brass or steel

hi is brass or steel screws best for cylinders (gun metal) or any advice would be helpful ( 3 12/ gauge jubilee) thanks dave

If you mean for the screws which retain the steam pressure, then steel, and high tensile too. Hexagon socket cap screws would be ideal if the design allows them. Or 'Allen Screws' if you don't want to be particular what you call them.

If other screws then perhaps otherwise, but we need more info, please.

Cheers, Tim

Mild steel studs and nuts for me rather than screws

.

What a strange comment, Tim

... I would contest that "Allen" is very particular [being a brand name specific to the inventors of the hexagon socket caphead screw]

[yes, I know ... it has "become" a generic term ... but it shouldn't be]

MichaelG.

Edited By Michael Gilligan on 27/09/2015 20:20:40

Or cap head Unbreako screws. Studs, and nuts would be my choice, just make sure they are about one and a half threads above the nut when tightened, and even.

Ian S C

hi david,

definitely not brass. the cylinders are subject to considerable for and aft forces in the frames and you dont want anything working loose.

socket cap head or allen screws are totally wrong for miniature loco work.

i have always used 'fitted' steel BA bolts with gunmetal cylinders. there should be a plain unthreaded portion below the bolt head where the bolt goes through the clearance holes in the frame. often the clearance size specified is far too big for something like cylinder bolts, and also far too big for commercially made bolts which are often undersize on the OD.

i make my own bolts for these sorts of jobs.

cheers,

julian