Announcement

Collapse
No announcement yet.

plasma cutters - what one?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • plasma cutters - what one?

    I'm in the market.

    Here are my needs:

    Max size for plasma cut, 1/4" steel (absolute maximum, very rare)

    Average cut, 12 gauge mild steel

    I want to be able to do it at a reasonable speed.

    Who has the most affordable consumables in the name brand companies?

    Any advice?

  • #2
    Hyperterm Powermax 30.

    Comment


    • #3
      Hi. I use a Hypertherm Powermax 600 and I think you would be very happy with it. It will cut 1/4" steel as fast as you'd want to go by hand, and the consumables last a whole lot longer than any of the other brands I have any experience with. It will make a nice cut in 1/2" steel at a slower speed, and you can use 'fine-cut' tips for beautiful work in thin sheet metals of all types.

      Gordon
      Last edited by chipmaker4130; 05-21-2008, 05:41 PM.

      Comment


      • #4
        Hey guys. I've never run a plasma cutter before but I have thought about adding one to compliment my welding machines. What kind of air source do they require? Any general info about them would be helpful.
        Jonathan P.

        Comment


        • #5
          Crucial

          Originally posted by japcas
          Hey guys. I've never run a plasma cutter before but I have thought about adding one to compliment my welding machines. What kind of air source do they require? Any general info about them would be helpful.
          And that japcas is the item in the equation that too many forget.

          My plasma cutter specifies the litres per minute required at a specified pressure, so my compressor has to meet that critera - at the plasma cutter - so allow a margin for line loss in air pressure and delivery. Further, the air has to remain on after cutting for cooling of the cutter itself.The electricals and electronics are cooled by a fan. Thus air and power must remain "on" until cooling is complete.

          That "free air delivery" is not always clearly marked on a compressor and is very much less than the "rated" air use. My compressor "free air delivery" capacity is just over the plasma cutter requirement. I made sure I had as big a pressure vessel/reservoir as I could reasonably use so as to have a good back-up if the cutter got ahead of the air supply.

          The compressor may be a bit bigger and use a lot more electrical power than many anticipate.

          The plasma cutter can be an electrical power hog as well - so check it out.

          Power supplies will need to be pretty good to cope with the compressor and the plasma cutter running together.

          Plasma cutters are rated at the thickness of steel plate that can be cut at 10" per minute.

          Mine is 3/8" but will cut 1/2" at a slower rate.

          Just as in electric welding, the earthing is very important so as to reduced resistance.

          A plasma cutter will cut just about any metallic conductor - steel, copper alloy, stainless steel etc. They will cut through rust/corrosion/oxidation as well which is very handy.

          They do have a large diameter cutting head and it can be hard to see the cut/kerf at times - so access is not as good as an oxy/acet cutting torch.

          Keeping the correct distance of the cutting head from the work is essential both for quality and depth of cut as well as minimising use of fairly expensive consumables. It is much harder to control than oxy/acet and so most/many users will use guides for tip-to-job clearance as well as guides for keeping the cut on-line (straight edges and circle/arc guides - used as templates as with a wod-working router).

          They are really great for sheet metal or thin plate work as the cut is excellent as very high speeds.

          They do take some practice though.

          I don't use mine too often but I sure am glad I've got it when I need it!!

          Comment


          • #6
            Japcas, I'd have to look in the documentation for specific cfm requirements, but a 5hp compressor will run standard tips all day on the Hypertherm 600. My compressor is a 7 1/2 hp and it doesn't cycle all that often even with steady cutting.

            One thing to remember is that if you get a 40amp cutter, it will draw 40amps. No step-down transformer like with a welder. (The Hypertherm is an inverter unit).

            I just read OldTiffie's post, and I should mention that I use un-shielded tips 99% of the time because they don't block the view as he mentioned. I only use the shielded 'drag' tips when I cut using a template. I don't know about OldTiffie's machine, but mine is very tolerant of tip to work distance and I find it equally easy to use as the OA torch. The neat thing is: NO preheat time! The Hypertherm arc starts instantly, cuts a narrower kerf and produces about half the slag of an OA cutting torch. Also, you don't have to change tips for great cuts on any thickness within the range of your machine. (The exception being if you need a really fine cut in very thin ornamental sheet).
            Last edited by chipmaker4130; 05-21-2008, 08:04 PM.

            Comment


            • #7
              Agreed

              I agree with chipmaker4130.

              My set-up is in a domestic environment. I have a 240v 50Hz 2ph 60A/phase supply in my shop. The 2 phase is a hang-over from when I had (and still have and use) my 200A "choke-y" "stick" welder and a 2 phase supply for a then 2-element hot water service.

              I suspect that chipmaker4130's supply is considerably bigger or better than that!!

              So, I'd start at the plasma cutter specs, shop around for one that suits and again, check its requirements as regards electrical power and air supply. I'd add 20% to that air supply as the minimum spec for the compressor "free air delivery" (to allow for line losses - including the regulator) and then shop for the compressor and check its required electrical supply.

              My guess is that if there is a limited electrical supply that it will govern just what capacity compressor and plasma cutter you can fit in.

              As chipmaker4130 says, they are a great asset in the shop - but I sure wouldn't get rid of my oxy/acet set!!!

              Comment


              • #8
                Don't buy a Miller spectrum 375,expensive consumables and not capable of it's rating.

                I like the Hypertherm units much better and I also liked a Thermal Dynamics unit I used on a lease.

                Clean DRY air is a must also.
                I just need one more tool,just one!

                Comment


                • #9
                  I have had a Thermal Dynamics Pak Master 50 for about twelve years now. Now problems at all. Consumables are plentiful and priced about the same as all the rest. It cuts 1/2" stainless with a thin 1/16" curf. Slices up 16ga cold rolled steel like butter, just about as fast as I can sweep through the cutting template. I use thin cardboard for my templates. If Im going fast enough and dont jump onto the cardboard I can reuse the templates, doesnt burn it. I dont take any extreme precautions for dry air. Just a small drier mounted on the inlet side, small cheap one. JR

                  Oh, I gotta add though. The newer homeshop type units from TD appear a lil "cheaply" made. Not that looks are anything but I wounder if they have outsourced the manufacturing for some of their boxes. And mine wasnt cheap, bout 2500 twelve years ago.
                  Last edited by JRouche; 05-21-2008, 10:02 PM.
                  My old yahoo group. Bridgeport Mill Group

                  https://groups.yahoo.com/neo/groups/...port_mill/info

                  Comment


                  • #10
                    [quote=snowman]
                    Max size for plasma cut, 1/4" steel (absolute maximum, very rare)
                    Average cut, 12 gauge mild steel
                    Who has the most affordable consumables in the name brand companies?
                    /quote]

                    My plasma cutter is a HTP brand. The model I have is a 625. The air supply takes 70 psi at the machine.
                    The cutter is a 220V single phase machine with an output of 50 amps.
                    This machine is reasonably priced compared to a Miller. The customer service is excellent and parts are in stock. HTP is located in the Chicago area I believe.
                    The 625 will cut up to 5/8 inch thick cleanly, and sever cut 7/8 inch. On 1/8 inch steel plate it cuts like you would draw a pencil line, just as easy and just as quick. Check them out before you decide to buy some other brand. I have owned mine for 10 years now and never had a problem with it........pg
                    www.htpweld.com

                    Comment


                    • #11
                      I have a Lincoln Procut 25 that's been a very good machine. Cheap consumables.. a very nice sized torch.. all in all a good machine but it was pricey when I bought it(7 or 8 years ago??).
                      I then bought a Hypertherm 600.
                      Uses a lot more air than the Lincoln. I don't like the torch compared to the Lincoln.
                      However.. it's a lot more powerful machine and the price is lower than what I paid for the Lincoln.
                      The Hypertherm uses consumables a bit different than the Lincoln.
                      The Procut needed both parts replaced as they wore.
                      The Hypertherm uses the outer part the most. You get about 4 to 1 so it's fairly cheap to use.
                      Russ
                      I have tools I don't even know I own...

                      Comment


                      • #12
                        I have a thermal dynamics cutmaster 50 and it works great. I run it off a 60 gal. upright compressor and use a cheap air/water seperator. I don't think you can go wrong with thermal dynamics or hypertherm. Beware of the cheap cutters, my first plasma cost $1200 and was a total heap wish I could rember the brand.

                        Comment


                        • #13
                          I have a Hyper Therm Max 42 I picked up for $300 4 years ago. It was a show room demo model, but looked like new. Came with 6 extra of each of the consumables, I still have 4 each of them left.
                          Has had lots of use since I acquired it, zero problems, and gets pretty long life out of its consumables. For a dryer it came with a filter/dryer that uses a roll of toilet paper for the element. Have heard that this is not the best (by far) for a filter, but 4 years of use and as
                          I said, zero problems. It might be because I live in the desert and our humidity never gets very high. It takes about 6 CFM at 70 PSI if I remember correctly, and will cut a bit over 1/2" if I go slow. Parts seem to be readily available, judging by what I have found on the web.
                          Steve
                          NRA Life Member

                          Comment


                          • #15
                            I've picked up a like-new Thermal Dynamics Cutmaster 38 from the local Craigslist for about $800 with a pile of consumables and the matching cutting guide attachment kit.

                            After I sorted out that the torch was fitted with contact type tips, and that the clip-on metal guide that the previous owner had on the torch wasn't to be used, I've been quite impressed with the ease of operation.

                            It will run on 110 or 220V power, but works ~much~ better on 220. I have a 5hp-60 gallon quad cylinder Speedaire compressor and use a refrigerated air dryer, but it's not absolutely necessary; I happened across it and it followed me home. More for painting than cutting...
                            "Lay on ground-light fuse-get away"

                            Comment

                            Working...
                            X