welding titanium

[Jonny Hotnuts]

I am modifying a Yoshimura titanium header and need to weld on an o2 bung and some hangers.

I had a test piece that I hit with my mig (argon, co2 with solid wire) and it seemed to make a nice bead.
I know this should not be the case.
I was told the header was Ti, it has a gold color and magnets wont stick.

What is going on?

[Harold Bettes]

Jonathan Hot Nuts, 

Maybe it is really stainless. Some stainless is not attracted by magnets, some are. 

Good luck on the project. Since you have seen that it welds nicely, do it to it!

Regards,
HB2

[Dean Los Angeles]

The difficulty in welding is not the weld, but the brittleness after.
Do a google on titanium welding.

The only titanium welding I did was with an electron beam welder in a vacuum and it worked great!

[Rex Schimmer]

I have seen Ti TIG welded and the bead was beautiful but the weld was brittle and easily broken and I have seen it TIG welded in a purged chamber filled with argon and the weld was beautiful and strong. If you want a weld that will hold you need to do it in an inert gas chamber.

Rex

[Stainless1]

JNuts, it is probably stainless.  Titanium will be a little sticky when you melt it to weld.  I did a little Tig welding on the stock Ti GSXR muffler, used some strips cut from another piece of Ti header tubing.  Turned the argon way up and let it post flow over the welds for about 15 seconds.  Welds looked a little ugly, but held up well.  As far as I know you can't Mig a steel or stainless weld on Ti, but ya can on stainless. 

[Peter Jack]

A converted bead blast cabinet works well as an inert gas chamber. You should use separate flow meters for the torch and the cabinet. The best way to accomplish this is to use a manifold on the output side of a good regulator with a couple of flowmeters on the manifold. That way you know the torch is still getting the required amount of argon. The expensive way is to use two cylinders and two flowmeters.

Pete

[narider]

I've heard the '01 Gsxr is titanium, but I welded up a split in mine with my mig(regular old ER70 with no preheat) and later added a tab on it that all welded fine(as good as any stainless or mild pipe anyway).







Todd

[Sumner]

When Phil was over he modified my '02 GSXR-720 headers so we could invert them over the motor.  We seemed to think they were stainless and welded them with the tig with no problems.



He even added regular exhaust tubing in the system below his elbow with the old material on both side of it. 



I hope it holds up, but it's not like it is going to see hundreds of miles of use.

Of course this is OEM headers and JH is talking about aftermarket headers.

c ya,

Sum

more here....

http://purplesagetradingpost.com/sumner/bvillecar-2/construction%20page-91.html

[bvillercr]

I've got a Yosh full exhaust on my dirt bike and the header is stainless.  The Ti might indicate the can.

[Dean Los Angeles]

I watched the F1 race over the weekend. The technical segment was on the exhaust system. Red Bull has three guys full time doing headers! The header is 65 pieces of 20 gage (.035!) and incredibly light. It lasts one race and practice for the next race. New headers every race.

[Rex Schimmer]

F1 headers are made from Inconel which is a real bastard to work with, easy to weld a bastard to cut, and as I remember some of them are even thinner I have heard as thin as .020! and they bend them at around a 2-3 diameter bend radius. The equipment to do this is really something. The company that makes the tubing and bends actually start with flat Inconel sheet, roll it to the diameter required, TIG weld the joint and then bend it. I have worked on CNC tube benders and can tell you to be able to bent 2 inch diameter, .020 wall Inconel tubing with a 2D bend radius it takes a very good bender and some really special tooling.

When I was at Interscope we did some 321 stainless headers for our turbo V6 engines and when we ran them at Daytona we melted the collector that goes into the turbo. Allan Bricky our fabricator had worked at Electromotive on their turbo Datsun motors and suggested that the collector be made from 625 Inconel, so he fabed new collectors from this and what a pain in the ass!! But they never burned out again.

Rex

[malakiblunt]

Hi ive just joned but have experince of welding titanium bike headers, i cut and shut a ehauzt syestem out of yamaha R1 headers. First off i agree with the other posters the yoshi headers must be stainless and not Ti, titanium is a dull gray colour, and mig with steel filler defintly wouldnt work.
How ever if you do want to weld tubes you dont need a argon cabinate, you just have top put bungs in the tubes and flow argon through the tube and its also a good idea to make a trailing hood for your torch to keep the argon on the weld untill it has colued below red heat . It welds beautifully, the problem is it oxidies realy badly at anything above red heat.

Haveing said all that i dindnt do any of the above for my exhaust and it worked well , i just used a bit of cut up header as filler wire and just welded it as if it were steeel.