Will my air compressor run this plasma cutter?

[drummerdimitri]

I'd like to purchase a Hypertherm Powermax85 plasma cutter and would like to know if my current air compressor will be able to cope with it.

Here are the specs for the air inlet pressure/flow on their website:

Cutting: 189 l/min (400 scfh, 6.7 scfm) @ 5.9 bar (85 psi)
Gouging: 212 l/min (450 scfh, 7.5 scfm) @ 4.8 bar (70 psi)

On paper, my compressor should be able to keep up with the plasma cutter since its specs are as follows:

50L tank, 250l/min or 8.8 cfm.

Only issue is that I don't know at what pressure that airflow is rated at since it is not sfcm (90 psi) if my understanding is correct.

If not, what size compressor should I be looking at for my shop?

 

[matt_i]

The easy way is to hook it up and see what happens, that's a low-cost option.

I think its going to drive a lot of constant running of the compressor while you are cutting, and it might not be up to that duty-cycle for the long-haul.

What type of HP or kW motor are you using?

In North America a very common shop compressor is powered by 5hp ~3.7kW electric motor.

Part of it will also depend on how you intend to use the plasma...little snips and cross-cuts will require different duty cycles than big continuous curves in large sheets, or a CNC table where it can be on most of the time the pathway is moving...

 

[drummerdimitri]

The easy way is to hook it up and see what happens, that's a low-cost option.

I think its going to drive a lot of constant running of the compressor while you are cutting, and it might not be up to that duty-cycle for the long-haul.

What type of HP or kW motor are you using?

In North America a very common shop compressor is powered by 5hp ~3.7kW electric motor.

Part of it will also depend on how you intend to use the plasma...little snips and cross-cuts will require different duty cycles than big continuous curves in large sheets, or a CNC table where it can be on most of the time the pathway is moving...

Luckily my compressor is a belt driven, 2HP electric motor with 100% duty cycle so it can run continuously while I cut large metal plates but I am not sure whether or not it can maintain the required pressure while doing so.

Will also be building a sandblasting cabinet so maybe a larger compressor is needed but it doesn't hurt to just test and see.

It is my understanding that the Hypertherm will stop functioning in case the working pressure drops below the normal threshold so no damage can be done to the cutter's head in that case.

 

[matt_i]

Sandblasters come in many sizes but if its a model that you stand next to which is mounted to the floor, I think you're going to need a larger compressor.

 

[drummerdimitri]

Sandblasters come in many sizes but if its a model that you stand next to which is mounted to the floor, I think you're going to need a larger compressor.

Yes, that's the one I'm thinking of building.

I know it's just a matter of time until it needs to be replaced so will do so when the time comes.

 

[American Locomotive]

I do not think a 2HP compressor will create an honest 8.8 SCFM. Probably more like 6-7. I think it would be marginal, but probably keep up.

 

[rlitman]

I do not think a 2HP compressor will create an honest 8.8 SCFM. Probably more like 6-7. I think it would be marginal, but probably keep up.

Agreed. However, remember that unless we're talking about CNC plasma cutting (I hope not), then the plasma cutter will not be under continuous use anyway, and will consume less than the projected numbers.

 

[drummerdimitri]

Agreed. However, remember that unless we're talking about CNC plasma cutting (I hope not), then the plasma cutter will not be under continuous use anyway, and will consume less than the projected numbers.

I will eventually be investing in a CNC machine and mount the plasma cutter to it so for now it will do I guess

 

[BD1]

I suggest contacting HYPERTHERM tech support for their recommendations.


Sent from my iPhone using Tapatalk

 

[lis2323]

Sandblasters come in many sizes but if its a model that you stand next to which is mounted to the floor, I think you're going to need a larger compressor.

Unequivocally yes.

 

[ducksface]

Your compressor lies.
That's at a certain temperature with a surge at the intake, side not the supply side. It's not what it puts out as air constant.
Figure half of it.

Your plasma cutter lies and needs more air than they say on any cut needing any depth.
.
Whatever the plasma asks for you need at least another 1/3.

Others will disagree. How compressors are rated is in 1,000 interwebannets places.

But.
Give it a try.
My plasma cutter waaaay out runs a husky 26 Gallon compressor..
But
You can do the
Cut wait cut wait method and do just fine.

Just a note:
The nephew has cool little 26lb plasma cutter with a built in compressor. It does 1/4" OK and smaller just great.
We've been using it instead of firing up the compressor and dealing with hose and importability.

 

[Professor Fate]

I would say a 50L tank is pretty small for any reserve air. You may think about up-sizing the compressor anyway.

By the way, how are you doing in Beirut after the blast, Covid stuff and the economic issues? My in-laws live there and I get to hear a lot. I've also been several times and really like the area and Mounir's in the mountains is one of my favorite restaurants.

 

[drummerdimitri]

I would say a 50L tank is pretty small for any reserve air. You may think about up-sizing the compressor anyway.

By the way, how are you doing in Beirut after the blast, Covid stuff and the economic issues? My in-laws live there and I get to hear a lot. I've also been several times and really like the area and Mounir's in the mountains is one of my favorite restaurants.

I will definitely be getting a larger screw compressor in the near future but since I already have so much to invest in, it will not be a priority for now.

I'm still alive thanks for asking! It's too much change, too quickly and so I'm feeling a bit shaken up but I guess it will pass and well get our lives back sometime soon.

Yeah, I've yet to meet anyone who doesn't like that restaurant. I for one can't stand it as there's much better food to be had elsewhere but I understand the appeal form a tourist's perspective.

 

[drummerdimitri]

I ended up buying the Powermax85 model but just realized the 125 model has 100% duty cycle at max amperage.

Now I'm having buyer's remorse and thinking if it would've been the better choice as I will eventually get a CNC table and adapt the plasma cutter to it.

Realistically, I doubt I would ever need to cut more than 20-25 mm of material but I am afraid of accidentally exceeding the duty cycle and causing harm to the machine.

If the Powermax125 is the better option for me, maybe I can still upgrade it as it is still brand new (dealer purchase).

 

[lbhsbz]

Yes, but the question is for how long. I have an 80 gallon compressor that I let fill up, then unplug it and plug in the plasma and cut until it drops below 80 psi...then take a break and let the compressor refill. I didn't have enough amps to the garage to run the compressor and my plasma at full tilt...so I only set up one plug to prevent overloading the circuit....I could get plenty of cut time before I was ready for a beer while the compressor filled up again.

 

[rlitman]

I ended up buying the Powermax85 model but just realized the 125 model has 100% duty cycle at max amperage.

Now I'm having buyer's remorse and thinking if it would've been the better choice as I will eventually get a CNC table and adapt the plasma cutter to it.

Realistically, I doubt I would ever need to cut more than 20-25 mm of material but I am afraid of accidentally exceeding the duty cycle and causing harm to the machine.

If the Powermax125 is the better option for me, maybe I can still upgrade it as it is still brand new (dealer purchase).

Well, the 85 has a 100$ duty cycle at 66A, so figure that on your table's limits. You can cut a lot at 66A. Especially on a modern nozzle.

Anyway, my understanding is that it should shut down on duty cycle and not be harmed.

 

[Cyclotronguy]

At about 50A through my Powermax 65 I can cut about 10" inches of 1/4" plate before I have to wait for an IR Garagemate (2HP portable) to catch up I'm plumbed in with 20 ft of 1/2 " id air line straight out of the the receiver, rather than the original piping

Going through the supplied IR pressure regular will cause a warning on the Powermax 100% of the time at anything over 30A.