Paint crack or frame?
 

Hey all,

Just noticed a hairline mark, not sure if it's the paint or the frame. There is the main mark then a gap before a second one of similar size. The fram is Alu and the mark is small but it's by the weld line.

imgur c om/gallery/LU7rDB1
Mark

OP's pic...

https://i.imgur.com/7sm0WG1_d.webp?m...fidelity=grand

I'd just think it a scratch in the paint.

You can and probably should watch it for a while to see if it want's to become anything.

If you get yourself a loop magnifier then you can look at it in 3x or more magnification and maybe tell for sure if its a crack or not.

Thanks for posting my pic. A couple of guys have done that for me, much appreciated :)

My vote is it's just fine.

To ramp up production it's pretty common to weld a bit hot so they can weld fast with full penetration. I see new bikes come out of the box with marks like this all the time. A crack wouldn't have a smooth film of paint over it.

FWIW I can't tell if your bike is a Giant or a Specialized. (IME: Specialized has a Praxis bottom bracket/crankset, Giant has a Prowheel.) In either case either one of them are the worst offenders with the hurried & hot weld jobs. A crack, if one were to start, would start at the joint of the exposed end of the down tube there where we can see the cables exit, & not in the middle of the contiguous weld area along the shell.

In your case, it is likely someone was a bit light with the brush grinding out all the slag before sending the frame off to paint.

To add to base2's good summary IME you are well ahead in even noticing it, will no doubt keep an eye on it and if it gets to bugging you you could strip those spots, confirm and re-coat easily.

look at it magnified

I don't think I have ever examined a bike closely enough to notice such a thing...And I've not yet died from a horrific frame failure.

I have broken 3 drop outs, two crank arms, and one bottom bracket to down tube connection and have yet to crash or get injured from it. Keep riding until it fails, if ever it fails.
For the record, Giant is a huge manufacturing company and makes tons of frames with lots of names on them. Specialized is owned by Merida, a manufacturer of frames, and they also build bunches and bunches of frames with many names on them. To single out one or the other as a worst offender is to dismiss all of the name brands their frames wear. What this means is that all of the mass-produced frames have many shared characteristics, and you will unlikely find a perfectly manufactured one.

Apologies for derailing the thread briefly, but wanted to follow up on the bolded above. I had never thought about this but got curious and did a few quick reads. I see that Merida purchased a minority share (49%) in 2001 but didn't see anything indicating it had increased that share to become a majority owner. If you have any other links/stories greatly appreciated. Always curious to read about the innerworkings of bike companies. Thanks!

Just adding my voice to the chorus. To me, that looks like a scratch. Not only is it not in a place I'd suspect of being high-stress, it also looks like it has shiny metal at the bottom. A crack wouldn't. Just as a test, have a friend watch it as you push down on that pedal. A crack would widen, a scratch won't.

Or maybe you did, and this is Hell.

You've lurked the political forum huh?