Plasma versus oxy-fuel : beam demolition test

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David mentioned starting a new thread, so here it is.  Proposed test conditions:- Safety first!  So for the test, let's avoid loaded structures and heights for now.- Subject:  a steel structural I-beam.  Pick a big enough size that it takes some reaching and torch-muscle to get through.- Tools:  oxy-fuel cutting torch versus plasma torch.- place I-beam horizontally and cut off a chunk?  The best laid schemes ... Gang oft agley ...
Reply:If someone comes up with parameters for a test...i'll be happy to do the plasma part. It should be video'd in full. Maybe we get a local welding supply house interested in co-operating with this demo...and I may be able to pull some strings and be there as the plasma "trigger man".Any demo guys out there that want to help us set up a test?Jim
Reply:I've got some 200mm  12mm thick I beam i could tackle with my PM45.It would almost be like cutting 5/8 with a 1250
Reply:Need to make it 'tougher' or more like an actual building and not just slicing a piece of a beam?How about a bolted or welded connection?  A vertical beam and a horizontal beam, disconnect the horizontal with the torch and leave the vertical alone?Without getting into an actual building and picking two identical beams and doing a side-by-side, it is kind of tough to figure out just what conditions to set up in a test case to do in the shop/yard.  The best laid schemes ... Gang oft agley ...
Reply:Well Jim you can cross me off that list of running another test. I did my combat zone time already.Well I know Airgas did the setup for the Salvage yard test. Airgas brought the Hypertherm 1250 and 1650 over to their yard to compare to the Victor Pro O/A Torchs the salvage yard had bought from Airgas. They did a side by side cut comparison in various metals up to 2 1/2" thick. Too bad they didn't video tape it!  All the torch guys that swore by their torches quickly changed their minds to cutting with the Plasma Torches with 75' leads. The yard however kept 50% of its O/A torches since their was some stuff they felt they still needed those O/A torches for.Co-Own CNC shop:Miller :1251 plasma cutter, MaxStar 700 TIG/Stick, & XMT 456 Multiprocess Welder.&  2 Hypertherm HPR260's Plasma CutterSorry I had a bad stroke but now I am back.
Reply:One more thing I have not seen mentioned here.  $$$ of the consumables.  Be it Liquid O2 or tips for the plasma, I bet the plasma would be cheaper to run in the end including gas for a generator to run it.Cutting off bolt heads, or cutting out corner bracing is part of the job too.  I have no I beam to cut........  daym, I'm outa da race David Real world weldin.  When I grow up I want to be a tig weldor.
Reply:haha, im game.. ill see if i can get a peice of this beam and see how long it takes to torch it.-NateMiller Trailblazer 302gMiller Spoolmatic 30aLN-25 x 2Idealarc SP200Hypertherm Powermax 600
Reply:Torch off a big enough piece to send to me...I'll pay freight. I will video my complete cut with a Powermax1250...just tell me the rules!I have some I Beams in my pile....mostly small ones with 1/2" or less thickness. If you give me the dimensions on one you find....I have a buddy that owns a structural steel business...he may have the same size laying around.Jim Colt
Reply:Why don't we design a short length of whatever size beam with normal end connections....flange, bolted, welded, whatever. Then we will be able to do this sample cut in two locations...but under the same conditions. I'll fab on my end whatever is available in another shop for oxy-fuel cutting. First.....you better have a contest to find the best torch man...(person). Jim
Reply:Be sure the beam is coated real thick in red primer like most of them.
Reply:Set the parameters, show us all what the contest will involve (photos) so we can get set up too. I'll video a torch cut beam, if I can round up the pieces. Everyone will have to have basically the same material. This should be fun. Set it up, but don't get too extreme, an eight or ten inch beam would be all that's needed, eighteen inches will be out of my reach.Only when the last tree has died and the last river has been poisoned and the last fish has been caught will we realize we cannot eat money.                                         -Cree Indian ProverbSA 200 LincolnVictor Torches
Reply:Isn't this a slimmed down version of Denrep's challenge?"Any day above ground is a good day"http://www.farmersamm.com/
Reply:How high in the air, what's underneath it, and what's attached to it?"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Sorta like wearin' baby buggy bumpers"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Here's the picture.Tomorrow AM Jim Colt walks into his office at Hypertherm.  Calls the head of engineering and schedules a meeting in 30 min.  Meeting starts with Jim explaining the challenge to the assembled members.  Jim's challenge to the head of engineering--find us a way to get an HPR 260 under the covers of the PM 1250.  I know the 1250 will blow the torch away, but there's really no reason we can't stack the deck.  Head of engineering (who's also a betting man and of course a part owner of the company) replies back to Jim.  No problem Jim, should have your unit ready by the end of the week.This could get interesting.NV.  If you play your cards right, there may even be a 1250 in your future.Let me know the dimensions that are settled on and I'll try to scrounge up a similar piece of I-Beam from the shop.  I know I can cut it faster with plasma than with a torch.  Maybe I'll bring in one of the road guys who does this sort of job everyday to run the torch.  That should level the table.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:I gotta say one more thing before I get outta here.  Need to eat before I fall on my face, and need to contemplate my disc woes.First off,  I don't do demo work.  But I've cut a few long sections of stock that buck when you finish the cut.  In my case it only craps up my tip because molten metal gets on it.  Have to clean the tip.The long reach of a cutting rig is a real plus as far as I can tell.  I assume the plasma is the short lil' thing I've seen.  That's too close to dangerous stuff as far as I'm concerned.  That craps gonna move when it's finally cut, and who knows what direction it's gonna move.Doesn't seem like a real world test IMHO."Any day above ground is a good day"http://www.farmersamm.com/
Reply:The problem I see with plasma being an effective "demo" tool is its lack of portability.    I have a powcon plasma cutter that is run off of the welding leads like an LN25.    Its still a pita to have to have a compressed air source in the field that will keep up.For a shop environment or scrap yard plasma 1000X over O/A but in the field having the O/A on a cart with out having to tether it to a machine that needs fairly decent amounts of power combined with another machine to generate a clean compressed air source makes it not very practical for demo.Any Sizeable steel demo jobs are much much much more profitable when handled with a scrap shear mounted on an excavator.   A LaBounty scrap shear on a decent sized excavator makes an impressive scrap pile in no time and has lower cost per ton than either plasma or O/A when preparing scrap steelVantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:I took a few pictures of some typical structural steel  demolition cuts today.Attachment 32356I wonder if the beam with my foot on it could be a close match with NV's.Attachment 32358The dirtier and thicker the stack the better for plasma, right? How about the connection in the inset?How about the twins?Attachment 32357Who wants to reach between there with a short torch and separate them?Good LuckLast edited by denrep; 10-19-2010 at 11:36 PM.
Reply:First picture: Plasma can cut through all three layers in one pass. Nada on oxyfuel. Or plasma the rivet heads off....you can do it with a cutting nozzle or a gouging nozzle.Second picture: The key for a good plasma is not how rusty/dirty/painted the cut is where you begin your cut....but a clean connection where the ground clamp is. I would probably grind a clean spot for the ground clamp. This was not always true.....to transfer to non conductive surfaces you need a good strong pilot arc. I would dare say either the Hypertherm 1250 or 1650 would have no problem transferring and cutting the rusty piece in the picture. Our older systems may not have worked well....and many competitors systems will not do this either.Third picture: I would not stick my hand in there...torch or no torch. Why chance ruining a long torch? Devise a block to keep the stress from pushing the beam together....or take the whole assembly down and cut it on the floor. You could also pierce and cut around the rods from the outside. I'm sure there's a way to do it without getting someone injured.This thread is great....some real world applications are coming to light and we can put all of our heads together to uncover many difficult situations with demo/scrapping...and maybe develop some safe practices....or even new tech nology that will work.It would be great if someone with experience doing I Beam demolition could step forward and develop some parameters for test cutting that are real world.Jim Colt
Reply:Okay, so to start nailing down the pink-slip run's  terms, so far we have:The 1250 will sever the expected 1-7/8" thick stacked  material all day, without need for duty-cycle breaks.The 1250 will sever this material in a single pass, at least two times faster than  oxy-fuel Correct?By the way, the twins - Oxy fuel operator would wedge the nearest cut drop, or wooden block,  between the flanges and cut without concern for torch damage. In a typical day's demolition work, many such difficult to reach cuts will be encountered. If it's all about time... Let's be fair, how much time would we add for short-torch plasma's extra cuts and fumbling to separate two members such as the twins?Good Luck
Reply:OK, JimColt pointed out the fact that the plasma cutter would cut thru three layers of painted, rusty, corroded steel, where the torch would not. I don't think there's much to argue about there. Having used a torch extensively, I'd have to agree. Now, I don't and have never owned a plasma cutter, not that I wouldn't. I have very little experience with them. But, as Dualie pointed out, portability is an issue with them. (Unless something has changed I'm unaware of) I-beam demolition in the real world (mine, anyway) always seems to take place 40 to 60 feet in the air. A plasma cutter powerful enough to cut the suggested parameters is NOT portable and would have to be slung or hung close enough to whoever is doing the cutting to be functional, and re-slung or hung at each cut. This would figure into the time and the cost for each cut.  A torch on the other hand can have an untold limit of hose added and has the portablity to work at these heights without special slings etc. Unless I'm completely off-base, (wouldn't be the first time, or even the second!) that makes the torch the hands down winner in this contest, before it's even started. Personal opinion.Only when the last tree has died and the last river has been poisoned and the last fish has been caught will we realize we cannot eat money.                                         -Cree Indian ProverbSA 200 LincolnVictor Torches
Reply:Originally Posted by gizzardgutzOK, JimColt pointed out the fact that the plasma cutter would cut thru three layers of painted, rusty, corroded steel, where the torch would not....
Reply:Denrep,The first statement: "The 1250 will sever the 1-7/8" thick stacked material all day, without need for duty-cycle breaks."  I'm not sure where you got this from...but, yes it will sever 1-7/8 inch stacks....as long as there's not much gap (maybe less than 1/16"). And no, it will not do it all day without a duty cycle break. You would need many more kW of power to do it all day.....and if you know of an operator that will cut 1-7/8" material with a hand torch at 100% duty cycle...let me know, I'll hire him (her). You can cut the 1-7/8" periodically....and probably at 50% duty cycle.....and that means 5 minutes of full power cutting and 5 minutes of rest. If there was a lot of this 1-7/8 stack cutting to do, I'd step up to a 100 Amp Powermax1650And the second: "The Powermax 1250 will sever this material in a single pass, at least two times faster than oxy-fuel. [B]What material? If it is 5/8" or 3/4"....yes, The 1250 will cut at least twice as fast, and will pierce in about 1 second if you need to pierce. And you can lay the torch on the plate (makes life easier if you are upside down, or have one trembing hand holding on to the scissors lift rail as I would) and / or guide the torch on a straightedge template. If it's 1-7/8" material, no, the oxyfuel should be faster.....1-7/8" stacked material? Will the oxy-fuel even cut it?[B]Also.....each plasma cut will be single pass....no multiple passes allowed. If you are trying to cut too thick....and blowing back material into the torch....then you don't have enough power and you should change to oxy-fuel or a bigger plasma.Heck, we can duct tape a broomstick on the plasma torch if we need a longer torch....it's certainly been done...and maybe this will show the manufacturer of the need for a different torch style for some applications.Jim Originally Posted by denrepOkay, so to start nailing down the pink-slip run's  terms, so far we have:The 1250 will sever the expected 1-7/8" thick stacked  material all day, without need for duty-cycle breaks.The 1250 will sever this material in a single pass, at least two times faster than  oxy-fuel Correct?By the way, the twins - Oxy fuel operator would wedge the nearest cut drop, or wooden block,  between the flanges and cut without concern for torch damage. In a typical day's demolition work, many such difficult to reach cuts will be encountered. If it's all about time... Let's be fair, how much time would we add for short-torch plasma's extra cuts and fumbling to separate two members such as the twins?Good Luck
Reply:I'm just trying to lay out the parameters for our test.We need to get each item down, so that 1250 and oxy-fuel can either pass or play on a test that represents what NV may find on a typical beam job.With a web thickness of 5/8", the typical AISC connection will be the 5/8" web sandwiched between two 5/8" connectors, that adds up to 1-7/8"No big deal, make mine 2" or 2-1/4" just to be sure.1-7/8" inch is light work for oxy-fuel. Any old shop torch will cut 2" material with ease, and it's no big deal for a scrap cutter to process 2" and heavier plate or structural, ALL day long. Originally Posted by jimcolt...and if you know of an operator that will cut 1-7/8" material with a hand torch at 100% duty cycle...let me know, I'll hire him (her).
Reply:Jim you beat me to it. ONE time I wanted to write my girl friends name on a local water tower.  NO big deal, I taped a spray can to a broom stick.  Another time I was cutting down a tree in a bucket truck.  There was a widow maker ( a large dead limb that went up and around).  I bungeed my chainsaw to the bucket, put a rubber band on the throttle and ran the bucket from the ground controls.  We could do the same for the plasma if needed, or since Jim is involved in this, we will some day end up with a longer plasma torch for safety reasons.Using a cutting torch to cut thicker you need more O2 and a bigger tip.  For the plasma, you need more amps.  We need to have the torch have the proper size tip and the proper size machine to do the job.A torch with a #1 tip will be as useless as a 20 amp plasma.The work will be bid by the JOB, so time is money.We have a local hockey arena that was bid for demolition when scrap was $300/ton.  By the time the job was under way, scrap went to $30.00 a ton.......Edit:  A bigger torch tip than needed will do no good.    A bigger plasma than needed will be faster yet.More Edit:  Denrep I can see the pic right above this post the part Alfred is pointing to has been cut from 3 different angles.Last Edit:  I see 3 of us are on line.  Its wed at 10:30 am Shouldn't we all be at work making sparks?Last edited by David R; 04-29-2009 at 10:26 AM.Real world weldin.  When I grow up I want to be a tig weldor.Then you have a great job for oxy-fuel. 100% duty cycle all day long means continous cutting...no coffee, no bathroom, no lunch! Never pull the torch away from metal. Duty cycle in the welding industry is based on a 10 minute cycle. A 50% duty cycle means 5 minutes on, 5 minutes off. Or 20 seconds on, 20 seconds off. I have seem a few plasma applications where the torch fires....and remains on for 8 hours continuously, and at full power. These applications are mechanized....and the plasma (properly sized) performs quite well!Duty cycle with plasma power sources and welding power sources is more complicated in reality than just stating 50% or 80%. The factors involve: Amperage output x voltage output, or killowatts.....cutting at 100 amps on 1/4" is different than cutting at 100 amps on 1.5"......on 1.5" the arc voltage is higher.....which means the power supply is producing a higher output as measured in kW.....producing more heat. Other factors...ambient air temperature, input line voltage and frequency. Every manufacturer has different test protocol to determine the duty cycle ratings of a power supply.....Hyperthem has the toughest standards. When we say 80% duty cycle.....for most applications with a hand torch it is almost impossible to exceed. That being said....if someone says they will hand cut at 100% duty cycle...I won't argue with them....even though I'm pretty sure they will not do it....and I will suggest either a bigger plasma, or perhaps they should go look for another process that may provide 100% duty cycle.I'm trying to be realistic....and offer plasma capability by todays standards. certainly we cam come up with things that the plasma cannot do, and that only a couple of humans can do, just as I can come up with some scrapping jobs that oxy-fuel cannot do. I think the purpose of this thread should be to determine where a properly sized plasma is usable in the field, what is advantages and shortcomings are. If your trying to trip me up...and make me say something that I don't think is possible....that's not going to happen.Jim
Reply:Originally Posted by jimcolt ...I'm trying to be realistic....and offer plasma capability by today's standards....
Reply:Sounds good to me.....let's get the test going. And just for correction.....in a flat plate drag race....on 5/8" steel, not counting your preheat......I'll cut 3 times the distance (with an 80 Amp plasma) than you or anyone else with any oxy-fuel torch will. That's my claim, and I'm stickin to it.I fully agree that there are other factors involved in the demo project.....so let's sort that out, and determine what process has what advantages. Jim
Reply:I use a Porta Power to keep the beams spread apart while cutting them. I use to do alot of bridge work my 20 ton Porta Power will separate and support most beam while providing protection. To bad you are not closer to my farm Jim as I has tons and tons of used steel beams both from NY state bridges, Army Corp of Engineer projects, and building construction. Some of those beams are 3" thick. I would send you a couple of pieces of that.Co-Own CNC shop:Miller :1251 plasma cutter, MaxStar 700 TIG/Stick, & XMT 456 Multiprocess Welder.&  2 Hypertherm HPR260's Plasma CutterSorry I had a bad stroke but now I am back.
Reply:Denrep,To set the record straight....you keep pushing this duty cycle thing.....you say the operator will have to stop and let the plasma rest. Not true with a properly sized plasma. The time you take to go from one cut to the next is more than adequate to achieve the duty cycle rating of the plasma torch. If an operator can hold the torch in his hand and cut it...the plasma will fire and cut when the trigger is pulled (no striker involved). There is no post flow cool down required either (old plasma systems had this).....as soon as you pull the trigger...the torch fires.A properly sized plasma system will be close to 100% duty for a particular job.....and will be able to exceed this rating for many short bursts (short being 1 or two minute cuts. If duty cycle needs to be explained in more detail...let me know. It can be very confusing!I had a PM from a 1250 user the other day wondering if the cooling fan was defective because it never came on......he was cutting some 3/8 material at 80 amps......and a lot of it. The cooling fan is thermostatically controlled (keeps dust out of the power supply)...and comes on when a certain temperature is reached on internal components.....this happens far before the max temp is achieved. In most applications.....an operator with a hand torch cannot exceed the duty cycle rating. Any feedback from users on exceeding the duty cycle on a Hypertherm unit....maybe with the exception of our 120 volt units?Jim
Reply:Where's the trigger on this "torch onna broom stick" arrangement? Are remote triggers available or do we tape it down and hope it holds?
Reply:As I stated before even with a 75' whip the plasma is going to need constant repositioning.   Another factor would be if a piece of drop falls on the torch hose its NBD.   I keep 2 complete torch repair kits in my service truck.   now if a piece of drop falls on the plasma torch lead im going to be raging pissed.I have put torch bottles in the basket of a man lift and used them all day long without having to come down.     with a plasma your always going to have a tether to the ground constantly in the way of maneuvering the man lift.    weather it be the S.O. cord from the power source to the plasma AND the air line from what ever your air source is OR the lines from the power source to the hand torch of the plasma theirs always going to be much more chances of something minor putting you out of production.Using a plasma in a real world demolition environment is a bad application of this technology.   In a scrap yard or a shop im plasma all the way.   In the field O/A makes much more sense.Theirs MORE to this idea than simply Time in the cut.   Factor in time spent rigging for a cut and moving between cuts theres no way that plasma will ever make sense when looking at the $$$$Even with my Thermal Arc over the line (think voltage sensing feeder) Hooked to the vantage 500 and  a 220V compressor plugged into the vantage also and just one lead and a air hose going to the work area.   it is still a PITA to move around the unit.   The only real time I made good money with it was doing bleacher repairs which was over 1200' of strait line burning through rotted and Swiss cheesed 3/16" mild steel.Vantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:Originally Posted by jimcoltSounds good to me.....let's get the test going. And just for correction.....in a flat plate drag race....on 5/8" steel, not counting your preheat......I'll cut 3 times the distance (with an 80 Amp plasma) than you or anyone else with any oxy-fuel torch will. That's my claim, and I'm stickin to it.
Reply:To me, it looks like the 80 amp plasma needs to cover 17 x 3, or 51 inches in either 27 or 31 seconds, depending on if the judges count the 4 second booger cut.Last edited by denrep; 04-29-2009 at 10:37 PM.
Reply:Dit dot dit ddot dit.  Stop the presses. News flash.This humble reviewer just has to say that the Oscar belongs to Denrep Productions LLC.While character develoment was marginal at best, the script was beyond reproach.  Building to the climax was artfull, if not masterwork.  Slow ticking minutes to the slam bang crescendo.  A masterwork.  Deserving a place on the star studded walk of fame.Kudos to the grips, catering was marginal, but makeup was even worse.Despite the crude, somewhat caveman approach to developing the plot, the  story cut through the fog like a beacon in a stormy night.America, this proves that the small budget effort can outshine the best that corporate schlongers can spit out of the studios.  A triumph for the little man.  Long on heart, full of wisdom, and a bulwark against the snakecharmers.Two thumbs up!!!!!!!!!!!!!!!!!"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Playing soon in theaters near you.See it"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Sam Charlie
Reply:Sam - I was to slow to edit the last post of mine Attached ImagesCharlie
Reply:OK.....I'll get the camera setup in the shop today, find some 5/8" plate......stop in at Hypertherm and borrow a Powermax 1250 (I have a 45 and a 1000)....then figure out how to post it.....may take me a while! Should be easy.....my cut quality will be virtually dross free, square edge and all of the pieces will drop. Jim
Reply:Hi Jim...  stop in and borrow me one tooo lolnot knockin my hypertherm by any means but the TD have the extension chord deals to add torch length but some bigger hypertherm come with longer leads ....to solve the distance to machine problems hose still in the way though I guese. but if it's alot faster it would pay a laborer to drag it LOL and do everything else.... I'm tired of doing it all myself I'm not 20 anymore.so if it's faster im in cause that's money and O/A  gas is 50 miles away here... hmmm air is around though and power readily available so that would persuade me to plasma for sure on a big demo job Fuel would cost me more than  O/A costs LOL.woo hoo I'm watchin  gotta see this    GuysLincoln 225 Tombstone,Miller Big 20,Hobart 180,150' Argon,A/D hobart hood 22 Ton Log splitter,79 F350 dump eats 4.75 TONS and still turns cutters,grinders,And a  Hypertherm POWERMAX 30
Reply:Jimcolt, We look forward to your run.For me, unfortunately used ½" - 3/4" plate is golden right now, so I made the test cut on heavier plate. If someone puts up a pink slip, I would cough some 5/8" plate. But you have to remember, I don't stand to earn a dime from cutting equipment sales, or design improvements which might be garnered from this comparison, -regardless of the outcome- so I can't really raid the steel rack or use too much  production time to drag race torches. I don't know why not, we used to drag race loaded dump trucks!  Maybe we could excuse some of my dross, rough cutting, and small boogers, -none of which are an  issue with demolition cutting- since I did cut nearly twice the specified 5/8" thickness, and made three turns, as often required on a beam connection cut... Or if someone brings a pink slip, I'll buy some used 5/8" plate and run again.I'm not making excuses, just explaining. I probably left the booger when I started to change my lean angle too soon, not wanting to waste cut overrunning the third turn. If the cut-off side of the plate was a little larger or had some weight on it would have dropped despite the booger.Maybe once we sort out the demolition cutting comparison, we'll go for machine quality cut comparisons. For your run here, don't bother with appearance or straightness, this is the demolition-derby, not the Autorama. Good LuckBy the way, I may have the next event of the  demo-cut triathlon  lined up...Stainless pipe!Attachment 32382To the folks that don't give a rip about demo cutting, I need to go put my DC controls troubleshooting hat on now, maybe that job will make for a better general interest thread. Last edited by denrep; 10-19-2010 at 11:36 PM.
Reply:OK....I was able to procure the equipment and a piece of 5/8" plate....One thing I forgot to mention about the 1250....which makes it nice for field work....is that it will run on any voltage between 190 volts and 600 volts, single or 3 phase. No tap changing...it auto detects the voltage. At the low level voltages that are single phase.....it draws about 60 Amps when you are cutting 1" material......when I attempt the 1-7/8" the amp draw may go as high as 90 Amps....due to the longer arc, which requires more power. I'll be running on 208 volt single phase in my garage. Here's the unit and the steel for this first test cut.....now I have to figure out how to post a movie.....can anyone give me some pointers? I think it is an MVI file from a Canon camera.Jim Attached Images
Reply:The Powermax1250 is wired and ready to fire. Plugged in the air....hard wired it to my panel.....15 minutes total.Pictures:1. The crustiest piece of 1/2" steel in New Hampshire. Ground off some crud to find steel for the work clamp.2. Transfers and cuts as good as clean steel. Strong pilot arc is a must to do this. Paint will not bother this system either...in fact if the paint is on the bottom side...dross goes away (if any). wear long sleeves cutting this crap.....lots of hot particles of dirt and rust fly everywhere!3. Another weird piece of what looks like forged steel. The edges are about 1-1/8" thick, the bottom 1/2".4. After cutting......took about 13 seconds. I have only ever cut with a 1250 at trade shows....so I'm getting used to the torch.Now I'll figure out the camera and try to simulate Denreps cut from this morning.Jim Attached ImagesLast edited by jimcolt; 04-30-2009 at 02:21 PM.
Reply:OK....let's see if this YouTube video comes through. This is my first run with the 1250. I soapstoned two  3x4 rectangles......which is at least the same distance (17")  that denrep did....17 inches. On my first run through it looks like I was travelling slow in a few areas.....with air plasma you are near full speed with about a 30 degree tail in the sparks....anyway I achieved about 29 inches per minute by my calculation.Hat's off to Denrep...your definitely a good torch man!......while I am faster with the 80 Amp plasma, I'm not that much faster......but a much prettier cut with the plasma (I know that doesn't matter in this case)....instant start and piercing. I'll practice a little more and get the speed up....I think I can shave about 25% off. I'd go get a 1650....but no single phase power at my home shop....in fact I think I'm a little limited with my low line power.....you get a little more oomph at 240 than at 208......and definitely more if your running on 3 phase.Jim   Last edited by jimcolt; 04-30-2009 at 04:45 PM.
Reply:Jim,Nice, clean cut.You're right though, you could speed up the cut considerably.  Arc is exiting straight down indicating that the travel speed is a little slow.The 208V vs 240V input power is also reducing your cutting "power" by, I suspect, about 10%.That channel shaped piece in the previous posting was even more impressive.  Denrep is definitely good with a torch (lot better than I am), but I'm still liking plasma.I think with enough "added criterion", ie additional plates, tabs, bolts, etc that we could find applications where the torch is better suited.  Seems to me, and I've just sat back and watched without saying a word, that the OP's original question was simply about cutting an 18" x 5/8" structural I-Beam.  He even considered doing the job with his PM 600 but realized that it would be a little underpowered.  Now we've gotten into the whole world of scrapping and a bunch of other "what if" type questions.Last edited by SundownIII; 04-30-2009 at 05:16 PM.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:I'm so excited!  Good Stuff!!!     The Lord has declared, "This is my work and my glory--to bring to pass the immortality and eternal life of man"  Moses 1:39Link: My name is John, and I am a member of The Church of Jesus Christ of Latter-Day Saints.-- ColdCreekWorks.com --
Reply:What is the contest guys? Was looking up info on cutting an I-Beam and came across this.. I have a HPR260 on a Motoman UP20MN...
Reply:Ok, got some Hag on the stereo, can o' beer closeby.  Fingers limbered upThe plasma cutter does a nice job.  No doubt about it.  I'm sure the speed will improve too.Great tool if you have a 240v generator handy, a few feet of extension cord, a way to lift the cutting unit to where it has to work, and don't forget the 120v cord ya gotta drag along to power the grinder needed to make a nice shiny ground.  Hope I didn't leave anything outOOPS,  I forgot the scratch to buy all the goodies  Whadaya got tied in a electronic marvel like this??  Might be a tad more than a cutting rig.Now a little word about the fingersys, and toesys, not to mention the ol' nogginsys.  Seems a fella is might up close, and personal, with one of these lil' wonders.Better have monkey arms too.  Need a pretty good reach.A drop cut is a beauty to see, and great thing to be able to do (ask fellas just starting to learn to use a torch).  It depends on what's droppin', where it's droppin', and what's under it (yours truly).While the plasma has it's place, I'm not sure it's in the demolition arena.Just one dummy's opinionWhere do you want to be standing? Attached Images"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Sink or swim, fightin' the current, I'm sidin' with Alfred on this one"Any day above ground is a good day"http://www.farmersamm.com/
Reply:I believe the original original question that brought on the showdown had to do with demolition.Reverse engineering"Any day above ground is a good day"http://www.farmersamm.com/