I've got a good old road frame that I'd like to widen the rear hub spacing to fit a 9 speed hub into. Is it possible to do this as a DIY bodge or is there a more controlled way of doing it, ie a specific framebuilders tool. I was thinking of trying it with some threaded rod and some washers.

If it's steel I think that it will just spread the 5mm you need without much trouble.

I'm sure someone will confirm that or otherwise before you try it though !

Have a read of this http://sheldonbrown.com/frame-spacing.html 🙂

Looks like I was right. Ta.

"Ideally, the frame spacing should exactly match the hub spacing. This makes for easiest wheel replacement. In practice, however, there's a fair amount of latitude in fit. In fact, when the first 130 mm 8-speed hubs were introduced, they had locknuts with beveled sides, so that you could "spring" apart the rear triangle of a frame made for the then-standard 126 mm spacing.
In general, you can safely go up one size in spacing this way, just springing the frame apart. I can't give you an absolute guarantee that this won't cause damage, but the odds are very much in your favor.

If, however, you want to do it right, and your frame is steel, cold setting is the better way to go.

If you're going more than one size, say from 120 to 130, or from 126 to 135, you should definitely cold set the frame"

I just had a read of the plank bending method. Wow that takes nerve!

What I thought of doing was using threaded rod through the dropout slot like an extra wide threaded axle. Inserting a washer against the dropout on each side with nut inboard and outboard. The unscrewing and screwing a couple of faces each side till I reached 130mm. LBS has dropout alignment tools.

Its a 531 steel frame.

i've got and had a few old steel road frames, that have had various width hubs in them.
all i've ever done is pull the drop outs apart to get the wheel in if it's been a wider one.
they seem to have been resilient enough to deal with it, and the wheels seem to sit straight too.
current frame is a 531 raleigh which is fine too.

Yep, just pull em apart as you slot the wheel in… time honored technique of us ancient ex roadies. This is what steel does best and why it's still the go for long distance touring – you can bend and weld it pretty easy.

Cold setting just means bend accurately. Not to be done with carbon 🙂

Sheldon Brown was saying that just spreading the dropouts without realigning them can cause stresses to the axle. The more I think about it, I might heep the spacing at 126, because I may also try and fit a fixed hub to it. Are they mostly still 120mm spacing?

I've done it myself. I just bent each side until it was right. No problems. 2mm each side is a non issue.