Any tips for telling whether a crack is the paint or metal?

[LikeClockwork]

Re:

It's an old steel Fire Mountain, Dyna...

Must get a proper mag glass though, as you say makes a lot of things easier to see! Picked up something else this afternoon off ebay, so it's eased the pain a little, this can be a wall hanger while I think about what to do with it next....

 

[dyna-ti]

Steel is cool, and thank god its easily welded

I volunteered with a bike project years ago called common wheel(known comically as 'common neil' due to a chap who works there)
One of the projects was run by an engineer with a artistic flair who was always building weird cobbled together bikes. Double frame welded one on the other, huge long chopper like forks kind of thing

I was looking at some of the builds and remarked(in good taste) that the welding was a bit Dogs Baw ( a technical term) and was that strong enough for a 7' long rigid fork leg :shock:
I got the professional engineer look went on to say welding even tacking is very very strong.

Go buy yourself a lidl arc welder and put a couple of 'tacks' on it and i reckon from an amateurs point of view it would be fine to ride, hammer etc.

 

[LikeClockwork]

Re:

Having calmed down a bit and with nothing to do this arvo, I'm going to have a real proper look at it again and remove as much paint as I can from around said joins. Could do with some Nitromors or some such but there you go, haven't got anything, though I will rummage in my landlady's stuff (ahem) as she has a lot of tins of paint, etc, so there might be something there....

Otherwise, and assuming it is cracked, I had already started to think about making it into a long term project (another one...) and having a go at welding, though perhaps with someone else's gear while they keep a careful watch, then I could always add a little more or use artistic licence myself... I'm also keen to give it a custom paint job at some point, by my own fair hand....

In the meantime, I'll try and get some pics of it. The reason I was so keen on this frame was it's had track ends added at some point, which is something I've always wanted to do to a Kona but it costs a fortune which I haven't got, and this frame was fairly cheap already done....needs a respray which is just as well....

 

[LikeClockwork]

Re:

OK, here he is and here's the damage, what do others think....? :?

 

[elite504]

I was just about to reply to this, then I saw the pictures, that is defo not a good structural joint. If you want to have a go at torchwork yourself, try learning to braze, and run a nice wide brass fillet over this section. It should help a lot. It might not be the best-best given the short tube butts and heat affected zone, but as it it, it's the best chance an ameture will have at saving the frame if you want to DIY.

For future reference, if you get the paint off, run a "dye penetrant" test with an aerosol tester such as Magnaflux, that'll show the cracks pretty easily. Search on line, you should find loads of info on magnaflux. Bit less aggro than trying for an x-ray or ultrasonic test.

 

[LikeClockwork]

Re:

Ah OK, that's what I thought, but thanks for the comprehensive reply...hoping I won't be buying any more cracked frames, and ordinarily this one would have been going straight back, but having bought it off someone who's left the country that's tricky!

One to put down to experience I think. A further nail in it's coffin was the fact I've just measured it - having been sold it as a 16", turns out it's a 17", making the headtube 110mm rather than 90mm, so the P2's I had been saving for it won't fit anyway :facepalm:

 

[LikeClockwork]

Re:

Anybody want this as a wall hanger, or for the single speed drop outs? Mind you even they are a bit 'pushed in' on one side, i.e., you'd have to open the one out a little to get a wheel in.

Practice your brazing or welding on it?

PM me and I'll work out the cost of postage, wouldn't be much through work...

 

[66 triumph daytona]

Re:

Looks like undercut to me-where excessive heat or too slow a pass was applied by the welder and has dug in too deep.Its common enough.Its likely that there may be no structural issue.

 

[LikeClockwork]

Re:

Not sure I'd want to risk now thought to be honest, and still not convinced there isn't an issue around the seat stays too. You know what it's like when you've lost your confidence in something....! :facepalm:

 

[Ritz]

That looks likes an undercut weld to me , repairable if you have a fabricator friend and the weld width is not too great.

Don't want to ring alarm bells but I had a Kona Lave Dome fail in the 90's at the head tube, hit a bump and the forks just folded due to the head tube weld fail.

I still ride Kona's though !