Welding Tips and Tricks

Well after months of practice, swearing and maybe a few cries I have finished my first titanium part for a customer. I know my tie-ins need work, but they have come a long way. The piece is a 3" down pipe for a Nissan Skyline GTR. After welding this up I had to do some aluminum welding right after an oh boy has my skill changed. Titanium forces me to be so focused, clean and repetitive it was a breeze going back to aluminum. I am open to any constructive criticism.

Did you get a good purge? I'd like to know what gas lens you used? Has to be difficult, I assume you would weld and then let it cool, must have taken awhile

LtBadd wrote:Did you get a good purge? I'd like to know what gas lens you used? Has to be difficult, I assume you would weld and then let it cool, must have taken awhile

When I did practice pieces without heat tinting them the purge was great. I have my purge bottle flow meter set so the ball is just floating. The colours on the inside only happened after I heat tinted the parts first. I was using a SPW # 20 for this one. I hued the Arc Zone monster cups in the past. The #20 cup has better coverage than the Monster #24.

Did you do all of the coloring after welding?

zank wrote:Did you do all of the coloring after welding?

To start I did but I came to the conclusion that heating the pie cuts first was hindering my fit up so I had to redo one of the sections again.

My concern is that all of the contamination from heat tinting gets dissolved into puddle and surrounding HAZ. That's why it appears the tint "disappears" from the weld area. The contamination is going into the interstitial spaces of the crystal and the surface appears "clean".

I know that there are norms for every industry. And I know people like this look in exhaust applications, and it's the norm. Is it not acceptable in your industry to let the coloring occur naturally? I would think the engine vibration would make it desirable to do everything by the book to have as strong a weldment as possible. But I am a worrier.

zank wrote:My concern is that all of the contamination from heat tinting gets dissolved into puddle and surrounding HAZ. That's why it appears the tint "disappears" from the weld area. The contamination is going into the interstitial spaces of the crystal and the surface appears "clean".

I know that there are norms for every industry. And I know people like this look in exhaust applications, and it's the norm. Is it not acceptable in your industry to let the coloring occur naturally? I would think the engine vibration would make it desirable to do everything by the book to have as strong a weldment as possible. But I am a worrier.

So basically from what you're saying and what I could find on google is that pretty much every weld on the part will fail because of the application and because there was some form of oxides at the joint when I welded it.

This is what I came across https://app.aws.org/forum/topic_show.pl?tid=18377

Skylineauto wrote:

zank wrote:My concern is that all of the contamination from heat tinting gets dissolved into puddle and surrounding HAZ. That's why it appears the tint "disappears" from the weld area. The contamination is going into the interstitial spaces of the crystal and the surface appears "clean".

I know that there are norms for every industry. And I know people like this look in exhaust applications, and it's the norm. Is it not acceptable in your industry to let the coloring occur naturally? I would think the engine vibration would make it desirable to do everything by the book to have as strong a weldment as possible. But I am a worrier.

So basically from what you're saying and what I could find on google is that pretty much every weld on the part will fail because of the application and because there was some form of oxides at the joint when I welded it.

This is what I came across https://app.aws.org/forum/topic_show.pl?tid=18377

It's not that it will fail, but considering Senario A: part welded with alpha-case oxidation on surface vs Scenario B: part welded without such oxidation, Scenario A will have a much higher risk of failure due to the embrittlement that will occur.

That said, it should be ok, unless the engine is shaking violently all the time, or twitches a lot on gear shifts.

Edit: Hmm, I just re-read the first post and I thought it was an intake pipe, but it's actually a downpipe that will connect directly to the exhaust. Would I use something like that if it was my car? Maybe. Would I hand that to a customer? Not a chance.

Here is some info on Titanium if you want to look up more technical info:

Titanium info

No, that's not exactly what I'm saying. We can't say for sure if it will fail in your particular application. I just think it's best to do everything as clean and by-the-book as possible when it comes to titanium. It gives you the best shot at making a weldment that will last.

Edit: I would echo Oscar's thoughts.

Originally the plan was to have it done without heat tinting. Normally I do everything by the book as I can. Thank you Oscar for the info. The customer is fully aware that this my first part and knows it might not last as planned. If it does fail at some point the customer will get a new down pipe out of either titanium or stainless free of charge. I am interested in doing inconel for these kinds of applications. Im having a hard time finding a good supplier in Edmonton or Canada. I knew that when titanium has oxidization from the heat of welding it affects the whole thickness of the material, not just the surface. I was not aware that any oxidization would affect the weld. I guess I was naive to think that titanium oxidizing is bad only if it occurs when the material is heated to elevated temperatures during welding.

We all learn as we go. Keep pushing forward!

[quote="Skylineauto" I am interested in doing inconel for these kinds of applications. Im having a hard time finding a good supplier in Edmonton or Canada.[/quote]

You're going to pay an arm, a left, and your left testicle for Inconel from any supplier in North America. Is this your full-time job where you will be supplying this for many, many customers? Or are you doing this as a "side-gig" for a few select individuals? For the former, then you need to establish ties with vendors who stock this on a normal-basis. For the latter, you need to look for suppliers west of the Pacific to save on costs, otherwise you'll end up losing money on jobs, especially if you promise customers that you will re-make the part if it fails for free.

Yes I have my own performance shop. About 65% of my work is fabrication. I have a few customers that understand that it costs money to do things right and are willing to pay if the job requires it. This down pipe was more of a way of getting my name out there.

Edit, The reason Im doing these types of materials is its a void in the market. There are a million people in Edmontom and out of the "speed" shops nobody offers these kinds of services. They offer custom fabrication but they also offer every other service so the skill and expertise in the fabrication area always suffer. The closest would be Chris from Unobtainium Welding whom Im sure we have all seen his work at one point in time. and he is a 3 hour drive away so am trying to capture that market here.

Skylineauto wrote:Yes I have my own performance shop. About 65% of my work is fabrication. I have a few customers that understand that it costs money to do things right and are willing to pay if the job requires it. This down pipe was more of a way of getting my name out there.

Edit, The reason Im doing these types of materials is its a void in the market. There are a million people in Edmontom and out of the "speed" shops nobody offers these kinds of services. They offer custom fabrication but they also offer every other service so the skill and expertise in the fabrication area always suffer. The closest would be Chris from Unobtainium Welding whom Im sure we have all seen his work at one point in time. and he is a 3 hour drive away so am trying to capture that market here.

In that case, I'd say get your hands on the best material you can get, and pass the costs on to the customers. Finding a niche market product skill will definitely pay off if you have the customer base.

Did you make your pie-cuts or did you order them pre-cut? I know there's this one place (or several maybe) that sell them pre-cut. I need to get my hands on some more titanium this summer.

Oscar wrote:Did you make your pie-cuts or did you order them pre-cut? I know there's this one place (or several maybe) that sell them pre-cut. I need to get my hands on some more titanium this summer.

I bought it from Ticon Industries. They seem to have the largest selection of titanium parts for the kind of work I do. The quality is pretty good. Out of about 10 pie cut kits I have purchased from them (50 pieces) three were not usable. There is also Titanium Dynamics, but I have never bought form them yet.. I was able to find a supplier on Alibaba that sold the pie cuts for $5 each. They also had a whole swack of titanium they sold. Hope this helps.

Yup, Ticon seems to be the go-to place for pie-cuts in the US. I need to get my hands on some plate and tubing to hopefully make some cool "structures". Time to break open the piggy bank and get ready to eat mac-n-cheese and ramen noodles for a month, lol.

When doing Ti work, particularly aerospace, I thought the goal is to never have any color at all? At worst, straw yellow is the only acceptable and it must be kept to a minimum? I know it's an exhaust albeit at the hottest part of the engine, but I figure the same rules apply. I'm not judging, just asking/confirming since I know some of our Ti gurus have stepped in and I still have that Ti job to do on the exhaust cosmetic tip soon enough

entity-unknown wrote:When doing Ti work, particularly aerospace, I thought the goal is to never have any color at all? At worst, straw yellow is the only acceptable and it must be kept to a minimum? I know it's an exhaust albeit at the hottest part of the engine, but I figure the same rules apply. I'm not judging, just asking/confirming since I know some of our Ti gurus have stepped in and I still have that Ti job to do on the exhaust cosmetic tip soon enough

"the goal" is always a compromise. You want perfectly silver welds? Better be prepared to spend $800 for a top-of-the-line gas shield, or a $2000+ argon chamber. at bare minimum Of course, in aerospace work cost is not a factor, so companies have all this proper equipment. But for a fabrication business barely starting out with titanium, you have to weigh out the revenue the work brings in vs the cost of implementation of weld shielding equipment/apparatuses.

And then there is that one market of super colorful titanium exhaust tips where customers want oxidation. They may not know it as such, but they know they want the "colors". Go figure.

Never thought about this much as I never have done any titanium but could you buy a cheap Harbor Freight sand blasting cabinet and modify it into a small part welding chamber?

stefuel wrote:Never thought about this much as I never have done any titanium but could you buy a cheap Harbor Freight sand blasting cabinet and modify it into a small part welding chamber?

It could, but it's easier and faster to write a check to CK Worldwide for their collapsible clear plastic purge chamber.

I think there is only a few applications where a fully inert atmosphere is required for titanium welding. During my research I did come across aviation welding where it was done with a large trailing shield and a good back purge with a oxygen monitor. These parts were 100% quality control to the point where the flagged filler rods were kept in a locked storage tube. When the welding was done each filler rod lot number was recorded and the stub ends kept and stored. Like Oscar said, depends wht the end goal is to be. But will disagree about needing expensive cups, or some kind of purge chamber. There a large number of people producing perfect silver welds with perfect penetration with nothing more than a massive cup, good purge and a massive amount of patience.

Skylineauto wrote:But will disagree about needing expensive cups, or some kind of purge chamber. There a large number of people producing perfect silver welds with perfect penetration with nothing more than a massive cup, good purge and a massive amount of patience.

I agree with you, simply because I wasn't specific enough. When you need to hammer out parts fast in a production environment, you can't hang around and wait for the metal to cool on it's own, and active purging becomes a necessity in order to make welds that are longer than you could if you didn't have additional purging. If you're making one-off parts here-and-there with no timeline working at your own pace, then I completely agree that with enough patience to overcome the waiting that parts need to cool off , one can produce very nice welds as a result of multiple short beads that allow for intermittent cooling between bead runs.