High Tensile: What Steel Grade?

I need to make a very long piece of studding (aprox 1 metre long), 8mm diameter and threaded M8 at both ends. It wants to be stiff but not brittle. Does anyone know what grade of steel I'm looking for (EN16? EN24) if I want something that equates to a high tensile bolt but which I can still cut a thread on? I could use silver steel but that doesn't feel right and is rather prone to rust a bit too easily.

Hi Chris,

the steels you suggests should be Ok. In the socalled T condition they machine well. There are also high tensile stainless steels, but they would cost more.

Thor

Yes, go with the high tensile EN16. I found silver steel a bit brittle and prone to fracture under heavy shock loading (front axle for my motorbike when I was a teenager.)

You can buy high tensile studding in most threads from Cromwell.

Clive

Stiffness (modulus) of all steels is close to identical - did you really mean 'stiff' or did you mean strong?

Chris

I would go with EN 24T it is readily available not difficult to machime or run a die down. I use it ctankshafts in high performance model engines when I cant find a 8.8 bolt to make them from. not very technical but it works. It a much nicer steel to work with than silver steel.

Olly

Chris,

I second Olly's recommendation to use EN24T; I have used it for quite a few parts, and it does machine well for a high tensile alloy steel. Noggin End Metals and Mallard Metals both suply it, among others.

David

Edited By Chris Trice on 03/05/2013 14:40:06

The smallest diameter Noggins went down to was 10mm but M-Machine Metals had it in 5/16th which is so close to 8mm as makes no odds.