rosefarts

My favorite bike, an early aughts Tallerico has a fork that's a squosh too short. The previous owner did that, as slammed stems were popular for a time. It's a 1" threadless Columbus steel fork with straight legs and a brazed crown, 650g, all steel. Not an easy thing to just go replace. I screwed around with some Chinese carbon forks and am much happier with the steel one.

It's rideable. If I install the stem (low stack height) directly onto the top cup, I get decent attachment but even then, should be 1/4" longer.

Ideally, I'd like to add spacers and raise the stem 3/4" to 1" or so. Subtle but it's actually a big deal for fit.

I've done a kludge with a compression plug. It's ok but I'll end up needing to tighten the headset after every railroad crossing or rough road.

So I talked to a local steel fabrication guy. He seems competent. The ideal would be to insert a 22.2mm pipe into the fork and braze the insert in, as well as a 1" diameter pipe onto the narrow tube sticking out. This should give me that extra length and be solid. I'd prefer pretty high wall thickness on the 22.2mm tube.

This doesn't sound hard. A walk in the park for a fabricator. I'd even be tempted to do it myself but I don't have map gas, flux, or silver solder, so materials alone would probably cost me more than a pro.

Still with me? Finally I have questions.

1. Would the heat from the brazing adversely affect the strength of a steel steerer? This is the best descending bike I've ever had, and 55mph + is always a possibility.

2. If he wrapped the rest of the fork in wet rags, would that suck out enough heat to save the paint? Would it suck out too much heat for a good braze?

3. What should I request he use? Silver solder?

4. For a 3/4" to 1" extension, does it matter if it's not Columbus? Does any steel pipe that matches the internal and external diameter work?

Sorry for the rambling.
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Fissile

Why not just replace the entire tube? Any kind of brazing is likely to fry the paint anyway. New tube, and repaint is what I'd do.

https://framebuildersupply.com/colle.../steerer-tubes

rosefarts

The paint is really good though, with Columbus stickers and a fade.

Fissile

Columbus stickers.

https://velocals.com/columbus/

Fissile

Columbus stickers.

https://velocals.com/columbus/

rosefarts

I'm not convinced but you've got me thinking.

Of course the steerer tube I'd need is sold out. How often do they get new inventory?

Andrew R Stewart 

A really good guy could sleeve the ID and add some tube to extent the steerer without hardly any dog leg happening. This would be done at the top, away from the paint at the crown and not involve the paint at all. One could even incorporate a nut for the compression/preload bolt. But the chance of the extension being off axis is high. This is about as much work as a complete steerer replacement. If i were to do it I would quote as much as a complete fork, painted. Why? Because that's the fall back plan B. Andy

Fissile

Try this place. https://www.cycle-frames.com/STEERER-TUBES/

Fissile

^Troof^

wsteve464

If the longer plug doesn't work cut the steerer near the top, and add extension from part of another steerer tube with an internal sleeve and have it tig welded. If the weld bead is too high you can have it turned on a lathe or file it down. Tig welding will likely not mae the crown ara of the fork hot enough to melt the paint.


1" steerers in stock.
https://www.cycle-frames.com/1-inch-...-NON-THREADED/

rosefarts

This seems like a pretty viable plan B.

I'll probably go to the metal guy, who is more of a hot-rod custom parts type guy on Monday. I'll see what he thinks. If the joint is actually encapsulated within the stem, would a half degree dogleg matter? The bearings would be away from the repaired part.

I may also reach out to the frame builder but seeing as I got this bike used on eBay 3 years ago, and not the original owner, I don't know. Funny thing is, it fits and rides like it was built for me.

If I need to replace the whole steerer, will I also need to replace the crown race fitting? Not the actual race but the thing to allow you to press it on. You're frame builders, you know what I'm talking about.

Will the two extra heat cycles affect the strength of the crown (1 to take it off + 1 for the new one). Will this affect the strength of the fork legs brazed in very near?

Thanks guys, I've already learned a lot.

Andrew R Stewart 

These questions are for the one who does the work. The builder will be the first best one to go to for a few reasons. He should know his method of construction (silver/bronze, pins) and his preferred repair. If he's agreeable use him (or her...). Removing the steerer from the crown might not involve a heat cycle. But crowns are pretty massive compared to tubes. I've recycled a couple, won't do it again because it's a lot of work to look good but have no fears of problems if done well. Andy

bulgie 

Plenty of steerers have been extended by grafting, going back decades. Can be totally reliable. It is both easier and safer than replacing the whole steerer, even aside from the expense which is much less (and no repaint).

Back when steerers were threaded and quill stems had to go down inside, the graft would usually be put about halfway down. You just need the graft to be low enough to clear your "starfangled nut" or whatever you use to preload the headset.

It definitely can be done without any harm to the paint at the crown. TIG welding is faster, less heat input and less chance of paint damage, but it can definitely be done by brazing as well.

If you don't want someone learning on the job, give it to someone who's done lots of them. I know Bernie Mikkelsen in Alameda Calif. has done a zillion of them, maybe give him a call?

I always encourage folks to tell us where they are in the world, especially when asking for frame repair advice -- maybe we can suggest someone who's closer to you.

Caution, about the stub you propose for reinforcing the joint: you say 22.2 mm, but be aware that a lot of threadless steerers are thinner wall for light weight, thus the plug needs to be larger than that. Measure to be sure (Apologies if you already measured).

No, the piece you add doesn't need to be Columbus. Just about any steel will work; it just needs to match the OD and wall thickness. Cut a piece of steerer from a dead fork. Huffy, Schwinn, it pretty much doesn't matter.

Mark B in Seattle

rosefarts

Mark B. Some good ideas.

22.2 is stuck in my head but of course we'll be measuring again before anything is done.

I'll mention welding to him, I only brought up brazing because in my mind, it sounded easier. Like glue but with heat.

For location, Pueblo, Colorado. I can't quite see the steel mill from my house and I don't live on the superfund site, but it's close. Every third business here is "Steel City" this or "Steel City" that. So hopefully some expertise is here.

I'm sure there are frame builders in the Springs or Denver, but if I've got to make the trip, I can just put the whole thing in the mail for someone.

bulgie 

Well, I shouldn't have mentioned Huffy and Schwinn, bad examples because some Schwinns from the '70s and earlier took a smaller quill stem. 0.833" (21.2 mm). Maybe Huffy too -- it's sometimes referred to as "BMX size" though Schwinn used it on all kinds of bikes, like the Varsity. Also, if you have one of the lightweight threadless steerers that are larger than 22.2 mm inside, then that makes it harder to find a crashed donor fork to cannibalize the steerer from. I should have just stopped after "it just needs to match the OD and wall thickness" -- that part is true.

-mb

unterhausen

It's a bit quaint, but Columbus still makes rifled steerers, so they might not be the best choice for a repair.

bulgie 

How so?

• For a graft type repair, the piece you'd be cutting to graft onto the existing steerer would be off the top, well above any rifling, which is only in the butted section.
• For a total steerer replacement, the rifling won't hurt anything. It doesn't really do anything, quite useless IMHO other than branding, but no downsides either.

Well, one theoretical downside: it doesn't work with a dogwood dowel or other reinforcements you might be inclined to stuff up in there. Note, the wood dowel was used in some high-end bikes many decades ago, mostly before 1970. Typically French, but some Italian too -- my '61 Bianchi Specialissima came with one, stock. I doubt the dowel did much for you, but it was claimed that it would hold the fork together long enough to stop safely if the steerer cracked.

Some tandems and MTBs in the Bad Old Days used a standard 1" butted steerer with another piece of steel shoved up at the bottom. The steel reinforcement probably did actually help with strength/reliability, but wouldn't work with a Columbus or other rifled steerer.

Mark B

rosefarts

It's totally smooth inside. If it is rifled, it's not at the proximal end.

Fissile

Schwinn tubes that were used for their 'electro forged' bike frames was pretty thick stuff. The steel was kinda soft but was just the thing for the automated processes used by Schwinn for almost all their domestic bike frames save for the Paramount or fillet brazed models. Even their fillet brazed bikes used some weird sized tubes.

rosefarts

The fork along with a "Huffy Triathlon" as sacrifice has been dropped off.

This is a full fabrication shop but are a pipeworks shop. They found a great piece of pipe with the proper ID. The huffy is the same as my steerer tube. The plan is to tig weld it.

He said he could probably do it tomorrow. I'll definitely take a few photos before installing it.

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wsteve464

Should that read OD? I am figuring the Huffy steerer is to extend your fork steerer and the pipe is the internal sleeve?

rosefarts

Correct.

So the same OD of the inner sleeve is the same size as the ID of the steerer.

The huffy is for the extension. He thought he could build it up and machine it round but with shop time costing what it does, the donor bike saves money.

wsteve464

Yes the sleeve OD should be a close fit inside the steerer tube, a couple of thousands less at most than the steerer tube ID

rosefarts

Picked it up today. I learned an interesting new fact. My fork was originally threaded and at some point in the past, the threads were filled with braze. This wasn't apparent with a thin layer of primer on the steerer. See the gold part of the picture.




That didn't change the repair. He Tig welded it then filled the imperfections with silicone bronze.




When I cut to length (plus a little!!!), there was plenty of room for a star fangled but, so I didn't have to glue or kludge anything.



Overall, it added 0.10lbs to the bike. I can live with that. I'm very happy with how it went together. I should have done this 3 years ago when I got it.