Need suggestions on welding 2 tubes of different inner dia

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Hi,I have two 4130 tubes that I would like to butt weld together.However, the inner diameters are different.1 @ 1.750 dia .095 wall and 1@ 1.750 dia .035 wall.Can somebody give me some tips or tricks to align and strengthen the joint when I tig weld them together?Thank all in advance,RodSan Francisco
Reply:If you have a lathe it's easy. Just turn down a piece to match the ID's and use it as a backer inside the joint..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:turn the outside diameter of the thicker piece till it will slide into the thinner piece then weld the seam, would give you a stronger joint with less chance of burning a hole in it
Reply:you can take to an exhaust shop and have them crimp one end to slide into the other, I use my hydraulic hose crimper.
Reply:If they actually butt together PERFECTLY then just put a 1/16" 45 degree champher on the heavy wall tube and leave the other one alone..Tack and weld.Aim the torch more at the champhered piece and add filler accordingly..That's what I would do....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Originally Posted by rodjavagive me some tips or tricks to align
Reply:CEP sounds like the simplest and best way to me.If you're worried about the strength of the joint just bevel the ends of both pieces and tig it.panhead201
Reply:Thank you to everybody who chimed in so far. Lots of great advice.1 of the 2 tubes I'm butt welding together is bent 70 degrees and happens to be the.095 wall and the other is straight tube .035 wall. So I won't be able to use my lathe to turn down the .095 tube to fit inside the .035 tube.Grinding might be a option.  Or I can turn some type of coupler on my lathe. Or what Zapster suggested, just bevel the edge of the .095 and tack and weld.What ever I do, I will post the outcome with some pictures.RodSan Francisco
Reply:Not knowing what sort of forces this joint might encounter from your request.... DSW gave the lathe idea of turning a plug to both inner tube sizes...The plug will align the two tubes as well as add a lot of strength... No access to a lathe to turn that plug... insert a short tube inside the smaller inside diameter tube that fits tight and extends into the larger tube and weld the two tubes together plus drill holes thru the outer tubes so you can plug weld each of these holes...that ties things together not only at the joint but at each plug weld too. Not as good as the lathe made plug ,but better than just butt welding the two tubes together if strength is a factor.. I know you can purchase these plugs for the same size tubes...don't know about different size junctions.I'll have to do something similar to a Dune buggy chassis if I ever get around to fixing it...