Ametuer 'cold set' advice

[NHS Biker]

I went and visited Ace UItra Cycles in Wolverhampton. I was discussing whether to apply the cold setting method, and he said, don't bother, give me the frame, I'll put it in my jig and sort it out for you. Turns out he has over 35 years frame building experience, and has built frames for most of the UK's cycle cross riders, he bought all the tubes and machinary from TI Reynolds when they closed the Birmingham factory. Result. All I want now is to find some 1984/85 Raleigh Record Sprint Aero Contour decals.

 

[Red Light]

Spring back wouldn't occur if you did it as a slow process. 1 turn on one, then another turn on another and then keep the bar in place for some time.

All the frames I have cold set using a set up like the one you described have sprung back. Speed doesn't come into it. You need to overdo it and then let it spring back, measure, go a bit further still etc until it springs back to the width you want.

 

[smokeysmoo]

All the frames I have cold set using a set up like the one you described have sprung back. Speed doesn't come into it. You need to overdo it and then let it spring back, measure, go a bit further still etc until it springs back to the width you want.

+1 for the two I've done. Both using the threaded bar method.

 

[PpPete]

and a few more with the threaded rod here.
From memory a 120 mm spacing on Reynolds 531 needs to be spread to about 150mm so that it springs back to 130mm-ish, but take it gently, a few mm at a time, as having to squeeze them together again is probably to be avoided (although I've had to do it after overcooking Sheldon's method with timber)

Never had a fatigue problem.... equally doing it slow or fast makes no odds to the springback on steel IME.... although it might on titanium if you were foolish enough to try that.

 

[mickle]

Ive never heard of the 'a little bit a day' theory and i don't believe it for a minute. The nuts and bolts and straight edge method may deliver a bit more accuracy than the string method. Depends how accurate you want it to be. I can get to within a mm with the latter.

Whats much more important is drop-out alignment, particularly if you value your rear hub. Just about the worst thing you can do to an IHG is bolt it into skewiff (spl?) drop-outs.

 

[Ed no-more-lemons]

No rush on this. almost forgotten post.
The more I research this the more confident I am in having a go.
But as I currently have a set of 700 wheels that sit well and parallel in this frame, I want to do some milage as it is before mid winter sets in.
The plan is to restore the original 27 inch wheels after the cold set and getting shot of the bike.
I was surprised in prising my avatars front forks to make a wheel truing stand how little spring back ocurred. This was a bit tricky without a plank for leverage and presumably pulling and not levering, meant the force was being applied at more of a right angle.
I was just wondering whether anyone has fettled an alignment gauge or whether this is a tad OTT, when a straight edge and bit of string would ensure symmetry and alignment.
Symmetry with the forks was easy with a few pencil line in 2D especially as I am unlikely to ever attach them to another frame, although accuracy to within 1mm was fairly straight forward.
Having got hold of a split bar arrangement. I am thinking of using some old tent poles with blades attached to attach a centre line to the frame running from the seat post clamp/slit to the brake bridge and extending on to the split in the bar/bars.
No doubt the professionals out there use the proper alignment gauge tool, but surely something almost as effective can be cobbled together without to much trouble and at very little expense.

 

[warthog]

Cold setting works fine - you are using a natural property of the steel - but if you just force the back lugs apart too much then one or both of the chainstays will squish in - try it on a spare bit of 15mm copper water pipe and see the effect. You also have to be careful not to strain the brazing where the chainstays meet the bottom bracket. AND you can end up with the lugs splayed making wheel mounting tricky. What you are trying to do is bend the chainstays rather than stress the point where they meet the bottom bracket. I wrap soft rope tightly around the chainstays half way along before the nut and threaded bar approach to encourage a progressive bend. But it can still go horribly wrong. Unless you're planning wild descents of the Ventoux then anything other than visual alignment is really not too critical.

 

[rayms]

How much does the frame weaken from cold setting??

 

[Dogtrousers]

I use an 8 speed hub in an 80s vintage (originally 5 speed) frame. I can never remember the mm sizes.

Anyway, I wrestle the wheel in. Its not that difficult unless you are fixing a puncture by the roadside with others watching on impatiently. Then it's near impossible.

Note that the smallest sprocket on the block is out of bounds as there isn't sufficient clearance.

Some threaded bar recipes are very exact that you must turn each nut an equal number of times or one side will spread more than the other. That's cobblers. Think about it

 

[raleighnut]

I use an 8 speed hub in an 80s vintage (originally 5 speed) frame. I can never remember the mm sizes.

Anyway, I wrestle the wheel in. Its not that difficult unless you are fixing a puncture by the roadside with others watching on impatiently. Then it's near impossible.

Note that the smallest sprocket on the block is out of bounds as there isn't sufficient clearance.

Some threaded bar recipes are very exact that you must turn each nut an equal number of times or one side will spread more than the other. That's cobblers. Think about it

That is probably going from 126mm to 130 so pretty easy to 'spring' the wheel in, My Raleigh Road Ace (531c) frame has that set-up but it wouldn't work with a 135mm hub.
No-one has mentioned the real danger with cold setting though, it can crack the brake bridge brazing.

 

[gbb]

That is probably going from 126mm to 130 so pretty easy to 'spring' the wheel in, My Raleigh Road Ace (531c) frame has that set-up but it wouldn't work with a 135mm hub.
No-one has mentioned the real danger with cold setting though, it can crack the brake bridge brazing.[/QUOTE]
That was my major concern when I did my Clubman. The brake bridge is basically a tube brazed onto relatively small diameter rear stays and I was worried about the brazing cracking so I (IIRC) clamped the rear stays JUST below the bridge to (hopefully) prevent problems. Anyway, several years later, it's all still OK.

 

[r04DiE]

Seems that this 'string theory' has put my mind to rest...

WTF?