Miller Electric

Welding Discussion Forums

Home » Resources » Communities » Welding Discussion Forums

The forum is currently undergoing maintenance and is in a 'read-only' mode for the time being. Sorry for the inconvenience.

  • If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.


Announcement Module
No announcement yet.

Black Iron can I weld it?

Page Title Module
Move Remove Collapse
Conversation Detail Module
  • Filter
  • Time
  • Show
Clear All
new posts

  • Black Iron can I weld it?

    I'm wondering if you can weld black iron? is there anything special you need to do to weld this metal?

  • #2
    Black Iron...

    Hey hit_em,
    Yes, you can weld black iron fairly well if you take some time to prep.. Is this pipe or old black-iron furniture? The safest way to repair black iron is with oxy/acet. and using silver-solder. If you want to weld it, you must prep the weld area with a grinding wheel or sanding disc, brush with acetone or toluene to degrease, pre-heat the weld area to at least 250 deg.(I use oxy/acet. with a rosebud). I MIG my black iron repairs with ER70S-6, C-25 @ 18CFH, and tack each end, then manually do a pulse-like feed of the wire to maintain heat. After the weld is finished, I apply the rosebud again to maintain a slow reduction of heat. You can also totally cover the weld area in white sand to slow cooling rate. This will generally work well to keep the black-iron from cracking. Must cool very slowly. Hope that helps a bit....Denny


    • #3
      I'm talking about black iron pipe, the stuff you can get at any hardware store. I want to weld the pipe and fittinigs together. But I think the fittings might be cast iron can this be welded? The reason I'm wanting to do this is I dont have a pipe bender to make a 90 degree corner. does anyone know anything else I can do?


      • #4
        cut the metal at 45s then weld em together idk wht u plan on making though


        • #5
          black iron welding

          Back in the old days most of the local racers got away with black iron pipe. In the 60's and 70's they just used a stick welder, then in the 80's everyone was migging it. Black iron pipe has been banned in racing for many years now but was commonly used and welded in the past. As for welding fittings to it I have done it with both stick and mig with good results. Dave


          • #6
            it's going to be pipe thats goes on the bottom of a barge for anti freeze to run through it and gets cooled down from traveling in the water so there has to be like 6 runs of 15' for each engine. this is why I need to turn 180 degrees. does this make sense? so can the pipe and fittings be welded together? I think the fittings are cast iron, can anyone verify this? if it is cast then wont they crack after a period of time?


            • #7
              Originally posted by hit_em View Post
              it's going to be pipe thats goes on the bottom of a barge for anti freeze to run through it and gets cooled down from traveling in the water so there has to be like 6 runs of 15' for each engine. this is why I need to turn 180 degrees. does this make sense? ...
              There must be some reason that you don't want to use regular 90* elbows to build up the returns???


              • #8
                I dont know where t get 90 degree angles or else that is what I would do. the only thing close I have found are the quick fab squaretubing elbows, but the guy wants round tubing and I dont kow where to get elbows and I dont have a bender. I'm openedto suggestions I was just considering this way as an option.


                • #9
                  come on guysI need to have an idea to present to the client tommorow, looking for some good suggestions. he want this done right away.


                  • #10
                    this black iron pipe your talking about sounds to me like black pipe (plumbing pipe painted black, bevled at both ends ushally), wich is just mild steel, they also make mild steel weldable elbow's to weld to black pipe


                    • #11
                      is there anyspecial place to get mild steelelbows? or would they sell the where the sell black pipe?


                      • #12
                        Those fittings are forged steel, it seems a major supplier would have access, we use them at work, but I don't know where we get them, Try King Archetectual Metals, Dallas, Baltimore, LA...they ship


                        • #13
                          Hit em, here are the links, king is at the bottom....Hope this helps, Paul





                          • #14
                            thanks for the help guys, I gave it a try and it seemed to weld fine, now I'm going to get some end caps and pressure test it tommorow. How can you tell if it's cast iron or forged steel?


                            • #15
                              Hit Em,

                              Sounds as if what you're doing is what we refer to as a keel cooling system. If you're planning to operate this vessel in salt water, you may as well forget about using the pipe you're talking about. It won't last a season in salt water.

                              A much better option (one we've used for years) is to use copper pipe and solder the 90 angles in. The size of the engine will determine the length and number of runs.

                              The copper will last longer in salt water and is also a better conductor of the heat you're trying to displace.

                              If you gave me some more info concerning HP, gas or diesel, and where you'll be operating, I'll give you a wag at how many linear feet of tubing will be required.


                              Special Offers: See the latest Miller deals and promotions.