Plasma, I forgot, What does it do?

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I wanted a plasma cutter. I tried a cheap one, didn't like it. I sprung for a Hypertherm 45XP.Today I wanted to take a shortcut. I've had a couple pins on the Case backhoe repeatedly lose the snap rings. These pins are double end, no need for snap rings on both ends. My plan was two thick washers for each. One 1/2" thick fits the pin. Another is 1/4" thick will weld to the end of the pin. Today I confirmed; Plasma moves steel from where I don't want it to somewhere else I don't want it. I could have used the lathe, that'd take forever. As is, I've spent two hours grinding four washers to functional shape. I "cleaned up" with an acetylene torch.An optimist is usually wrong, and when the unexpected happens is unprepared. A pessimist is usually right, when wrong, is delighted, and well prepared.
Reply:

Originally Posted by Willie B

I wanted a plasma cutter. I tried a cheap one, didn't like it. I sprung for a Hypertherm 45XP.Today I wanted to take a shortcut. I've had a couple pins on the Case backhoe repeatedly lose the snap rings. These pins are double end, no need for snap rings on both ends. My plan was two thick washers for each. One 1/2" thick fits the pin. Another is 1/4" thick will weld to the end of the pin. Today I confirmed; Plasma moves steel from where I don't want it to somewhere else I don't want it. I could have used the lathe, that'd take forever. As is, I've spent two hours grinding four washers to functional shape. I "cleaned up" with an acetylene torch.
Reply:

Originally Posted by Willie B

I wanted a plasma cutter. I tried a cheap one, didn't like it. I sprung for a Hypertherm 45XP.Today I wanted to take a shortcut. I've had a couple pins on the Case backhoe repeatedly lose the snap rings. These pins are double end, no need for snap rings on both ends. My plan was two thick washers for each. One 1/2" thick fits the pin. Another is 1/4" thick will weld to the end of the pin. Today I confirmed; Plasma moves steel from where I don't want it to somewhere else I don't want it. I could have used the lathe, that'd take forever. As is, I've spent two hours grinding four washers to functional shape. I "cleaned up" with an acetylene torch.
Reply:a 45XP should blitz through 1/2". I've seen one guy take the outer shield off his 45XP, and with a very slow and careful cut, manage to get a relatively clean cut through a 35mm pin. I wouldn't have believed it except i know several people can cut 25mm clean with them.Even my cheapy cut40 can just about sever 1/2".Problem with plasma is that it doesn't burn up metal with oxygen like OF does - instead all it does is melt and move it. You have to plan for where that metal is going to be moved to... usually through the other side of the sheet... but if not, then it;s going to come back out...Murphy's Golden Rule: Whoever has the gold, makes the rules.
Reply:My son showed up yesterday morning with a cheap Land pride scraper blade his Father in law had bent into a curve with a 25 HP Kubota tractor. He wanted to straighten it & reinforce it.The plan was to remove the edge bolts & bolt a 3/8 wall Angle the length to stiffen it & add weight. His shortcut was cut 8   3/4" holes in 3/8 with plasma. He struggled with it, used some language the railroad workers 3/4 mile away (I'm sure) heard & were shocked!When he was done, I set out to make my four washers. I've seen a bigger washer used as a template. I have two circle cutters for it, but they work best on bigger circles. I cut free hand to a line. It doesn't cut square, it leaves a series of "peninsulas" inside the hole. Unlike a torch, I can't clean up irregularities, it just won't start except on a sharp edge.It pushes the steel around onto the back side of the plate. LET THE GRINDING BEGIN!Thinking about it this morning, I had painted with the compressor Saturday. I was at 40 PSIG. I asked Seth if he turned the pressure up. He assured me he had. I bet he did not.An optimist is usually wrong, and when the unexpected happens is unprepared. A pessimist is usually right, when wrong, is delighted, and well prepared.
Reply:Yea... they like to breath... running without turning on the air compressor doesn't last long...250 amp Miller DialArc AC/DC StickF-225 amp Forney AC Stick230 amp Sears AC StickLincoln 180C MIGVictor Medalist 350 O/ACut 50 PlasmaLes
Reply:Nope.5 HP compressor (Ingersoll Rand) 80 Gal tank, It was set over 100 PSIG. I'm not sure what the problem was, but air pressure wasn't it.An optimist is usually wrong, and when the unexpected happens is unprepared. A pessimist is usually right, when wrong, is delighted, and well prepared.
Reply:The plasma will throw error codes if pressure is low. Sounds like worn consumables or poor technique.
Reply:Hey Willie, I can tell you they don't cut like a torch, that's for sure.  Very unforgiving freehand in my opinion.  Every tiny movement is transmitted to that tiny little cut.With a torch, while supporting my hand appropriately, my cuts look very straight.Same technique freehand with my plasma, little saw-tooth like marks show up "for no reason."

Oxy/propane good....plasma bad....



Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:

Originally Posted by MinnesotaDave

Hey Willie, I can tell you they don't cut like a torch, that's for sure.  Very unforgiving freehand in my opinion.  Every tiny movement is transmitted to that tiny little cut.With a torch, while supporting my hand appropriately, my cuts look very straight.Same technique freehand with my plasma, little saw-tooth like marks show up "for no reason."

Oxy/propane good....plasma bad....




Reply:

Originally Posted by Willie B

Even if the cut at surface level is good, it's unpredictable what it'll do 1/8" away. I can cut a useable bolt hole with torch. Plasma, I have to grind back side clean (no easy task), then clean it up from the other side. Torch, if I get a sawtooth I can remove it, walls of a cut are square.
Reply:

Originally Posted by MinnesotaDave

The dross on the backside from plasma often comes off way easier with a chipping hammer than by grinder - in my opinion.That crap (dross) is super hard...


Reply:This is a chunk of 3/4" plate I was playing with freehand. The 65 will do it but I'm not always with it. I am getting better with it and use the O/A torch less and less. Oh, the bottom of the cut is untouched.


Reply:

Originally Posted by 12V71

This is a chunk of 3/4" plate I was playing with freehand. The 65 will do it but I'm not always with it. I am getting better with it and use the O/A torch less and less. Oh, the bottom of the cut is untouched.


Reply:I just sold my 100 amp Miller Plasma cutter

This is my freehand with oxyacetylene today on 3/4”.

Like Dave mentioned. Way easier cutting freehand with a cutting torch.  Better control with the longer body. Sent from my iPad using Tapatalk:
Reply:

Originally Posted by Lis2323

I just sold my 100 amp Miller Plasma cutter

This is my freehand with oxyacetylene today on 3/4”.

Like Dave mentioned. Way easier cutting freehand with a cutting torch.  Better control with the longer body. Sent from my iPad using Tapatalk
Reply:

Originally Posted by 12V71

Good point, I would love to see a plasma torch that mimics the balance of an O/A torch with a 90 degree head and a length that matches the average size and maybe even an uncomplicated top mount switch.... Might make it easier for us old dogs to adapt.
Reply:Wow! I can't do that with either, but life or death, I'd try with oxy.An optimist is usually wrong, and when the unexpected happens is unprepared. A pessimist is usually right, when wrong, is delighted, and well prepared.
Reply:

Originally Posted by Lis2323

Couple of old guys looking for the solution to a problem that doesn't exist to 99% of the welding population.  LOL.

Sent from my iPhone using Tapatalk
Reply:Plasma takes some practice. Guides definitely help the results. I have a homemade circle cutter that work down to about 2” diameter. I have used washers both id and od to cut circles. I think letting the drag shield rest on the material takes some getting used to. If you try to hold it off the work piece things get ugly fastMillermatic 252millermatic 175miller 300 Thunderboltlincoln ranger 250smith torcheslots of bfh'sIf it dont fit get a bigger hammer
Reply:

Originally Posted by farmshop

Plasma takes some practice. Guides definitely help the results. I have a homemade circle cutter that work down to about 2” diameter. I have used washers both id and od to cut circles. I think letting the drag shield rest on the material takes some getting used to. If you try to hold it off the work piece things get ugly fast
Reply:

Originally Posted by 12V71

Good point, I would love to see a plasma torch that mimics the balance of an O/A torch with a 90 degree head and a length that matches the average size and maybe even an uncomplicated top mount switch.... Might make it easier for us old dogs to adapt.
Reply:

Originally Posted by Willie B

Nope.5 HP compressor (Ingersoll Rand) 80 Gal tank, It was set over 100 PSIG. I'm not sure what the problem was, but air pressure wasn't it.
Reply:Hmmm.... I'm assuming that's the line pressure coming in and he would have another regulator set lower at the plasma. With my cheapy Chinese plasma I've been holding the pressure down to 90 lbs incoming and setting it around 65.250 amp Miller DialArc AC/DC StickF-225 amp Forney AC Stick230 amp Sears AC StickLincoln 180C MIGVictor Medalist 350 O/ACut 50 PlasmaLes
Reply:

Originally Posted by farmersammm

That is what I absolutely hate about my plasma.............................the ridiculous short length.  A long O/A torch adds stability, and helps to make straight cuts freehand.  I'm not a guy that can cut anything without resting my left hand on the plate, and using it to steady the torch.  Some guys can, but I never could.  I'll do it in a pinch, but I'm never satisfied with the results.I sold a couple Plasma's with 180 degree machine torches to a company that is required to cut 3/8 and 1/2" stainless aircraft type cable. They hung them from the ceiling with screen door springs. They could cut and cauterize the cables with one swoop. I'd say this is less than .0005% of the market.Thermal Arc 320SP ( Lorch )Cobra PythonsThermal Arc 300 AC/DC  ( Sanrex )ESAB 301i AC/DC  ( Lorch )Thermal Arc 161STL  ( WTL )Thermal Arc 190S  ( Sanrex )Cut Master 82, 42. Cut45 ( WTL )Victor Gas Apps.Boxes and boxes of welding crap.
Reply:

Originally Posted by Brand X

90 degree torch, and long handle is pretty worthless for anything other then bench work.
Reply:Sammy,ever use a 90 degree torch on a frame of a truck with limited space?? There is a reason way torches are 70/75 degrees, 180, and 90 degrees. il like top buttons/bottom triggers with a 70 degree torch like a PT-31 or bottom triggerSL-40 etc.. tiny size, and versatile . Not sure how many torch styles you have used. Two I am guessing..

I had quite a few, and even a 15 degree torch. for gougingEsab/Lorch ET-220iEsab 160i caddyThermal LM-200 Lincoln feedersThermal Pee-Wee 85sThermal 60i- 3phase /RPC powered (Beast)Thermal Drag-gun 35CINE 1500 Klutch 140i
Reply:A little late to the party, but I thought this was worth sharing. When you plasma cut a circle go counter clockwise. This is more important when running a cnc table but it helps in free hand too. Also if you go too slow the dross will be really bad. If you go really slow the kerf will fuse back together. It helps to watch the arc departure angle on the bottom side. At least when practicing to get a feel for it. When cutting you want a slight trailing angle not straight. Free handing plasma isn't as forgiving as oxy/fuel. Having the correct consumables for the material thickness helps big time.Also with Hyperthem Powermax machines they automatically regulate the air pressure. I feed my 85 a constant diet of 120 psi. That eliminates any potential air supply issues.Hope this helps someoneSent from my moto e6 using Tapatalk