Fixing a Victorian

[Mickeyspinn]

Yup that's the way in for the collet ! Might find theres just enough thread for the nut to pop it over its register/stop...which really doesn't need to be big...once it's sprung it's in! and I'm certainly with you on that bottom bracket shell being like the rest of the lugs...internal and i reckon laminated ....
We'll eagerly await nabeaquam's return to archival duties

 

[Woz]

In all honesty, I had a long day yesterday, it just so happened I drove some 100 km in superb wine country and all I could think about when getting back home was have some. I peaked early on an empty stomach and overshot to the point I couldn't find the power on button on the laptop: the whole laptop was just a blur. Over and Well Out.

I'm rather proud of that drawing tonight, but yeah, looking at it again the paper grid lines look more of a suggestion than a reference

 

[Mickeyspinn]

A little bouteille bootay !

 

[Imlach]

In all honesty, I had a long day yesterday, it just so happened I drove some 100 km in superb wine country and all I could think about when getting back home was have some. I peaked early on an empty stomach and overshot to the point I couldn't find the power on button on the laptop: the whole laptop was just a blur. Over and Well Out.

I'm rather proud of that drawing tonight, but yeah, looking at it again the paper grid lines look more of a suggestion than a reference

I find that aggressively attacking the general keyboard area with greasy hands after scavenging in the fridge for a sausage or a lump of cheese usually works. Eventually you strike the magic button, as I groan while trying to guess the location of the picture that Microsoft picked today as my lock screen.

 

[Woz]

I like what grantoury said further up. I think he's on the nose. Nothing on this bike suggests cheap and corner cutting.

 

[Mickeyspinn]

I like what grantoury said further up. I think he's on the nose. Nothing on this bike suggests cheap and corner cutting.

Yeah ! For some strange reason...it makes me think of tucker cars....I don't know why other than just doing it differently and doing it to the max!

 

[Woz]

Yup that's the way in for the collet ! Might find theres just enough thread for the nut to pop it over its register/stop...which really doesn't need to be big...once it's sprung it's in! and I'm certainly with you on that bottom bracket shell being like the rest of the lugs...internal and i reckon laminated ....
We'll eagerly await nabeaquam's return to archival duties

I was thinking of that. Also was thinking a longer threaded nut could have been used initially for assembly to compress the collet sufficiently to go over the stop / register, provided there is enough thread in the lug. I was also thinking that the lock nut would / should have an overhang lip just going over the outer lug diameter just to hide a few microns of insertion depth wiggle, but it doesn't.

More I thought about more I believed it is a precision piece of engineering with limited wiggle room and everything built to an established tolerance.

 

[Mickeyspinn]

I was thinking of that. Also was thinking a longer threaded nut could have been used initially for assembly to compress the collet sufficiently to go over the stop / register, provided there is enough thread in the lug. I was also thinking that the lock nut would / should have an overhang lip just going over the outer lug diameter just to hide a few microns of insertion depth wiggle, but it doesn't.

More I thought about more I believed it is a precision piece of engineering with limited wiggle room and everything built to an established tolerance.

Yes a collet isn't a collet unless it's bang on to size....thats where similarities will differ to a compression fitting which can be a bit baggy out of round etc it's all squishy stuff whereas steel not so!
I had another stare at the image of the nut when fitted on seat tube there's a quite a chamfer on the top of the collet .....it's possible that's the grab point...but would need to see the nut! That could change our thinking again

If that were the case there'd be ring marks around seatpost...

 

[Woz]

Yes a collet isn't a collet unless it's bang on to size....thats where similarities will differ to a compression fitting which can be a bit baggy out of round etc it's all squishy stuff whereas steel not so!
I had another stare at the image of the nut when fitted on seat tube there's a quite a chamfer on the top of the collet .....it's possible that's the grab point...but would need to see the nut! That could change our thinking again

If that were the case there'd be ring marks around seatpost...

Yup. Noticed that chamfer / taper too. But there is no slit at the top, so it can't compress on the seat-post there (if I understand the collet principal sufficiently).

I reckon when Nabeaquam checks in and see's all this he will head straight to the fridge, grab a beer and put us all right!

 

[torqueless]

A collet so slim that it has to fit within the couple of mm available between the internal diameter of a seat tube and the external diameter of a seat post? I reckon you could install that from the top opening of the seat tube, you wouldn't have to do it from the bb. It may not even be 'captive'. If the slots were wide enough to squeeze together to get it in, then it could be got out the same way.


Maybe the outer 'female' conical part of the collet is integral to the seat lug?