Post your best welds!
- those of you posting specs, do you mind posting what welder you were using (even settings) if you know? I know that some of you putting down those killer welds could do it with a tig torch hooked up to a pair of batteries, but I'm still wondering. I have an old synchrowave and I have never been able to get a clear answer to what tungstens I should be using for what, specifically some suggest using it like an inverter on aluminum and others say you need to run pure like an old school transformer (it is a 400# transformer in the box).
- I'm also curious if you guys took classes, did some sort of online thing (watched videos, someone's instructional deal...) or just did it on your own till you got the results you wanted? As I mentioned early on I can do things with a MIG most people can't, but my TIG skills are pretty bad, and I've never really made traction getting them better. I've even considered taking classes at a local college and found that no one that I can find gives just a TIG class... and honestly my stick and gas skills are good enough for what I need and my mig skills are better than what I really need, so I don't particularly want to (nor do I have time to) take a general class that teaches all of them.
The Best V8 Stories One Small Block at Time
This is my latest project - I decided to try my hand at building some double slip merge collectors for my m3 swap project. 1-7/8" to 2.75" merge, which expands out to 3.5" then an anti-reversion back to a 3" vband. It isn't the greatest welding in the world but it's my personal best so far in terms of the fabrication effort involved....still a lot to learn.







Vband flange weld


I did some reading about the vband weld ahead of time to get some insight into managing heat input and hopefully prevent warping, but it still warped pretty bad despite my best efforts. I was able to bump and file it back to being pretty flat though, fortunately, so I think it will still seal. When welding, I clamped the other half of the flange on there and set the whole thing on a big aluminum chill block to help draw the heat out.
As far as weld settings:
-1/16" tungsten sharpened to a fine point
-.045" filler
- about 3/4 pedal with the machine set to 120 amps, 30 hz pulse with 50% on time and 20% background. I used the pulse feature to help keep the arc from wandering over onto the clamp since it was extremely close to the flange.
I'd weld about 1/2" at a time, stop and give it ~10s of postflow to cool it down, then rotate the whole thing around and weld a little on the opposite side to try and spread out the heat. My HAZ isn't that wide so I didn't think I was putting that much heat into it. I left the assembly clamped together until it cooled back down, but when I unclamped it the flange looked like a pringle.
Anybody in here have any tips for a noob on how to prevent warpage when welding a v-band flange?
You had the machine set to 120 amps. There is no need for all that when welding thin stainless. You could likely get by at a little over half that. It would help with your warping issues as well.
BTW, that is an incredible collector build for a beginner. Did you buy everything pre-cut?
You had the machine set to 120 amps. There is no need for all that when welding thin stainless. You could likely get by at a little over half that. It would help with your warping issues as well.
BTW, that is an incredible collector build for a beginner. Did you buy everything pre-cut?
That being said it was obviously too hot and I'm going to try it without pulse and lower amperage so I don't have to camp out as long to get melted. Would you suggest letting it rest to cool at all intermittently? Like giving it a minute or two break every now and then?
And thanks, I built that fixture after I realized it was extremely difficult trying to fit it all up by eye - trying to hit a moving target so to speak. I cut everything myself - they started as 45 degree mandrel bends that I cut in half, then I made a model in solidworks and 3D printed a fixture to position the bends in my chop saw to make the cuts. I cut them a little proud of the reference faces and did fit / final sanding while checking on the fixture. Worked worlds better than my first one that I tried to fit up freehand.





All of the faces serve as a reference for where the cut edges need to be for theoretical fit up. Some attention is required to keep the tube from slipping while cutting but all you have to do is flip the fixture around in the jaws to make your cuts, no careful realignments or thinking necessary.
Lots of gotchas during the process of building this first (successful) one. It's far from perfect but I learned enough to hopefully make the second one better.
I'm going to attempt my first header build and would like to build the collectors as well.
Blown06 and Tig - more than willing to help out however I can. I'll shoot PM's to you both and we'll go from there.
















