Titanium weld - good or bad?
 

Dear frame building experts,

Hopefully this is the right section of the forum to ask. If not - let me know!

I just got this Tempest titanium frame that I am about to build up. The welding looks well done all together, but to my surprise I found discoloration on the inside of the head tube at the down tube joint.

Can anyone with good knowledge in bike frame titanium welding tell me if this is something to worry about? The surface is slightly rugged at the discoloration.

https://preview.ibb.co/hDogO6/unnamed_1.jpg
https://preview.ibb.co/hAdsVm/unnamed_2.jpg
https://preview.ibb.co/kKWPbR/unnamed.jpg

If the worst happened, a crack, what's the warranty say? Andy

There is a 5 year warranty on the frame, but I'm more worried about hurting myself. If this actually is a faulty frame from the factory I'm pretty confident I can get a new one.

just monitor for cracks, it's not going to let go all at once. I'm not an expert, but it seems the bluing means that it was exposed to air while hot. I wonder if they cheapened out on the post-weld purge? The roughness is penetration. I think I would be a little more worried that they didn't weld the whole dt/ht interface.

Thank both you for your time. I finally got an answer from the vendor and maker, stating there is nothing to worry about. Better safe then sorry :)
Will keep an eye of it though, as you said Unterhausen.

Not your work ?, they used a inert gas feed into the inside of the tube, Right?