custom wastegate linkage (stainless steel TIG welding) jakeru's #13

[jakeru]

I fabricated a custom waste linkage for a hybrid turbocharger (large compressor wheel, small turbine wheel) in stainless steel.

I probably had more time in cutting and grinding of the pieces to fit just right (maybe 20 minutes) than I did in the actual welding (10-15 minutes.) I used 304 stainless rod, plus the cut apart pieces of the original wastegate linkage, (which may have been nickel plated steel of some sort, as it was magnetic.)

I tack welded the linkage with it installed on the turbo (using the welder's finger / third hand for grounding) and actually held the piece with my left hand, as I zapped the first tack autogenously right TIG torch (and plenty of current) in my right hand. It worked like a charm!


Then after getting the second tack weld on there, I removed the linkage and welded it up on the benchtop.

I was going for some rainbow coloration in the weld beads, for a fun and kind of a neat "custom welded" look. And I think it turned out that way pretty much. I used a #6 gas lens with about 12 cfh argon. To get the look, I would purposely pull the torch away during the later stages of post-flow. If you held the post flow on there too long, you would have a silver spot where the weld ended. If the heat was just right when you pulled away the torch during post-flow, the area turns a pretty color. (Actually, I've noticed the "oxidation film colors" are actually inverted rainbow colors; the same colors one sees when looking at a thin oil film/slick floating on water.)

Here is the completed product after being installed back on the turbo:


I used 1/16" 309LSi for the filler rod. 1/16" tungsten with fairly sharp tip (small flat in the end). Low frequency pulsing about 1.5 pulses per second, 60% pulse duty, and 60% background. Footpedal for current control. (Turned way up quite a bit for the first tack welds, then turned down to about 2/3rds of tack weld setting for the full welding.)

Before I welded this, I was welding some mild steel on another project and was having problems on arc starting (arc would try to start back up near the collet body, before moving down to tungsten tip.) For this project I had all of the shielding gas flow related parameters the same, the only adjustment I made was a slight increase in pre-flow. And it was only a very small change in the pre-flow setting... like increased from .5 second to .6 second. It however made all the difference in helping the arc start smoothly.

[Legacyartist247]

Looks beefy! You might considered titanium next time if you like funky blue colors.... titaniums been known to do so.*****

[scootarida1]

That looks sweet, how much boost are you planning on running and what is the turbo going on?

[jakeru]

I've got no plans for it; except for just wanting it out out my shop, and I decided to make it functional before putting it up for sale. At one point I was considering importing turbos as a side business, and this was one of the samples I got. Its part number matched perfectly what I ordered, but the rest of the turbo was completely different and not what I expected.

I figured it might be actually marketable now that the wastegate is actually functional (no longer just a "kit of parts", as it was when I received it.)

Interested in it? Contact me via IM; I'm open to offers. (Save a bundle over buying a name brand turbo!)

Also, I've got one other new turbo "sample" that needs to go (will be selling it as well); it's smaller than this one. So if anyone is looking for a turbo for their project, let me know! Thanks.

[scootarida1]

Sorry I dont want it i just recently purchased a Borg Warner Turbo for my car but maybe someone else on here will want it, good luck and nice fabrication