Anyone able to chase a thread onto 1 1/8 threadless steerer?

[BrushedAluminium]

Anyone able to chase a thread onto a 1 1/8 threadless steerer

for example I have threadless Mag 21 forks with alloy steerer and need to fit to a standard 1 1/8 headset.

1 1/8thTap & Die set or similar

Local Bike shops dont even know what it is!

 

[mk one]

You could try Danson67, aren't Mag 21 steerers replaceable?

 

[mdvineng]

You need a 1 1/8 26tpi die.
If the steerer tube can be removed from the fork crown, it can be done on a lathe.
I have a lathe to do this sort of work.

 

[BrushedAluminium]

appreciate the response, steerer s fitted as far as i am aware I will double check

(im sure it can be removed)

 

[mdvineng]

Why not use threadless? £20 gets you a good one. Postage to me and back nearly costs that!

 

[BrushedAluminium]

Threadless is always an option but its a 92-93 build that I am working on. and catalogue spec is 1 1/8 threaded headset and quill stem.

I dont know which company you are using but shipping would be around £4 (steerer and crown 1/2kg)

 

[mdvineng]

That's £8 so far then. I was only trying to illustrate costs.

 

[dyna-ti]

I'd have gigantic concerns about cutting a thread into an aluminum streerer that was never designed to have a thread cut into it.
Take a steel steerer, and an alloy steerer side by side and look down the tubes. The alloy is considerably thicker, because alloy is weaker than steel.
And you propose to cut into that already minimum size :?

Were it supposed to have a thread, they'd have used a different alloy, of different diameter and wall thickness. They didn't because it was designed for the stresses put on it in an A head system.

It will crack, you will die

 

[mdvineng]

Good point. I wouldn't cut a thread if the wall thickness wasn't capable of supporting such action. 26tpi threads are not deep by comparison and the top part of a fork steerer is lightly loaded compared to the crown.

 

[mk one]

My question was aimed at the point of swapping the steerer for a threaded one, though not many people get to choose the way they die