View Single Post
  #18  
Old 08-25-2009, 03:34 PM
John Buchtenkirch John Buchtenkirch is offline
MetalShaper of the Month October 2012
 
Join Date: Jul 2009
Location: Glen Cove, Long Island
Posts: 1,675
Default

Thanks John.

I will have to respectably disagree with your tacking theory.
I feel there should be no hurry here. The faster the parts are tacked together, the more time will be required to peen them flush prior to welding.

In the case of my foot pedal ,I don't use one. It would drive me crazy as I zip around with the TIG torch in my hand.

The machine I use at home is a strike start. Simple really. Find somewhere that the seam is touching.
Hit it exactly on the seam at any angle with the cup touching or not and lift up for a brief second and you have a tack. I tack this way with the same amperage as I weld with.

If the fit is not perfect, tack anywhere that is touching and worry about gaps after the 2 pieces are firmly together.

Pugsy, I have to admit I’m not familiar with a “strike start welder” but if you can do fast tacks (as fast as a mig) without using a rod it sounds fine. I don’t quite understand your comment about peening the tacks flush, when I’m done with my fusion tacks they are just about ready to weld without hammering. I usually run a 3” pneumatic grinder over them just to knock the edges off the tacks and in my case (old eyes) I scribe across them so I can follow the weld line, a step younger guys don’t need. It truly takes me less than 4 or 5 minutes to prepare 3 or 4 feet to weld. On curved parts like that you should just be able to run a fast continues weld with no problem. The idea of welding a little bit, hammering the weld and then welding a bit more is left over from the hammer welding days and in my view neutralizes the speed of the tig. If you run a fast continues tig weld which almost ends up being a fusion weld you should have a smaller HAZ and minimal bead build up which should require less planishing or peening anyway. I just don’t know if the strike start welder is capable not having used one myself ? Anyway you are doing fine work there, I surely wasn’t knocking it, just trying to turn you onto some ideas that might save you a bunch of time . ~ John Buchtenkirch
Reply With Quote