plasma cutter help (1 Viewer)

[lx450landcruiser]

i have a hypotherm 380 and a husky 26 gal 1.7 horsepower to 5.5 peak horspeower compressor. its rated at 5.1 SCFM at 90 psi my plasma says it needs 60 psi at the at a flow or 4.0 however for some reason when i have everything hooked up and try and set the air rating on the cutter i cant get it to go up to 60 psi? any ideas? is it just a crappy compressor and i should get a bigger one or what?


thanks
mike

 

[hj60]

Our (at work) 50watt ThermoDyne uses bottled air.
I think you need something 3phase to build the type of SCFM/PSI you need for a burnzall.
Plus, I think you need really really clean/dry air for optimum performance. Ours has inline filter/drier.

But I'm a plasma noob, so I may be talking out my arse.

 

[lx450landcruiser]

yeah i have the filter but after talking to the welding shop guy hes like "ah yeah a house hold compressor does it as long as it meets the ratings" well then what the hells wrong wit mine?

 

[3pits]

what is the actual output on the compressor, it sounds like it is set lower than the 60 psi,,,

I have a thermaldynamics pack master 75 xl, if the pressure is lower than 40psi it cuts off, you GOTTO have dry air, a tank is good, but expensive, you dont need 3 phase, but usually home ac dont put out enough and the rating is not true I dont know how to compare it, but think of it this way, do you really think your HDepot compressor motor is putting out the same as a 5 hp lawnmower/5hp industrial compressor? probably not, there is a peak rating that is kinda bogus,,

back to your question, if you compressor will run air tools with a decent amount of efficincy it will probably run the plasma, check the out put on the compressor if it is not over 60 adjust it, if it is over 60 check for clogs or a pinched hose/cut hose on the gun side,, the solenoid in the plasma cutter may not beopening up, is it cycling thru the cool mode? pm me if you need to ,,good luck

 

[lx450landcruiser]

its a brand new compressor, and i had it at one point set to 90 psi in which case i could never seem to get the plasma up to 60 which is what they tell u to set it at. basically what they ask you to do is hook up the air line to the back of the plasma then turn a knob all the way down till you have air purging from the cutter. when this happens they ask you to turn knob 2 till the guage next to it is between the ratings they want which is basically 60. When i have the compressor turned up to alow for 120 psi comming out the hose it aloows for the cutter to get to the 60psi and the cutter works for about 5 min till the compressor kicks on. when the compressor kicks on the cutter seems not to work. does this mean the compressor is a no go? it would seem like it however what i dont understand is the cutter says it needs 60psi but i have 120 comming out of the compressor? if i turn the compressor to say 90 psi and adjust the guage on the cutter i can not get to the recomended 60psi? im stuck in a pickle here.


thanks for the help any more would be great.

mike

 

[Tools R Us]

Sounds like the pump isn't up to the job, the cheapo units are way overrated, what compressor is it?

 

[lx450landcruiser]

Sounds like the pump isn't up to the job, the cheapo units are way overrated, what compressor is it?

sheesh man i thought u read posts? its in the first post. a husky supposed to be rated at 1.7 to 5.5 or sumtin has 26 gal tank.

 

[Tools R Us]

Belt driven? Oilless? How many cylinder? 110 or 220 volt?

 

[Tools R Us]

This one is not going to cut it; EDIT; The links don't work, search item # at www.homedepot.com

168916

This one MAY work;

167501

This one would be better;

167502

 

[honk]

sheesh man i thought u read posts? its in the first post. a husky supposed to be rated at 1.7 to 5.5 or sumtin has 26 gal tank.

Your compressor isn't adequate, period. The cutter needs air FLOWING at 60psi not simply a static pumpup to the 60psi. Did I make that clear? I mean that there has to be a continual flow of air at 60psi and most cutters have little tolerance for variations.

I have a 60 gal tank and my compressor is rated at 16 cfm. I have the tank pressure cutoff at 130 psi and with that I can USUALLY make a 24" cut with my Thermodyne 38 cutter. More cut than that and I have to stop to wait for air.

Plasma cutters use LOTS of air! It's a pain in the ass.

 

[Steve C]

its a brand new compressor, it aloows for the cutter to get to the 60psi and the cutter works for about 5 min till the compressor kicks on. when the compressor kicks on the cutter seems not to work.
mike

Ok, so it runs the plasma cutter for 5 minutes?

The compressor has a pressure switch that will have either one or two settings. Most of the high dollar compressors have a switch two adjustments, one for the pump on pressur and one for the pump off pressure. A less expensive compressor will have only one adjustment with a fixed difference between the on and off pressure. (the compressor uses teh difference between the on and off pressures to reduce the cycling of the compressor. Remember, a motor experiences a big inrush current when it starts, so if you start and stop too often the motor can overheat)

My guess is that your compressor has only one adjustment. I would recomend two things:

1. Try to adjust the pressure switch so that it turns off at a higher pressure, which will also cause the turn on pressure to be increased.
2. try to see what kind of pressure drop you are getting from the tank to the plasma cutter. If that is too high, it would cause the plasma cutter pressure to be too low when the tank pressure is low.

 

[Steve C]

ONe other thing, since the compressor is not really big, I would be careful not to run it at more than may 50% duty cycle. If the pump runs for 5 minutes, it should rest for at least 5 minutes.

 

[alia176]

Mike,

I have the same plasma and a belt driven air compressor that is a 5hp, 7.1 scfm at 90psi and a 20 gal tank. I use 3/8" and 1/4" hose w/o issues. Your compressor is a tad under par I think.