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Discussion Starter · #1 ·
Posting here as I figure the frame builder community would have the best knowledge/experience with this.

Background...
New frame with around 10 rides all North Shore North Vancouver, 1-4 hours.
Titanium - made overseas.
Paragon dropouts.
Ridden single speed.

What are these lines near the welds...? They're tripping me out!
Thanks in advance.
*edit they're both on the seat stay and chain stay
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The last picture is the “line” I would be concerned about. That looks markedly different than the other, to me.
 

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Is there anything to them? Can you feel anything when you run your fingernail over?
My guess is they’re marks from the tube block, or clamp they use when mitering for for the dropouts. There’s nothing else I can think of that would leave such a uniform straight line.


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Discussion Starter · #5 ·
Is there anything to them? Can you feel anything when you run your fingernail over?
My guess is they're marks from the tube block, or clamp they use when mitering for for the dropouts. There's nothing else I can think of that would leave such a uniform straight line.

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I can definitely feel them. They are very uniform. The last image with the 'line' closest to the weld is the most pronounced. Thanks Whit, appreciate the input.

Almost certainly from clamping the tubes. I wouldn't stress about it.

-Walt
Thanks Walt. After hammering on the bike you built for me in 2012 (which is still going strong!) it was time for an update. I fell for the lust of ti (tai, chi) at a 'good' price. I should've just got another one of yours. Cheers, thanks for the input.
 

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Do they feel like they step down just a tiny bit to the weld side of the line? I wonder if they stick the tubes in the lathe and just turn a few thou off to get to clean titanium instead of abrasives and cleaning agents.

That's what they look like to me, but that'd be an odd way of doing things.
 

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Do they feel like they step down just a tiny bit to the weld side of the line? I wonder if they stick the tubes in the lathe and just turn a few thou off to get to clean titanium instead of abrasives and cleaning agents.

That's what they look like to me, but that'd be an odd way of doing things.
Agree. The tubes do seem to step down in diameter by a fraction.

Likely to be harmless though.

Eric
 

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Discussion Starter · #9 ·
If they keep bugging you try polishing down with some scotch brite or higher grit emery cloth. If they don't disappear I'd be surprised.

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I gave two of the tubes a little 2000 grit, if anything they're perhaps a bit more visible.

Agree. The tubes do seem to step down in diameter by a fraction.

Likely to be harmless though.

Eric
It's hard for me to tell by fingernail if they step down. I did mark two of the more pronounced lines at their ends with a sharpie. I'm just gonna ride it as I normally would.

Thanks for all the input guys, appreciate the time.
 
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