titanium welding tips

[ryanjones2150]

The subject of this post is for future searches and hopefully we can have some good advice from those with experience in this stuff...

Thanks to BH, I got a really nice selection of practice pieces for welding titanium. What better time to practice than on a holiday when you actually have some time...

The attached pictures are my first ever titanium tig weld. In the first picture, I was really hot, with a probably too big a tungsten. Started with the machine set to 220amps, not knowing how much juice titanium would need. Turns out, not much. In the second picture you can see I tighten things up quite a bit. Probably cooked the base metal though, but all in all...I like it. I really liked making this weld. It just flows nice. The last weld had the machine set to DC, 120amps and not even close to full pedal with a 1/8" tungsten dressed way down to very sharp point, the likes of a 1/16" tungsten.

Share your thoughts please...

[Noel]

Ryan, My experience stems from having attended the Advanced GTAW at Lincoln. As you probably discovered, and for those that haven't, it's a different metal to weld indeed. It likes shielding, and after purge till it cools. Trailing cups are standard as well back purging. Not unusual to have in done in a chamber. As you've probably discovered, torch angle, rod location and how you wick rather then dip the puddle. An interesting metal to weld.

I have more I could mail you if your interested.

https://www.millerwelds.com/resources/article-library/titanium-101-best-tig-gta-welding-practices

One thing they stress is color as an indicator of contamination. It should come out looking with out color as the color indicates oxidation has occurred.

[ryanjones2150]

I didn't back shield it, had it clamped to some aluminum and the back side looks ok. Used a #8 gas lense flowing around 20cfh (I usually run around 15 but I wanted to try and get some back shielding) and only went about two inches at a time to try and keep some back shielding. I got a lot of blues but some straw and silver in there, so not bad for the first shot.

The tig wire is very thin and came in coils, so I figure I'll do better next time getting it straight-ish. That thin of wire is tough to feed with the gloves hand, so I might use a thinner glove for my feeding hand.

I also did very little prep, only cleaned everything with an acetone wipe down, including the wire.

[Ltbadd]

I have done a fair amount of Ti TIG welding, both in and out of a chamber, on production parts the prep is everything, well.. you can find all this info on the web.
It is indeed a fun (different) material to mess with.

Just curious, who is BH that supplied your material?

[ryanjones2150]

Our very own burnthands....he was very generous in providing me some test materials.

I've been sitting here around the fire reading up on titanium welding. It's very unlikely I will have any titanium jobs roll into the shop, but now that I've tried it, I want to be good-ish at it, just in case. I'll probably consider building my own stuff out of Ti if I can get some good deals on materials.

[OscarJr]

I've played with titanium for fun. Even then, from all the research I've done (including reading white papers on welding Ti), cleanliness is everything. Even the oil on hands contaminates a "clean" part. If you're going to take it serious, you need clean cotton gloves to handle it, titanium dedicated tools/brushes. It has even lower thermal conductivity than SS, so if you're not welding it in an argon chamber, you need very short runs, large amounts of shielding (1"+ diameter cups are ideal and provide the largest buffer), and any and all the heat-sinking ability you can. Backing flat parts helps, on flat parts. On round parts, I've found flat copper braided wrapped in multiple layers greatly aids in wicking away heat. Anything and everything that can wick heat away and keep oxygen from the weld bead will help.

(prior to putting on cotton gloves and cleaning the tube )

[Willvis]

I haven't got a chance to weld it but I can tell you that a #8 cup is way to small. I would use at least a #12 cup and even thats probably too small. The other guy said a 1" cup so that would be a #16. Trailing shields are pretty common as well.

[ryanjones2150]

I actually just got a #16 cup in the other day for some stainless I'm about to get on. I used the #8 because that's what was on the torch already.

[Burnt hands]

Ryan,

Glad you got the box of ti scrap and are having fum playing.

Look for more goodies and some details on the samples.

After reading the posts and seeing the photos from other members,

I'll just hide under a rock for a while.

[Burnt hands]

Ryan,

Here are some welds I did using the same 1" wide pieces you have.

The square piece used .035" filler wire while the triangular pieces did not.
Just ran the torch along the joint for them.

Easy to see how just a little variation in travel speed shows up.

45 amps - no pulsing - 1/16" 2% thorium - 9-12 CFH gas flow -
1 sec pre-flow - 15 sec post-flow.
No back purge or trailing shield.
Tig torch is an Airco H16 air cooled with a 1/2" ID nozzle and no gas lens.
No weld chamber - just my weld table with no drafts hopefully.
I try to do my best with my existing equipment but the limiting factor is me.

Still got colors in the bead which means the welds are not acceptable per AWS standards.

They should be silver in color.

Hope this helps.

[ryanjones2150]

Those welds look good to me. Looks like you only have some blues at the very ends, and very little of that even. I'm pretty sure those are acceptable unless it's in the space shuttle.

What did you do to prep the metal? Only thing I did so far was wipe it down with acetone. Next time I get to the LWS I'll get a new brush and file for just titanium.

I didn't stick that #16 cup yet, I have some other work to do. If that stainless job I'm waiting on ever shows up, then I'll switch it.

[pat h]

Ryan, My experience stems from having attended the Advanced GTAW at Lincoln. As you probably discovered, and for those that haven't, it's a different metal to weld indeed. It likes shielding, and after purge till it cools. Trailing cups are standard as well back purging. Not unusual to have in done in a chamber. As you've probably discovered, torch angle, rod location and how you wick rather then dip the puddle. An interesting metal to weld.

I have more I could mail you if your interested.

https://www.millerwelds.com/resources/article-library/titanium-101-best-tig-gta-welding-practices

One thing they stress is color as an indicator of contamination. It should come out looking with out color as the color indicates oxidation has occurred.

Pretty good summary of what I've heard over the years, I've never welded it never needed to, just what I've heard from ua instructors, grain of salt

[Noel]

Went digging out samples I'd done and with permission taken home. Fronts and backs same position for comparing. These were done on a purge block, and if memory serve's me, trailing cups were used. I also recall something about grain growth issues/problems with excessive heats, fast travel speeds. While not clear, I seem to recall a low melting temperature and excellent conduction? Tight arc. Long arc lengths make it too wet, harder to control. and 90 degrees +/- to control size, puddle elongation and avoiding excessive preheating/ melting of the filler. No drops hanging kind of end when brought back from a dab, and not to far to pull it from the shielding. One's need / ability to feed rod consistently becomes apparent.

1/16" filler, 3/32"" 2% thoriated, 16 gauge material. And enough rod to one day try again?

[Burnt hands]

Ryan,

The square piece had only an acetone wipe while the triangular ones got a
sandpaper and scotchbrite cleaning along with acetone.

Here is a model I made for an architecture show.
The base is 6 7/8" in diameter for a sense of scale.
Hard part was the research for dimensions of the real thing.
Then lots of cutting and grinding to make the model proportional.

[tarry99]

Welding it is a whole new learning curve............but wait tell you try to cut or machine it with conventional knowledge........