High carbon steel welding

admin

Any tricks to weld on high carbon steel such as a tap? I need to cut one in half, use and use half of the tap to start a hole, and the chopped off half to finish some threads. Its tapping cast iron so I dont think strength is THAT important. I could always machine it square but if I can just weld on it that works.HTP Invertig 201Lincoln Idealarc SP250Miller 180 AC StickBy farmall:They should have held the seagull closer to the work, squeezing evenly for best deposition.
Reply:Some preheat and post heat might be needed. --Gol'
Reply:Anything else besides that? COuld I just mig it? Tig?HTP Invertig 201Lincoln Idealarc SP250Miller 180 AC StickBy farmall:They should have held the seagull closer to the work, squeezing evenly for best deposition.
Reply:Good luck......Taps are hard and brittle. Any cutting or welding is going to change that.If you do it, I would like to see it.  DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:perhaps a connection using a drilled hole in the tap would be a better alternative
Reply:no matter what you do, good luck. like David said, taps are brittle and break easily if not handled properly. if you weld it, you would be putting a lot of heat into a very small part, with a high amount of surface area, which will probably warp pretty easily. also, how are you sure it is High Carbon Steel? even if it says so on the package, WHICH high-carbon steel is it? is it maybe a cobalt steel?even if it is just cast iron that you are tapping, i would be willing to bet that a warped tap would not give you the threads you need, especially if it is a fine thread. check out MSC Industrial Supply, J&L Industrial Supply, and/or some other machine tool supplier. i bet you can find a well-priced tap, shaped and sized like you need for the task at hand.Later,Andy
Reply:Me, i would anneal it first,then weld it,then harden it Victor SuperRanger O/A                                         Solar migLincoln Powermig 140Southbend 9in lathe350# kohlswa anvilMiller Maxstar 150 stl etc....
Reply:I have braised on larger taps with some success. They loose some of the hardness, but for chasing threads or cleaning out holes it can work.  Jimmy
Reply:It is probably O1 tool steel. If you get it hotter than a about 350 degrees you will loose the temper and make it soft. You could submerge the tap into a potato and weld it up really quick and then cool it off quickly. The potato will keep the cutting edges cool during a quick weld but it will not do so for long. If the steel turns blue, it is too soft to cut any metal. The TAP is probably in the hardness range of 65-70 (Like a file).You could suspend it in transmission fluid but then you have to worry about getting to the oils flash point and starting it on fire, a potato is probably a better bet.How are you going to cut it without getting it hot?
Reply:We've welded loads of taps, esp when you need to get into hard to reach places, with a lenght of rod on the end, or just don't want to have a holder taken up on a tap you use a lot. SO have welded a "tee" bar cross the endSure they've broken, but never at the weld, usually because of poor cutting technique, or old wornout tap.
Reply:I have seen something similar to Bob's trick used before on things like taps on the web somewhere.  What I saw was a jig that held the cutting part (or, whatever you want to stay hard) partially submerged in water...the potato serves the same purpose...I wish I could remember the website.  I am sure you are reducing the hardness of part of it, but I guess if it is more about access than max hardness for you then it might work fine.Smithboy...if it ain't broke, you ain't tryin'.
Reply:You must be trying to tap a blind hole all the way down, right? What you really need is a taper tap to start  the hole and a bottoming tap to finish. If you're only going to be using this tap once in your life Just grind the tip off of a taper tap once you've started the hole. Grind a little bit at a time and stop to dip in it water to cool the tap and repeat. Dont't let the tap get hot enough to start turning blue.
Reply:my bad. misread the question
Reply:Just get a bottoming tap, then you can do this any time you  need. It won't cost you any more than replacing the tap you are fixing to ruin.The difference between art and craft is the quality of the workmanship. I am an artist.
Reply:I forgot about this post, I read the title and though hey thought sounds interesting.. WHat a minute!! I couldnt find any 11.25" bottoming pipe taps, all I find was "limited clearance" ones. What I ended up doing was giving the tap to my machinist because he had one and I gave him mine to chop on the chop saw so hes got a set to tap engine blocks if he ever needs to. Sorry HTP Invertig 201Lincoln Idealarc SP250Miller 180 AC StickBy farmall:They should have held the seagull closer to the work, squeezing evenly for best deposition.