Help! Is this a crack, or a manufacturing flaw?

[ForestHill]

Hi, I got this 753 frame off eBay last week, built it up at the weekend and have ridden it a couple of times over not many miles.
Today though, I noticed what looks like a crack at the top of the seat stay. It's hard to tell, but I sanded it back to get a closer look and it seems to have a 'lip'. It's slightly higher at the wheel end, almost like a sleeve has been put on, but it doesn't go all the way round. I thought it may be a paint run at first but it's definitely in the steel.
It's almost perfectly straight and stops at that black dot (sharpie!).
There doesn't seem to be any movement in it in any direction as far as I can tell, and I can only assume it was there when I bought it - I certainly haven't ridden it hard.
Can anyone reassure me that this is just a cosmetic thing, ( I have no idea how it could be) and not a 'contact the eBay seller and ask for at least a partial refund' situation?
Pictures are here
http://imgur.com/a/8kJjc

Cheers.

 

[danson67]

Looks like a crack to me :cry:

Certainly not a plug stay end, you'd be able to see a line of silver...can you trace it round the other side?

Any sign that the frame's dropouts have been spread? It's a bit suspicious that it starts at the bottom of the seatbolt fillet.

All the best,

 

[ForestHill]

I don't know how I'd tell whether they'd been spread, save contacting Proctor and asking what the original spec was. Is there another way? It seems in an odd place, and not near any brazing, making me think it probably is a crack :'(

I've realised it actually looks worse in the picture, and it's probably accumulated a bit of debris from the sandpaper, it's not too bad in real life, which is where my doubt came from. It's also a straight line, with quite a big lip. I've seen a crack in exactly the same place before and that went all the way up to the braze, this one just stops.

It's a bugger, I'm sure the eBay seller didn't notice it - she said she was selling for her father in law. Suspiciously (to me at least), the whole cluster had been sprayed with gold rattlecan paint, making me think that perhaps they were trying to hide the damage. That could just be me being paranoid though!

I've emailed the seller to see what they say about it, and whether they knew it was there. It's a bloody shame, it's a lovely, lovely frame and I'd rather get some money back and pay for a repair than return it.
Fingers crossed the seller sees it the same way!

 

[ForestHill]

Ha, scratch that. I've just had a look from the other side and there's a ~1mm crack where.the stay meets the lug. It must have been hidden by the paint.
Bugger.

 

[Midlife]

Looks like a stress / fatigue failure, ,like the sort of thing that brought down the Comet Mk I .........maybe a touch too hot during manufacture...

Shaun

 

[Jonny69]

Yep looks like a crack to me. Should be easy enough for any competent welder to fix. File the crack to a V so there's somewhere to weld into and then lightly weld. If you can find someone with TIG then it'll be neater because MIG will put a lot of extra metal on and it'll be added work dressing it back. Not a problem though. For that repair I think TIG will put less heat into the metal and thus will be less likely to affect any surrounding metal if it's heat treated.

 

[Robbied196]

Yep looks like a crack to me. Should be easy enough for any competent welder to fix. File the crack to a V so there's somewhere to weld into and then lightly weld. If you can find someone with TIG then it'll be neater because MIG will put a lot of extra metal on and it'll be added work dressing it back. Not a problem though. For that repair I think TIG will put less heat into the metal and thus will be less likely to affect any surrounding metal if it's heat treated.

+1

 

[danson67]

IMHO not so easy to TIG...you can't prep the crack with a V, the stay walls are only 0.6mm thick at the top.

Also, the frame should have been silver soldered (certainly not welded), so any melt or internal flux from the nearby fillet between the stay and seat lug will boil out and contaminate the weld.

753 shouldn't be heated above 40% silver temps, 700Cish. TIG or MIG will take it to 1500C.

All the best,

 

[ForestHill]

Good news! The seller has offered a full refund. I've asked whether I can hold onto the frame as I have hopes of getting it repaired, but I realise that 753 is a bugger to fix, and that the crack is in a terrible place - not shown on the picture but there's a separation where the seat stay meets the seat tube.
Probably not worth it. It definitely wasn't the seller's fault, they obviously didn't realise it was there, I'm just glad I did before I rode it properly!

Thanks for all the help.

Now, anyone got anything to replace it? Something 531c/SLX with eyelets for guards perhaps?

 

[danson67]

That's good news. Always good to sort things amicably.

753 might be a bugger to fix, but as it's silver soldered, both stays and the brake bridge could be replaced pretty easily with something newer (525/631 etc).

As long as the new parts are silver soldered again, rather than brass, there shouldn't be a problem.
About £150 for the repair from Dave Yates, though + paint Not sure what others might charge.

All the best,