fork steerer "editing"

[student]

Hello there.
I was wondering whether it'd be possible to cut the steerer of a threaded one inch fork, and weld a non-threaded (a-head) steerer in the place of it? Would the fork hold together? would it be even possible to do this cheaply and smoothly?

I can't really see the reason why would anyone do this as there's the option to use A-head converter or to simply buy a one inch non-threaded fork (esp. for a guy who works at wiggle..) but it seems there are some who would want to make an attempt for it.

Any advice appreciated.

Cheers.

[meic]

I can see a reason, I have a large bike with a long headtube, secondhand forks are cheap and commonly available but not that will fit my bike.

I just had a quote for replacing the threaded steerer tube on a secondhand fork, £90.

[Mick F]

I don't see why you shouldn't do it. The steerer and the new bit could be aligned with V blocks and tacked together, then welded correctly. You could also use an internal sleeve to help alignment and make it stronger.

This would be a cheaper alternative to replacing the whole steerer because the fork paintwork wouldn't be affected.

I have considered this option for the future just in case I need a newer headset as the one I have now has a low stack height. I've taken the precaution of buying a replacement headset for when this one wears out, so the welding situation may not appear for many years ............ but it is a future option I have considered.

[meic]

I dont think that I could do it.
As soon as the clamps were released the stresses made by the welds on cooling would probably pull it out of true.

[mrjemm]

This was discussed in a thread of mine about converting steerers recently. I think it could've been breakwellmz or... can't remember, who's done something along these lines.

I'll try to see if I can find the thread.

Here you go... viewtopic.php?f=5&t=70664

[Mick F]

Just thinking .............

I had a post on here some few years ago about this very subject, though I was asking about rivets. I think it's been mentioned again over the time.

It seemed to me that by a short and strong sleeve could be made to fit the internal diameter of the steerer. You could cut the steerer an inch or two from the fork crown, insert the sleeve and fit the new steerer on top. By drilling and riveting, you could do the job without heat.

My idea will only work if there's enough room between the steerer and the headtube for the rivet heads, but I suppose you could use pan-head rivets.

[LWaB]

An Aussie framebuilder friend (Frezoni) has done this several times.

[531colin]

Just thinking .............

I had a post on here some few years ago about this very subject, though I was asking about rivets. I think it's been mentioned again over the time.

It seemed to me that by a short and strong sleeve could be made to fit the internal diameter of the steerer. You could cut the steerer an inch or two from the fork crown, insert the sleeve and fit the new steerer on top. By drilling and riveting, you could do the job without heat.

My idea will only work if there's enough room between the steerer and the headtube for the rivet heads, but I suppose you could use pan-head rivets.

Greatest stress (bending moment) is at the crown....think about braking, bumpy roads....how do you access the end of the rivet inside the steerer?
Check your life insurance covers suicide by stupidity before trying this.


I have silver soldered an extra bit of steerer on using a bit of quill stem as an internal sleeve. OK to ride for a month to check if you like the bike before paying for new forks/proper steerer replacement, but I didn't consider it a permanent fix......this bit of tube is both stressed and safety-critical.

[nickpaton]

Just thinking .............

I had a post on here some few years ago about this very subject, though I was asking about rivets. I think it's been mentioned again over the time.

It seemed to me that by a short and strong sleeve could be made to fit the internal diameter of the steerer. You could cut the steerer an inch or two from the fork crown, insert the sleeve and fit the new steerer on top. By drilling and riveting, you could do the job without heat.

My idea will only work if there's enough room between the steerer and the headtube for the rivet heads, but I suppose you could use pan-head rivets.

To further strengthen the joints, I'd use that Aradite epoxy (blue and white tubes) adhesive that takes 24 hours to fully set, when it will be rock hard and would have to be ground off to remove it and should make a good metal to metal joint in addition to the rivets.

[Mick F]

Yep, good idea about the epoxy adhesive.
The whole idea is to replace a steerer without affecting the forks and the paint finish. Rivets and epoxy works for me!

Sorry Colin, you may have misunderstood, or I may have not explained properly.

Make a sleeve the correct diameter to fit the inside diameter of the fork steerer.
Cut the steerer near the bottom or as far away from the bottom as you can get away with.
Slide in the sleeve and rivet it to the cut off steerer. A mandril held firmly in a vice can be used inside the sleeve to bash the rivet against.
Slide on a new steerer with the sleeve cut to an appropriate length.
Rivet the new steerer to the sleeve.

This operation needs to be done delicately, as all riveting needs to be done of course. One at a time and adjusting and not drilling at all until each rivet position worked out. This is all done one at a time as each rivet "swells" the metal and moves any pre-drilled holes.

[531colin]

I understood perfectly, Mick.
As an ex-Navy man, you have probably heard the joke where a sailor is showing his shipmates a card trick, when the ship is torpedoed and lost with all hands.....the only living thing to survive is the parrot belonging to a crew member, known for its extensive and profane vocabulary......but now all it will say is "bloody silly trick" over and over again.

[Mick F]

It was just an idea of mine.
No recommendation. No experience.

Why wouldn't it work?
Have you tried it?

No axe to grind, just curious.

[531colin]

Wouldn't touch it with a barge pole, Mick....steerer is round, small, internally-butted at the bottom end....
I showed a pal my steerer I had extended by silver soldering at the top (as strong as brazing, pretty much)....he had a pink fit, said he wouldn't ride it round the block (but he has a carbon bike now....)

[jb]

The only way to do this is to un-braze the tube and re-braze a complete new tube in.

If its one of them silly welded types place it on a brick and hit it several times with a large sledge hammer. this won't fix the tube but it might save your life. This component takes no prisoners, go purchase a new one.

[Mick F]

Mine is parallel all down its length ......... I think.
531c throughout etc.
I'll check next time my forks are out, but I reckon it's true. Can't say I've noticed any butting in there, but I could be wrong.

I still ask the same question:
Why not rivet an extension using an inner sleeve? I can't say it would be weaker than a thin continuous tube.