Is my plasma cutter causing my air hose to rupture?

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I've been reading about plasma cutters for a few hours now and my eyes are crossing so I'm just going to ask this dumb question and hope someone can help.Recently; I have gone through two air hoses, ruptured in the same place, while plasma cutting. The first hose was older so that can be explained. However, the new hose was a quality hose from an industrial hose supplier. It says Goodyear 300PSI on it. I have my regulator set at 70 PSI per requirements of the plasma cutter, but I do not have a dryer (I know I should get one ASAP after reading everything). The compressor is rated just above the requirements of the plasma cutter. It is a cheap Chinese model bought from GiantTech. I also know this was a poor decision from reading old posts. I was cutting 1/4" plate at 50amps (max setting) both times. It has been working fine, but recently it has been hard starting the arc and cutting capacity has diminished (before the hose ruptured of course). I have replaced consumables, cleaned everything and improved the ground clamp.The hoses both ruptured just past the compression fitting after it comes off the regulator. I noticed the entire hose was very hot and stretched easily. I know it is a long shot, but could the plasma cutter be diverting its lost cutting capacity backwards through the air (especially if it has moisture in it) causing the hose to get hot and rupture or some variation of that? Thanks in advance! I'm totally stumped and don't know if I should try a new hose or attempt to repair the plasma cutter.Millermatic250Miller Spoolmate 200Miller Spoolmatic 1Lincoln tombstone with century DC converter1945 K.O. Lee company stick welder (looks like R2D2)Miller 30E feederHobart AH27 FeederMiller Thunderbolt AC/DC
Reply:Hose failure, nothing to  do with the plasma.Leo
Reply:I'm going to take a stab and guess the air compressor is oiless so the diminished cutting performance is either due to moisure in the air or inferior consumables or both and not oil mist in the air.  If it's oil lubricated then I'll toss that in too.What plasma cutter?  Is it a cheap Chinese unit same as the compressor?  If so, maybe it's reached its life expectance of two power ups which could explain its reduced cutting performance.My next guess is the ruptured hose is simply due to overheating as you've pointed out.  However, the overheating is from the normal results of compressing air and as you're running it at - or just below - its maximum capacity, the hot air is passing straight thru the regulator to the hose.  It sounds like you aren't using quick couplers on your air line at the compressor so there's nothing between the regulator and hose to help disipate the heat before it gets to the hose.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:Just a thought does your "compresser" have a tank and what size? and what is the cfm rateing? Cause if the compresser is running continiously (thus the hot air) and just keeping up it could be getting the hose hot enough to pop. How long is the running time from start to fail?Miller thunderbolt 250Decastar 135ERecovering tool-o-holic ESAB OAI have been interested or involved in Electrical, Fire Alarm, Auto, Marine, Welding, Electronics ETC to name a just a few. So YES you can own too many tools.
Reply:If your hose is getting hot its because the air coming out of your compressor is hot. You either need a compressor with a bigger tank, or figure out a way to cool the air before it hits your hoses.
Reply:And...I would suggest better quality air hoses. I have seen the low cost ones at Harbor Fright that have Goodyear stamped on them.....not sure that means that they are any good.   Many of the air line hoses in my shop are over 25 years old....never had a failure with 4 plasma cutters!Jim Colt
Reply:Thanks for all the responses guys! The plasma cutter is a 3 in one machine from Giant Tech. The compressor is a Black Max oil-less 5hp, 5.4CFM @90psi with a 30 gallon tank. It took it about 30min to break. I went and got the hose replaced and they upgraded me to a custom made hose that is heavy. I bet it will last 25 years. Heat from the compressor is the problem. I have a quick couple after the reg, but that thing was red hot after 15min. I'm thinking about getting another regulator and installing a "T" in the bottom of the tank to route the air out that was as the compressor is all red hot on the top where the stock outlet is. But I'm also thinking about getting a bigger compressor because eventually this one is going to overheat and die.The weird thing is using air tools working on my truck it never did it and that thing would run and run due to its low cfm. That is what made me think it was something to do with the plasma cutter. Maybe my compressor is on the way out because it is getting so hot? That old hose lasted a long time through tons of cutting and the new one lasted 30min.Millermatic250Miller Spoolmate 200Miller Spoolmatic 1Lincoln tombstone with century DC converter1945 K.O. Lee company stick welder (looks like R2D2)Miller 30E feederHobart AH27 FeederMiller Thunderbolt AC/DC
Reply:Go with the T route and get the gauge as far from the heat of the compressor as possible, my guess is it is runnning hot, hence the red hot gauge.
Reply:Actually, I'm just going to get a bigger one because by the time I do all that work and get another reg; I could find a good used one and sell or keep the Black Max for small jobs.Millermatic250Miller Spoolmate 200Miller Spoolmatic 1Lincoln tombstone with century DC converter1945 K.O. Lee company stick welder (looks like R2D2)Miller 30E feederHobart AH27 FeederMiller Thunderbolt AC/DC
Reply:Then I guess it is Miller Time, prefer Bud myself.
Reply:Originally Posted by weldbayThen I guess it is Miller Time, prefer Bud myself.
Reply:Originally Posted by ItsMillerTimeBud always gives me a headache, but to each his own. I found a few IRs and a farmhand with ~11CFM @90 for ~$400 so as soon as I close on this house I'll get one.Once I got the better air hose and tried it out; the plasma cutter works much better too. I'm glad it's not crapping out on me because I really don't have another grand to throw at a decent one. Right now it doesn't owe me anything. I paid $500 and it has been working for over a year. Even let my special roommate use it. He managed to go through consumables and the ceramic part twice cutting off a trailer tongue, but he knows what hes doing...
Reply:Originally Posted by brucerDo yourself a favor and spend the money to get a dual stage unit..
Reply:I agree, no reason for a dual stage unless you have tools that require high operating pressures. For most tools, single stage is optimum.
Reply:Here is the one I'm looking at: http://nashville.craigslist.org/tls/3358875210.htmlIts twice the cfm of the plasma cutter and made in the USA. I'm guessing it is a single stage, but I haven't went to look at ityet.Millermatic250Miller Spoolmate 200Miller Spoolmatic 1Lincoln tombstone with century DC converter1945 K.O. Lee company stick welder (looks like R2D2)Miller 30E feederHobart AH27 FeederMiller Thunderbolt AC/DC
Reply:Higher pressure in the receiver also means more air for the receiver volume.  175psi in 60gal is more air than 135psi in a 60gal receiver.