Saved from the grave? - Scapin EOS Pro Team (Weld up jobby)

Based on the ziptie jig shot I thought that dropout repair was going to end up much worse than it did. Well done.

Is that Canondale Saeco getting the same treatment? Is it Alu?

Based on the ziptie jig shot I thought that dropout repair was going to end up much worse than it did

Melt-out jig, innit. Lost wax process.

Haha thanks mate. The cable ties were to hold the 10mm nut in the middle!

The Cannondale is a different project. The headtube on it was bent in after previous owner dropped it on the floor without a headset in. All fixed with a car body work hammer and ready to be built as a commuter for a friend :)

Isn't it missing part of the dropout or is it just the hanger that's missing?

Just missing the hanger!

There's a reason none of the manufacturers turned to MIG despite it's simplicity, it's not suitable for thin walled steel tubes especially when the're posh tempered chromoly.

I did wonder.

What do they use to join modern mass-production steel frames like Surlies, All Cities, Pompinos, etc.?

TIG I would guess, I don't know. Problem with MIG is you're melting mild steel wire into a chromoly tube (well one of the problems), with TIG you can choose a more compatible filler material.

Robots

Yeah but what actual welding process?

There was an arc welding system used briefly after the war (I think) that didn't use any filler material, the tubes were pushed together at high pressure and then a high current was passed through them that fused them together at the joints. It never really caught on, I'm guessing the tooling was not versatile enough for the bike industry.

TIG is the only welding process I know of used for bike frames currently. Brass brazing doesn't actually weld, it sticks the tubes together without melting the base metal

I checked and Pompinos are TIGged according to On One.

I'm sure I could look this up but can you TIG weld aluminium at home?

I can't, but with the right machine, welding rods and skill set, someone could.

Minor update - Dremel’led the crack to see how far it goes each way and it’s really not that bad (as far as cracks go). Thank the lord it doesn’t follow into the brazing or round the tube. Totally confused to how the crack even got there..Part of me actually thought for a minute it was just a strange deep scratch?

Paint stripper currently on the forks. Done a bit of searching around to see if it will affect the carbon and it’s mixed feelings but I thought I’d take the chance. Will update soon

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really doesnt look very much like a crack ... id take off a bit more ...

edit. keep looking, impossible to judge without seeing it. seems odd though!¬

Are you sure it doesn’t go into the brazing? I mean, it does look a bit like it goes past it.

I believe this kind of crack could be a result of tube overheat while the frame was manufactured.

Indeed it's very straight...

No more yellow forks! Paint stripper worked a charm. Will be wet and drying these to bring em up to a gleam. Fork crown is shining bright

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I thought paint stripper on carbon was a big no no. Everyone seems to strip forks by hand when they use chemicals on frames

im going with cracked as its a common place to get them-sure it may have travelled in a slightly different orientation but i believe its going to spread around the base of the seat tube and eventually to a leading edge of the down tube. https://plus.google.com/photos/109418883948018097346/album/5383315872552865249/5383315934084599426

From what I’ve read if you use really strong stripper it can (sometimes) get to the resin in the carbon.. in my case I was using a soft-core Diall stripper that I pulled off when the bottom layer (5 damn layers!!!!) of etch primer was showing

Grim. Good thing I’m saving it ;)

I think the post war welding process Dallas refers to is known as flash butt welding. Dayton used it, but their frames had a reputation for breaking - so maybe that's why it didn't catch on.

Oh noos, my precious splatter paint :D. I never sanded back to the bare carbon, just added a layer of primer and three layers of paint on top of that indeed. Fork does fit the frame nicely must say.

Are you going to run something like a Chris King Devolution headset?