Droch Stàilinn. Attempt to save a scottie.

[Nabeaquam]

I have successfully straightened at least 4 rear triangles with a simple homemade jig. Cheap bike tubing doesn't spring back as well as good road bike tubing. The steel has a memory and almost always returns to it‘s original position. You have to bend it back further than it was originally for it to spring straight so going slow is the key. Spreading the force over a distance with a hardwood board on the bent part of the frame prevents dents. The first rear triangle I straightened was on a French road bicycle in the mid 1970s. Here is a crude diagram that shows my concept.

 

[Woz]

....me and @Guinessisgoodforyou will be stocking up on sphincter wipes, pop-corn, and lots of drink, and watching from the Bikewrenchers inn.

You're off to a good start - you masochists and lunatics have found each other.

 

[Guinessisgoodforyou]

Should we have a whip round to help cover the dentist bill? I'm going with adult nappies for this

 

[Mickeyspinn]

....me and @Guinessisgoodforyou will be stocking up on sphincter wipes, pop-corn, and lots of drink, and watching from the Bikewrenchers inn.

You're off to a good start - you masochists and lunatics have found each other.

Yes a drink in hand will soften the blow....even from the barstool that could hurt!
Frame I think is saveable...fork hmmm I think I'd bend it into a hetchins curly wurly special style fork and make that lamp ...where's that pic of the balloon gone again......

 

[M_Chavez]

@Nabeaquam
He's Droch Stàilinn. Scottie's just a generic term for a Scot bike.

The rear triangle stays are fine, it's just that the entire triangle is skewed sideways by about 2mm measured at the seat tube, so about 4mm at dropouts. Will be a mk1 eyeball and a floorboard job. I will most likely only move the "inward" stay which will expand the OLD to take a modern hub at the same time. No point bending the outward stay back in to make the hub fitting awkward. Let it stay where it wants to be.

But thank you for the jig details - I saw your report on using it for the Victorian. Impressive!

I hope the sphincter crowd have replaced all their [inherently dangerous] DTs with STIs.

 

[Nabeaquam]

@Nabeaquam
He's Droch Stàilinn. Scottie's just a generic term for a Scot bike.

The rear triangle stays are fine, it's just that the entire triangle is skewed sideways by about 2mm measured at the seat tube, so about 4mm at dropouts. Will be a mk1 eyeball and a floorboard job. I will most likely only move the "inward" stay which will expand the OLD to take a modern hub at the same time. No point bending the outward stay back in to make the hub fitting awkward. Let it stay where it wants to be.

But thank you for the jig details - I saw your report on using it for the Victorian. Impressive!

I hope the sphincter crowd have replaced all their [inherently dangerous] DTs with STIs.

My jig will do that, it will move one side, just depends what you want it to do. I made my victorian press because I couldn’t come up with a deadman. To spread out your stays will require you to move it way way out as it will stubbornly keep springing back to original. You might really have to go way out, just to go a few permanent mm of spread on one side. These high quality frames sometimes crack when spread. Also the brazing can crack. This stuff is incredibly tough. It’s real hard to go from 126 to 130 mm or from 114 to120mm. I don’t think you can spread 126 any further than 130 without breaking it. I’m basing this on my experience with 531, Tange and Columbus. 126 to 130 is hard to do, but I’ve done it.

 

[Imlach]

For the frame itself I'd cover up all the vents, bottle cage holes, seattube, BB, lower headtube and then blow as hard as I could into the top of the headtube, that ought to straighten it out. The fork itself seems fine as it is, if you tilt your head a bit it'll be hardly noticeable.

 

[M_Chavez]

@Nabeaquam I was OK spreading my Bojack from 120 to 130. Clamped the bridges to be safe. That was 531db.
Columbust TSX - that was tough. The stays could take almost my entire body weight leveraged on a floorboard. Unfortunately, the triangle was way off, so had to be corrected or scrapped.

Now, did somebody say "new dropouts"?

 

[Guinessisgoodforyou]

Now, did somebody say "new dropouts"?

I did, and it does need one. It may now take a wheel, but you've straightened a forging cold. Good luck mate it's your bike.

 

[M_Chavez]

Metallurgy is not my background - how do you expect this dropout to fail?

*mumbles something incoherent about throwaway generation*