It does sound as though the brass was being squeezed between two rollers, rather than just bent around three. This is a 'standard' technique for reducing sheet thickness, but it puts a big load on the rollers etc, and if they are not man enough they will be forced apart – and more apart in the middle than at the edges. Hence your frilliness.

'Pretty much maximum' with any modest tool is likely to show its limitations.

Cheers, Tim

Brass does work harden but also air hardens over time so it will ease the rolling process if you anneal it first.

The rolls should only be tightened enough to grip the sheet sufficiently to feed it through the rolls. Don't try to roll it to tightly on one pass, do it in several rolls and increase the amount gradually. You may have to anneal it more than once to get a clean roll.

Are your feed rolls geared together? If so you shouldn't need excessive pressure to allow successful feeding.

My first thought is -28 sgw is pretty thin so shouldn't put a big load on any set of rollers.

Second thought is, you can always roll it in more than one pass, which might make it less likely to distort.

Neil

I have a set of geared rollers made to the GHT design, and have experienced the same effect as Mick has described. The solution here is to remove one of the gears, hence disabling the gear train and reducing the pressure.

Roger

Graeme W – interesting thought, but I can only comment on my own experience.

In his workshop manual book (p 213), GHT says "An interesting feature of the proposed gear drive is that any increase in the resistance to movement of the work through the rolls is accompanied by an automatic increase in the pressure between the driving rolls" I can only think that in my case I started off with too much pressure and that the resulting resistance further increased the pressure between the rolls and resulted in deformed edges.

You have probably avoided the problem by reducing the pressure from the top roll, whereas I've not increased the pressure by removing a gear – same result.

Mike, I did something similar by cutting strips from a suitable size tube 1 piece of tube would provide all you need. when the piece is cut and cleaned up, I can be soldered to the tender side.

Chris Gunn

Mike,

You could insert a piece of suitable wood inside the tube, then cut with either a tubing cutter or fine tooth hacksaw.

The wooden insert prevents the tube deforming……