Is this Ti weld OK or not?
 

It might be an N+ project for a friend. I see that along the weld above and below it is smooth but there is an edge in the center portion. Could that portion be a problem or become one? Or no worries?

Everything looks good in that picture. To be sure can you circle the area you are referring to? Cosmetic imperfections are not uncommon and do not by default represent a flaw.

I agree with BD - looks fine to me.

I was referring to the center outer edge on right side. Thanks.

Cross-sections vary. (I assume you mean what lower image calls the contact angle?)

https://www.researchgate.net/profile...O-2-in-the.png

https://www.researchgate.net/publica...-schematic.png

[oops, double post]

I’m far from an expert, but the weld looks decent to me. The second pass of a double-pass weld is cosmetic, if I’m not mistaken. It’s hard to tell from the photo—it could just the the lighting or the angle—but it looks like the upper part of the weld may be slightly sunken. If thats the case, that would concern me more than the “edge” that you are referring to.

https://photos.smugmug.com/photos/i-...sDSMLnb-X4.jpg
https://photos.smugmug.com/photos/i-...ZbvqKPP-X4.jpg

Looks good to me

Not the prettiest weld I’ve even seen. If it’s well thru the two connecting tubes I would ride it. I believe the only way to tell is to x-ray it. Could be wrong there.

The weld is not great but the gouges on the vertical tube are more interesting.

Looks like someone was perhaps investigating there?

Looks fine. It's what is happening where the tubes meet each other that is more critical.
How is the rest of the frame, price and is it from a well established manufacturer. I'd base the decision more on that than one specific cosmetic spot. And it's just your friend,not family.:)

someone used a file on the tube, likely for cosmetic reasons. Which possibly isn't that great. The weld looks okay to me, seen worse from respected builders.

If you want to be sure, find a place that will do a dye penetrant test. First the weld is cleaned and dried, then a red penetrating dye is sprayed then cleaned off, then a white powder is sprayed on that causes any dye to be absorbed into any cracks or pin holes to finally bleed out and reveal a "indication" (red color dots). If it grows into a large spot, then you have a crack. The person doing the test will be able to evaluate the findings. This type of NDT (non destructive testing) is done on aluminum, stainless and titanium welds as well as others. If there is any clear coat then that would need to be removed. Also use a magnifier (5X-10X) to look closer.

Hi
I was a welder many moons ago.
It looks like undercutting
Not enough filler rod
Too much heat
Welding too fast
Even if it was the second pass You still don’t wanna undercut your pipe
Does it look horrible or not rideable no.
Signed
Grumpy old man