Plasma cutter air compressor?

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I have a job coming up in which a plasma cutter would be VERY helpful. I've never needed one before so I bought one of the cheap chinese ones, LOTOS I think for $300. I am aware of the cautions out there on these machines but assuming the cutter will at least work for this job and it will pay for itself right away. However, I'm also not too fond of air compressors as we rent out our basement so I try to be as quiet for them as I can be working in my garage. That being said, I do not have a compressor but need a cheap one that can power the plasma cutter. I will be cutting 1/4" sheet metal and I would like to have a compressor that will at least have enough air to cut 2 feet. Since I'm already being loud with it turning on, I don't mind if it needs to run continuously. I've been looking at the HF compressor for $141 right now, the 10 gallon 2.5HP compressor. I think the cutter needs about 4cfm at 60psi and that compressor says it has 5.3cfm at 90 so that should work, right? Or even the one the next size down is on sale for $99 but it's only 8gal and 4.5cfm at 90psi. Like I said, the compressor will ONLY be used with the plasma cutter, and maybe as a blower and tire filler occasionaly. Thoughts?
Reply:I dont know about that brand of plasma cutters but I do believe that you get what you pay for. Before I purchased one, I found that the cheaper ones really exadurate what thickness they can cut. Atleast cut well. You may be able to do it but it may look like you cut steel with a dull hatchet. Be ready to deal with rough edges and lots of slag if it get through at all. I have a 30 gal Speedaire hooked to mine and I will get about 3' of really nice cuts on 16 ga before it gets a little rough and the compressor kicks on. I have used it to cut 1/4" but its slow going and meticulous. Also keep in mind, there is a bit of a learning curve on using plasmas if you never have before. Its not as simple as it looks. Take some time and practice on some scrap fine tuning your psi and amps. I dont know how much you have to cut or what you are making but a small used O/A rig goes for $150-$200. A torch is quiet too. Goodluck,RGRG_______________________Hobart 187Northern Tool Plasma 375Harris 85 O/A Rig (Ireland)
Reply:I will be given somewhere between 4-6 4'x8' sheets of 1/4" sheet metal and I'm making some giant boxes out of them. The edges don't have to be super clean because they will be welded together. I've never actually used the machine, but I know someone who has the same one, and I've seen videos and reviews of people saying it cuts 1/4" just fine. It claims the severence cut is 3/4". And I thought about the O/A setup, but I need something that will cut fast and I don't need to keep going to get the cylinders refilled.
Reply:The Lotos won't be very fast on 1/4"....but should cut it OK.  Are you planning to run the Plasma on 120 volts or 230 volts? The compressors sound too small (both) to me.....but I am not familiar with which torch style you are getting with the Lotos.....they have used a couple of different torches.....and it is the torch that determines air flow rate.Jim Originally Posted by EcondronI will be given somewhere between 4-6 4'x8' sheets of 1/4" sheet metal and I'm making some giant boxes out of them. The edges don't have to be super clean because they will be welded together. I've never actually used the machine, but I know someone who has the same one, and I've seen videos and reviews of people saying it cuts 1/4" just fine. It claims the severence cut is 3/4". And I thought about the O/A setup, but I need something that will cut fast and I don't need to keep going to get the cylinders refilled.
Reply:May sound opposite of what you want, but if you stay away from an oilless compressor it will be quieter.  More then likely bigger also.  I had a 15Gal Coleman (given to me)  screw in the piston came out and it seized.  So I bought an 80 gal Campbell Hausfeld that is an oiled compressor.  It is 220V however single stage.  It is quite a bit quieter then the Coleman.  I can run my impact, cutoff wheel, die grinder, etc...Some of them kinda work the compressor and make it run but I see it this way.  I got the tires broke loose on my wifes Caviler (1 tire with the compressor kicking on, but it broke the lugs loose)  my 03 2500HD wouldn't even break them loose.Now I can take 2 tires off my truck then it will kick on.  Huge difference between not being able to run anything and being able to run everything.  (not the best, but enough)My plasma.  (a Eastwood "smaller one can't remeber the amperage) will drain the tank and kick on the compressor.  Takes a little bit, but if I am running it constant maybe 8 minutes it will kick on the compressor.  This one however the compressor can keep up with and fill the tank.  The cutoff wheel however is like a blow gun and it cannot keep up with.All that said, I would go big with an oiled compressor.  Quieter and it will actually do something.  For a woodworker small is fine, for "us" who use more powerful metal/automotive tools.  Need a bigger tank, more powerful compressor.Changing the intake to allow better air flow in may help also.
Reply:I will be running it off of 220V. I've seen some decent deals on craigslist that I've been looking at. I'm starting to lean towards the 8gal gas powered compressors. Like I said, I really don't mind noise once I start using it, the people in the basement can get over it. But those compressors say they put out like 11-14cfm and they can be used anywhere.
Reply:Originally Posted by EcondronI will be given somewhere between 4-6 4'x8' sheets of 1/4" sheet metal and I'm making some giant boxes out of them.
Reply:I was thinking a saw for the sheet metal as well. Even one of those circular looking metal cutting saws would be good and I may still purchase one of those, but I went with the plasma cutter because I also need to cut some doors out of some old propane tanks. The final product will be a couple trailer mounted BBQ smokers with a 5'x3'x3' warming box, possibly double walled, attached to it.
Reply:I am interested in how that Lotus plasma works I have read it is the same as Eastwood but cheaper. I have look for a good compressor and I think I am going with a Harbour freight the one that cost $339 It has very good reviews it seems to be close to the same units other places sell for $799 who knows it is probably all made in same Chicom factorySent from my SAMSUNG-SGH-I317 using Tapatalk 2
Reply:My Eastwood lasted 20 minutes.  220 unit, cutting 12 gauge metal.  clean dry air and plenty of compressor.  i fell for tHe warranty and moneyback guarantee.  Still,waitIng for my refund. THey have had it back for a week now.  Gonna buy a thermal dynamics once my card is credited.  Good luck,Jay
Reply:Call me crazy but cutting 1/4 i would just use a torch.That said I don't buy cheap junk when I don't have to. And i am usually flat broke... anyways, Why buy an inferior machine and a small compressor?Miller Dynasty 300 DXMiller CST280Miller Maxstar 150 STH
Reply:Your plasma cutter should come with minimum required compressor specs...  Oil lubricated for sure.  If you're doing a lot of cutting, the compressor will be running a lot.  Oilless ones tend to be super noisy and don't take the abuse of high duty cycle operation very well.Belt driven, low RPM compressors will be quieter, more reliable, and last longer than direct drive units.More CFM is better.  Period.  Large tanks are, in the case of most store-bought compressors nowadays, a crutch to allow the sporadic use of high-flow tools while cheaping out on the compressor pump and motor.  An 80 gallon tank might be appealing, but if it's only got a 2 hp compressor pushing 8 CFM into it, you're going to be waiting forever for the tank to refill.I run a 60 gallon 5HP 21 cfm PRESSURE LUBRICATED compressor at home.  It keeps up with every tool in my arsenal, and runs quiet and cool.  The pump is older than I am, and it'll probably still be chugging away long after I've kicked the bucket.There's no point in buying a compressor that will outrun the duty cycle of the machine though.  If your machine has say, a 30% duty cycle (dunno what it really is...?), then you only need about 3 minutes of air.  It will have 7 minutes to catch up before you can resume cutting.Slicing up several whole sheets of 1/4" material is going to be painstakingly slow with a small cheap machine and a small cheap air compressor.Personally, I'd forgo the mini plasma and go with Oxy-Propane.Another option would be to pick up a big bottle of compressed air or nitrogen.  No worries about duty cycle, recovery rate, or moisture.  Just gotta make sure you don't run out.Last edited by anickode; 03-06-2013 at 09:38 PM.You didn't build that.'85 Miller AEAD-200LE
Reply:Yeah I'm starting to regret purchasing that plasma cutter. But I bought it so relatively cheap I think I can turn around and re-sell it on eBay and even make some money on it. I think I'm going to go with an o/a set up. I heat metal a lot for bending and I use a MAP gas torch for that and it can take a while so the o/a is pretty attractive to me for that. Say I were to buy a couple larger tanks of Craigslist, like 120cf or so, about how much are they to get filled? My 120cf Argon/co2 costs me about $30. Is it more or less? Also, what's a typical flow rate? Lastly, how long will it take to cut 4' of the 1/4" sheet metal? Just looking for some ball park numbers.
Reply:Originally Posted by forhireIf I was making a bunch of giant boxes a plate saw with a guide would be my first choice. I know you already bought the plasma but you would have been money ahead with a saw I think.
Reply:I actually don't lol I've been getting by with my jig saw and curvy edges!
Reply:A good OA rig is hard to beat. That is one area where I spent a premium dollar on even though I am just a hobbyinst. I have a 7.5hp 22cfm Quincy air compressor that would easily run a Plasma (and I do want one some day) but from what the previous posters have said, I think I would still use an OA for 1/4" steel plate. If I am not way off, the waste should at or slightly less than the thickness of the material..........If only I could cut a bit straighter.....And I have also found that cutting uses way less gas than heating/bending does so maybe that is not as big of a savings when it comes to plasma.
Reply:Your kerf on axy fuel torch should be nowhere near 1/4" when cutting 1/4" plate.for thinner styff, they make sheet metal nozzles for use with a straight edge.  They have flat sides and only a single preheat jet, and will cleanly and quickly cut thin sheet. Oxy propane is THE way to go for large amounts of cutting.  You just can't best the price.You didn't build that.'85 Miller AEAD-200LE
Reply:Originally Posted by anickodeYour kerf on axy fuel torch should be nowhere near 1/4" when cutting 1/4" plate.for thinner styff, they make sheet metal nozzles for use with a straight edge.  They have flat sides and only a single preheat jet, and will cleanly and quickly cut thin sheet. Oxy propane is THE way to go for large amounts of cutting.  You just can't best the price.
Reply:A small standard cutting top like a 00 or smaller still puts more heat into the metal than is needed to sustain the oxidation process.  It will definitely cut better than a large tip, but will still tend to overheat, leaving rough blobby edges.Take a look through the Victor catalog.  They have all sorts of interesting cutting tips for various jobs.You didn't build that.'85 Miller AEAD-200LE
Reply:Originally Posted by anickodeA small standard cutting top like a 00 or smaller still puts more heat into the metal than is needed to sustain the oxidation process.  It will definitely cut better than a large tip, but will still tend to overheat, leaving rough blobby edges.Take a look through the Victor catalog.  They have all sorts of interesting cutting tips for various jobs.
Reply:Originally Posted by EcondronYeah I'm starting to regret purchasing that plasma cutter. But I bought it so relatively cheap I think I can turn around and re-sell it on eBay and even make some money on it. I think I'm going to go with an o/a set up. I heat metal a lot for bending and I use a MAP gas torch for that and it can take a while so the o/a is pretty attractive to me for that. Say I were to buy a couple larger tanks of Craigslist, like 120cf or so, about how much are they to get filled? My 120cf Argon/co2 costs me about $30. Is it more or less? Also, what's a typical flow rate? Lastly, how long will it take to cut 4' of the 1/4" sheet metal? Just looking for some ball park numbers.
Reply:chuckhole something that may help you cut straighter.If you clamp a piece of angle iron flat on the piece your cutting, vertical side towards the cut.You can run your O/A torch, propane, plasma against the angle and end up with well a straight cut.Just have to get the distance from the center of the torch to the angle correct.
Reply:Sorry if I am hijacking the post with additional questions. I am in the IT business (not welding) so I should know better.KCB37,Thanks for the tip. I will try that and much appreciated.