3.125" brass tube

I am building 3.5" gauge Titfield Thunderbolt and am looking for brass tube 3 and one eighth inches (3.125" ) diameter x 16 swg for the smokebox. Does anyone have any suggestions where I could get a suitable piece? Offcut or similar.

TIA Malcolm

Edited By JasonB on 11/03/2015 19:33:14

I thinks its quite hard to get the 1/8" increments these days so you may have to resort to rolling from flat sheet or get the nearest size up and cut a little out, close it up and solder back into a ring placing the joint at the bottom out of site. M-Machine have 3.25 x 16swg brass by the inch.

Reeves used to do odd size bits for smokeboxes but I think they stopped doing them a while ago

J

Hi Malcolm,
Have you considered 80mm (3.149" )  as this is only 24 thou above the size you want and I would imagine that would be a standard size.

Les.

Edited By Les Jones 1 on 11/03/2015 19:46:16

I think brass tube is one of those that still comes in imperial measure at least in the larger diameters.

Did find  3.125" here but not sure if they will do short lengths

Edited By JasonB on 11/03/2015 20:13:37

I think you must be correct Jason as I cannot find any with Google or on ebay.

Les.

Malcolm....GLR Kennions Ltd list 3 1/8" seamless drawn copper tube at £35 per 300mm. Their telephone number is 01279 792859.

Mick

hi malcolm,

i think you would be better off cutting up a bit of 1/16" brass or steel sheet and rolling into an upside down 'U' shape for the smokebox wrapper.

cheers,

julian

Julian

The brass tube is for the smokebox proper. It has a wrapper made from 22 swg steel shaped as you describe. I assume that the external view of the smokebox is an upside down 'U' to fit the smokebox front, with a normal cylindrical smokebox under the wrapper. It is not very obvious from the drawings that that is what is meant.,

Thanks Mick H but Kennions tube is copper in that size but I appreciate the link as I had forgotten about Kennions!

Malcolm

hi malcolm,

there isnt really any need for an internal bit of tube, and the smokebox can be made as per fullsize but with a flat plate on the bottom of the 'U' fixed with brass angle. pipe connections will also be much easier and smokebox volume for ash increased.

cheers,

julian

Thanks Julian. That sounds like a good idea

Cheers

Malcolm

Thanks Mick H but Kennions tube is copper in that size but I appreciate the link as I had forgotten about Kennions!

Sorry Malcolm, I should have read your question more carefully. Although I work in a smaller gauge, I tend to do what Julian has suggested.... made easier since I bought a rolls.

Mick

Would 1.6mm/16 swg be thick enough for a smokebox?

I should have said - Would 1.6mm/16swg BRASS be thick enough for a smokebox?

hi malcolm,

1.6mm brass will quite ok - i make all mine out of 1/16" steel sheet as it takes paint better (and cheaper!)

in my albums there are some pics of my 5"g terrier Stepney smokebox being rolled out of 1/16" steel plate with my very basic home made rollers.

cheers,

julian

here's some of the pics before silver soldering the joint. note how crude the rollers are!

cheers,

julian

the completed smokebox for my 5"g terrier Stepney,

cheers,

julian