Project 2-6 from Hooda-Weld Blowoff valve on intercooler

[hooda]

So, I met a guy that does hop-ups on Honda Tuners as a part time thing. He showed up at my door with the intercooler and blowoff valve shown below. The idea is to weld the blowoff valve directly to the intercooler. I have very little experience with turbos, so any shot I get I take. Eventually I hope to make it part of "what I do", but for now, this is just a favor to a friend that I will call a learning opportunity (ever heard of pro-bono?). Even though the plan here is welding the valve to the intercooler, every other blowoff valve that I've seen personally, has been installed someplace else along the turbo piping. I plan on doing at least one, if not 2 practice welds before I do the actual part. This due to me relatively little experience, plus the fact that it's not my part. I'll probably post one pic on the TIG section of the forum to ask for suggestions as far as starting settings. But as a rough guess, I'm thinking 125 amps, a 3/32 Lanth tungsten, Gas lens with #5 cup. AC balance at 25, Freq at 125-150. Pulse? maybe, but then I'll change the settings to Average out @125 amps, like 200base, 1sec pulse, 50% background/50% on time. Is this close?

[jakeru]

Sweet!

Let's see, off the top, 125 thousandths = 125 amps (roughly.) I'd set mine up easily at 200 amps (the max my machine does) and feather it back as needed with the footpedal. Don't be afraid to stop the weld bead and give it a few seconds to cool down (for heat control) if the work is getting too hot.

Be aware the intercooler will absorb a lot of welding heat (partly because it is designed to transfer heat away!) It's going to take more current than you might otherwise expect.

I'd probably mix in a little helium and use a 1/16" tungsten, but assuming you are using argon, you'll probably want a 3/32" tungsten. 25% EP balance should be fine. If it were me, I'd set 20% to take the heat off my tungsten but we are splitting hairs. AC Frequency? I don't really know, I'm used to nonadjustable 60Hz though. Maybe go 100Hz, but I'm not sure.

I wouldn't use any pulse, but adding some won't really hurt either. Just remember to increase your peak current to compensate for the lower background current you are using (don't let you average current get to low from the pulse settings.)

That's great to hear you are going to practice on some scraps. Don't be too intimidated by them.

Try and keep your gas cup pointing not too far sideways for good gas coverage (it might be tricky in that spot where you weld between the thick mounting tab and the blowoff valve.) Get a good ground on it somewhere (I'd clamp directly to it.) Try and taper off your welding current slowly, to avoid craters.

I'd probably go with 4043 filler rod on this, since the part gets hot.

[hooda]

Well, I got it done, and all I can say is, "Good thing this is a freebie". I bought the adapter ti run my Everlast WP20 torch and water cooler with the 185 micro, and figured with 2 practice pieces prepared, it would be a great time to compare the 185 Micro to the 250EX. So, I go to hook up the torch to the 185, and..I currently have only one outlet to run, so even though the outlet in the back of the 250EX is live with the machine powered down, I need the outlet to power the 185. So, lacking the means to do the true side-by-side comparison, I fired up the 185 with the factory torch and ran a few beads with the 185 anyway. The 195 Micro would have been excellent for this job, but I wanted to possibly use pulse on this anyway (which I did) so I went back to the 250EX for the second practice piece, then went to work on the actual part. Even though I managed to get the pulse dialed in beautifully, and will be using this feature often, it didn't help much when it came to the actual part. The tank on the intercooler was cast, and from the get-go, it was a smutty mess. It seemed like NOTHING wanted to cooperate. I eventually managed to get it done, but not nearly as pretty as I would have liked. below are some photos if the finished weld.

Sorry, but forst tehy didn't make it into the post, now they made it twice!! The guy came and picked it up, and couldn't have been happier. These pics seem to add a little bit more ugly than it is in person.

[charger891]

Hooda,where`s the pics??