot arc (bought it 3 years ago), and I don't mind it. I have used one with pilot arc and they are much nicer, but for the money I have been very happy with my machine. Yeah, cutting expanded metal sucks but you can put a piece of thin scrap under it and it cuts much better. Besides, how often does a typical shade-tree fabber really need to cut expanded metal? For hacking off spring perches and the like it works just fine, better than the gas axe in most cases. My consumables seem to last pretty well unless I'm cutting really rusty, crappy stuff. Besides, consumables for my machine are cheap.

If you need it for a living a cheapo model will fail miserably, but I only bust out the plasma a few times a month and given my limited budget I have been 100% happy with mine.
 

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I've extensively used both. Pilot arc is really nice, but can wear consumables faster "if" your not careful and attentive. Non pilot arc is nice for newbies, because you can't burn yourself. :flipoff2:

My lil 40A china plasma is kicking butt going on 3+ yrs now without pilot arc. When it won't fire I just push and scrape the tip against the surface till it does. My buddy just picked up a Longevity plasma with pilot arc, they were running a deal within the last few months.
 

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Just to clarify:

A plasma torch with a pilot arc will fire a low power plasma arc in the air....this is a DC arc that goes from the torch electrode to the torch nozzle...and the force of the air blows the arc out through the nozzle (tip) orifice. The function? The pilot arc is designed to improve the ability of the plasma arc to transfer to the materials that needs to be cut......as the pilot arc approaches the plate, it burns through any surface issues (paint, rust, masking materials) and quickly transfers the arc....which electronically senses that current is now flowing through the work ground cable...and amperage ramps up (you will see the arc get more intense.

Older technology plasmas, and todays industrial mechanized plasma systems....use a pilot arc that is started with a high voltage, high frequency discharge between the nozzle and electrode to get the cutting air ionized. Newer technology air plasma systems use a "blowback start" ( a moving, spring loaded electrode in the torch) to ionize air, and are able to start a pilot arc without the use of high frequency.

Non Pilot arc torches have to allow electrical contact with the plate to be cut....by physically touching the plate (like scratch starting a TIG). These plasma torches use a high voltage, high frequency discharge that arcs between the torch nozzle (tip) and the plate that ionizes the air in this area, and gets the main arc transferred to the plate.

Pros and Cons?

Blowback style (non high frequency start) torches will transfer an arc to the plate from a fair distance (my Hypertherm Powermax45 will transfer from 1/4" away from the plate). This long transfer distance allows for best plate piercing capability in a mechanized application...by allowing the torch to stay back at a good pierce height which allows the pierce spatter from hitting the torch nozzle orifice....which cause nozzle wear and poor cut quality. The pilot arc also allows for rapid starts on rusty, scaly, or painted materials. Firing the pilot arc in the air will cause nozzle orifice erosion....and should not be done often. I once vivited a user of Hypertherm hand held torches that was doing some cutting inside large storage tanks....it was dark in there and he was using the torch pilot arc as a flashlight. His complaint...short consumable life......we solved his problem by buying him a flashlight.

Non pilot arc torches work well on clean metals, although having to touch start a torch is extremely tough on the torch nozzle (tip), as the arc starts with the nozzle in contact with the plate...and molten metal has no where to go except right back on the nozzle orifice. Once the orifice is no longer perfectly round...cut speeds slow down and cut edge angularity gets worse. Generally....a non pilot torch will not work on a cnc machine...as it is difficult to get the torch to scratch the surface to get the arc started....and, many cnc machines will be adversely affected by the high frequency required to start the torch. It is less expensive to manufacture a non pilot arc plasma system.....and that is the primary reason they are available.

Jim Colt Hypertherm
 

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Great tech. Thank you for that answer!
 

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Jim...well said!
 
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