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Plasma cutting settings

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Plasma cutting settings

Postby Farmwelding » Sun Feb 12, 2017 12:29 pm

How do you figure out the settings for plasma cutting specifically amps. Is there a rule like 1 amp for every ten thousandths thickness or something like that?
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Re: Plasma cutting settings

Postby ldbtx » Sun Feb 12, 2017 7:43 pm

If you have a Hypertherm system, you can go here and download the manual for the machine. The manuals have a "cut chart" that recommends setting and cut speeds for various thickness metals.

I would presume that other manufacturers have downloadable manuals on their sites. If not, you can download a Hypertherm manual and try those settings.

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Re: Plasma cutting settings

Postby Rudy Ray » Sun Feb 12, 2017 11:31 pm

It is dependent on your material thickness and travel speed.
On my CNC table I can cut 1/4" at 55 amps and 50 in/min or at 40 amps and 80 in/min.

If you are cutting by hand, how fast can you move the torch smoothly? Just like with a OA torch, erratic movement interrupts the cut.

Also, tip life is greatly extended if you are not running it at full capacity. The only time I run mine on full throttle (55 A) is 3/8" & up and sometimes 1/4" if there is a lot of cutting.
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Re: Plasma cutting settings

Postby jimcolt » Tue Feb 14, 2017 12:50 pm

There are a lot of different torch designs and consumable parts choices from different a single "rule of thumb" simply will not apply to them all. As already posted....with major manufacturers (like Hypertherm) you get detailed recommendations for pierce height, pierce delay, cut height, cut speed, amperage and choices of consumables for each material type and thickness. The nozzles (some manufacturers call them a tip) used in good quality plasma cutters are precision manufactured and engineered to provide best cut quality, speed and consumable parts life for a specific thickness range. Plasma cutting nozzles almost always perform best at their maximum amperage recommendation. Operating a 45 amp nozzle at 30 amps will decrease the arc energy density and produce lesser cut quality, operating a 45 amp nozzle at higher amperages will quickly erode the nozzle orifice....shortening the life of the consumables.

If your question alludes to determining the correct plasma cutter for the application....then it is always best to look at these three specs from the manufacturer of the plasma cutter:

1. Recommended Production Cut thickness. The thickness that the systems duty cycle is rated at. Cutting thicker and you will get shorter a shorter duty cycle.

2. Recommended Maximum Pierce Thickness. This is the maximum thickness that the torch will typically pierce (in a mechanized cutting application) without damage to the consumables.

3. Maximum Severance thickness. Under ideal conditions the maximum thickness that you can cut with an edge start (piercing not recommended).

Jim Colt Hypertherm

Farmwelding wrote:How do you figure out the settings for plasma cutting specifically amps. Is there a rule like 1 amp for every ten thousandths thickness or something like that?
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Re: Plasma cutting settings

Postby exnailpounder » Wed Feb 15, 2017 8:27 am

I set my plasma all the way up no matter what I am cutting. It cuts better and the consumables last longer. And an air dryer in your line also really makes a difference. Thumbs up for Hypertherm!
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