[brad_m]

I bought an AC/CD 200amp TIG machine today. I've been using a small 130amp CIG lift arc for a while on stainless steel.
Having never welded alloy before, I figured the best way to learn is to just do it.
So I grabbed an old cast intake manifold and layed down some beads.
At the end of the last bead I accidentally touched the electrode into the weld....

I'd like to begin with getting a good pad weld on this particular intake manifold as there are a series of modifications I want to test on a flow bench. In some places (corners) I will need to build up 3/4 inch of weld.

I've included photo of the settings I used, The A/C balance was at roughly 50%
2.4mm 2% lanth
2.4 rod mm

[Sandow]

I'm not sure a casting is a great thing to learn on. Just too many things going on that can be confusing while getting the hang of it. I'd grab some sheet or bar stock in the thickness you'll be welding and play with dcep on time and stuff like that. Easy to see on mill finished aluminum. Get used to setting amp adequately to puddle quickly and then get good at tampering off to keep your travel speed constant. You'll find that building up thickness with aluminum is pretty easy in general.

-Sandow

[MosquitoMoto]

Jumping in at the deep end, eh?

I agree with Sandow that a manifold is a challenging place to start, but what the heck, I also have a habit of jumping in at the deep end too. The manifold could be made out of an odd alloy, there's the problem that it's likely dirty (although I see you've done some cleaning...) and other stuff besides.

Anyhow, enough of my rambling.

Your amps seem quite low for the part you are welding on. Also, it might be worth starting out with 30% cleaning and cranking up more from there if you need it, 50% is a lot. Finally, after cranking the amps you might try 3.2mm filler to get more material in there. Your beads are certainly not a disaster (except where you dipped) so you are on your way.

I practised for ages on flat plate before I did a build up job on a heavy motorcycle bracket. I wound up the Hz (200 I think?) to focus the arc and then just built up a little at a time until I'd closed the gap.

All the best - post photos!

EDIT: Oh, and at those amps, how long is it taking you to get a puddle going?




Kym

[DLewis0289]

I am with the other guys, cast is not the first choice for beginning practice. But honestly except for the one little boo, boo, for just starting not to shabby at all. Definitely tell you have some TIG experience under your belt. Couple hours of practice you will be on your way and build up will be a breeze after you get the first passes laid down.

[brad_m]

Jumping in at the deep end, eh?


EDIT: Oh, and at those amps, how long is it taking you to get a puddle going?

Kym

Yeah, it was a bit of jump in the deep end and a bit of this is the only bit of alloy I have and I wanted to play with the new toy.

Took 2 or 3 seconds to get a puddle going.
The manifold has been sitting a cleaning bath for a few days and normally the next step is soda blasting and for now the final welding is farmed out. Final product is bellow

I am with the other guys, cast is not the first choice for beginning practice. But honestly except for the one little boo, boo, for just starting not to shabby at all. Definitely tell you have some TIG experience under your belt. Couple hours of practice you will be on your way and build up will be a breeze after you get the first passes laid down.

I've been using my small lift arc for about 12 month doing fusion welds on stainless steel tube. To be honest I find it hard to add filler and get a decent looking weld with stainless. Getting the rod in with alloy seemed easier.
Tacking with lift arc is also very painful and messy.

This is one very early stainless job and some recent stuff.

[MosquitoMoto]

Nice to see some more pics Brad - thanks for sharing.

If you scroll down a few entries in the 'video discussion' section there's a nice series where Jody is welding up a manifold - some aspects of the shape of your part reminded me of it.

Kym

[Oscar]

Overall, the work is not too bad. Automotive hobbyist/enthusiast?

[brad_m]

Overall, the work is not too bad. Automotive hobbyist/enthusiast?

I'm a mechanic and have always had an interest in metal work.
In high school I did an entry level course that covered basic MIG and stick welding, basic Lath and Mill work and basic sheet metal work.
I own my own mechanical workshop and we have branched out into sell 4x4 product and wan't to develop some of our own gear.

[brad_m]

I stopped in and bought AU$50 worth of off cuts and varies sizes and spent some time at my welding table.


A few notes:

I cut the flat bar long enough to force me to work the rod with left hand, I need the practice of feeding the rod.

I still touched a weld with the tungsten a few times.

I'm finding that using enough amps to quickly start a weld puddle means I'm over heating it by the end of the weld. (no foot peddle)

I did some pad build up on some 100x100x10 The start of my welds are dirty and the ends all end up sunken.


I have a some questions:

I was working with 40amps per 1mm of thickness on the 3mm butt welds and varied the amps in both up and down to see what it did. Is 40amp per 1mm a good starting point?

How can I get a clean start to the weld?

How can I reduce the sinking at the end of the weld? The first weld on the 10mm plate was at 175 amps, once there was some heat soak I had to drop back to 120 amps or the weld would flatten out.

[motox]

check out this video
https://www.youtube.com/watch?v=TidFih7Dpus

[DLewis0289]

I don't know Jody personally and gain nothing for saying this. His hands on ability is unquestionable, been welding with multiple processes for many, many years and mastered all of them. The PRODUCTION value is academy award worthy (seriously, not trying to be funny here at all). The camera work, the editing, narration and concise accurate instruction, has and does make me recommend the site to people in lieu of paying tuition at a local junior college or welding school. As an academic and sometimes welding instructor at a junior college you simply cannot provide this on a student by student basis. Simply not enough time in class.

The only time I recommend going to a formal welding school anymore is for commercial diving. And it's not really for the welding but the host of other things that are involved. Wet welding from a welding perspective is not a lot different, dry (habitat) is exactly like normal welding.

My personal opinion is the site content should be licensed and made available as another lab in conjunction with the formal curriculum in welding training programs.

[motox]

d lewis
might i also add that with Jody starting this
site with all his welding expertise included, he also
managed to gather together an incredable
group the varied welding and fabricating
experts. members not afraid to pass on
years of acquired knowledge while leaving
their egos at the door.
i thank Jody and all who contribute the this
wonderful forum.
craig

[brad_m]

I thought it might also be helpful to post the functionality of my machine.

[RamboBaby]

If your machine has an input for a foot peddle then I highly suggest that you get a peddle for it. Aluminum doesn't weld like any other metal because it is so thermally conductive and I can't imagine trying to learn how to weld it without amperage control. It's hard enough to learn how to weld it with a peddle. The stuff is very slow to heat up but then it rapidly overheats. The latter is when you really NEED the peddle but you seem to have figured that out. Other than that you just need to terminate the arc when you see it begin to overheat but that's when you're gonna discover another serious problem with welding aluminum: it's hot short. Craters from rapidly terminated arcs cause aluminum to crack. You can try adding several more jabs into the last ripple of the puddle to stop this but I doubt that you're ever going to be really happy with the results. Peddle pulsing aluminum is almost mandatory in some situations and in others it just leads to a much more beautiful weld.
Brother, if you can afford a peddle and have a connection on your machine for one.......do yourself a favor and spend the cash on it. You'll be glad that you did. You'll see your abilities improve much faster.
Your stainless welds look good. I need to learn how to weld that stuff myself.

Edit: why did you run practice beads on something that you actually planned on using?

[brad_m]

Edit: why did you run practice beads on something that you actually planned on using?

The part I welded on is machined off completely. The picture explains it.
You can see at the back edge that it's not straight and there is a bit missing. For now I need to be able to weld those up and grind them back true.

Future experiments will be filling the top of each runner in and grind some tapper and a bigger entry radius in. and few other things that need better pictures to explain.

If your machine has an input for a foot peddle then I highly suggest that you get a peddle for it. Aluminum doesn't weld like any other metal because it is so thermally conductive and I can't imagine trying to learn how to weld it without amperage control. It's hard enough to learn how to weld it with a peddle. The stuff is very slow to heat up but then it rapidly overheats. The latter is when you really NEED the peddle but you seem to have figured that out. Other than that you just need to terminate the arc when you see it begin to overheat but that's when you're gonna discover another serious problem with welding aluminum: it's hot short. Craters from rapidly terminated arcs cause aluminum to crack. You can try adding several more jabs into the last ripple of the puddle to stop this but I doubt that you're ever going to be really happy with the results. Peddle pulsing aluminum is almost mandatory in some situations and in others it just leads to a much more beautiful weld.
Brother, if you can afford a peddle and have a connection on your machine for one.......do yourself a favor and spend the cash on it. You'll be glad that you did. You'll see your abilities improve much faster.
Your stainless welds look good. I need to learn how to weld that stuff myself.

There is an optional foot pedal for this machine. I am planning on buying it but the machine used up the money I had.
There is also a dial on the torch for amp control but the way I hold the torch I can't get a finger to it and it's overly sensitive as it has full range control from 0 to 200amps. Foot pedal will also let me hold the torch like I could with the other machine, that will steady my hand too.

You've hit on all the issues I was having and Jody's latest video touched on A/C balance, like some of the other guys said I was using to much.