What steel to use

I have been looking at some plans for various bits of kit and noticed that Harold Hall notates his drawings with a numbers like Steel 230M07 and Steel 080A15.

What do these numbers denote and are there lists of the different kinds ?

Hi Chris,

They are BS numbers, which replaced the old wartime EN numbers back in the 70s. The first one, 230M07, is a free-cutting carbon steel (the 2) having 0.3% sulphur (30) and 0.07% carbon (07). The M denotes that is complies with required mechanical properties. It is the same as the old EN1A, the steel so beloved by model engineers.

The 080A15 is a 'straight' carbon steel (0) having 0.8% manganese (80) and 0.15% carbon (15). The A denotes that it complies with required chemical properties.

Every country seems to have its own set of standards but there are cross-reference lists on the web, often on steel manufacturers' sites. I have such a list but can't remember where it came from. If you are interested I'm sure that Googling 'steel grades' or something similar will bring up something.

Regards, Brian

That's great Brian, thanks.

I generally get my metal from M Machine in Darlo cos they are local. When you look at their listings they will provide the BS numbers. I have to assume that other suppliers do similar..

Yes my local supplier will use numbers but they don't mean much to me at this point in my engineering life.

For example the two numbers in the OP that Brian explained in great detail for me (thanks) however it went over my head a bit. That said I realise I can't expect eveyone to spoon feed me info but it gives me something to work with.

Chris,

You might find this book quite a useful introduction to most of the materials of use to model engineers, including the commonly used steel grades: **LINK**

David

Brilliant thanks

Having Chris J referred to the specification numbers I quote for my projects I feel I should comment. There are hundreds of steel specifications but only a handful will ever find a place in the home workshop and of the handful two are likely to cover 99% of all steels required in the majority of workshops.

230M07 (very close to EN1A in the earlier spec) is only available in rounds, hexagons and a limited number of square sizes, and is predominantly a free cutting steel intended for use on the lathe. A version of this with a small amount of lead added machines even better and is known as 230M07Pb. Unfortunately, very few of those supplying the home workshop stock this.

080A15( previously known as “good commercial quality&rdquo is available in the above shapes but also in a very wide range of flat sizes. Because of this it is a material for use on the milling machine. However it machines less well than 230M07 so is not ideal for turning, though of course can be.

070M20 (very close to EN3B in the earlier spec) is a number I now quote in preference to 080A15. This, whilst almost identical for most applications, is because it is more widely available from those supplying the home workshop.

This I feel is all you need to know for the vast majority of work you undertake, that is unless your workshop activities becomes very specialised.

A little more thought will be needed if you get into welding or case hardening which is possible with all the above (except when leaded) but there are preferences and would advise that the subject is researched when such a need arises. Similarly, if you start making parts that will be highly stressed, or need to be hardened, then cross that bridge when you come to it.

I terms of machinability, Macreadys in their catalogue use 230M07 as a base for which they quote a value of 100, for 230M07Pb the value is 130 and for 080A15 and 070M20 a value of 55.

Just to avoid confusion, Macreadys is a large supplier to industry and does not supply small quantities.

I would advise that you do purchase materials to known specifications and mark any left overs with some form of identification. Do Not purchase from suppliers who just state bright mild steel as you have no idea what is being supplied. Worse still, you will end up with some materials that machine well and some that machine poorly with out any knowledge of why.

We have seen questions to this forum where individuals ask why they are not getting a good result but do not know the steel they are using. Comparing 100 with 55 above shows that there can be quite a difference even with commonly available steels.

Hope this help ChrisJ

Harold

Thanks everyone for all for the help.

Good answer Harold, nice for a learner driver like me !

Chris

How come the smiley, together with extra characters, appeared in my comments above?, I did not put it there.

Harold

It's just a little comuter glitch is my guess.

I think you're gilding the lily a bit. Most of the model engineer suppliers that I'm aware of don't quote the BS numbers for any of the metals they supply, indeed I remember phoning one to ask if they sold EN1A steel and the reply was "All our steels are free-cutting". And stainless steel is even worse.

If anyone can tell me the name, address and phone number of a supplier who even knows about metal grades and is prepared to sell small quantities, I would be delighted to shop with them.

Bernard

A useful table showing these steels can be found here.

Unfortunately this numbering system (to BS.970) has been superceded by that in BS. EN. 10027 which I find very confusing and gives very little information as to what each grade is suitable for. It even gives two distinct systems of classification, a symbolic and a numeric one.

Here in France most suppliers stick to the old French system.

Russell.

Bernard

This guy seems very knowledgable and likes to chat.

He is in Great Yarmouth but will have whatever you want delivered straight to your door.

Chris

**LINK**

Harold,

I drew David C's attention to this problem last month; see: **LINK**

David

Bernard,

I think you have been a little unfortunate in the metal supplier you approached. I have found the chaps at Mallard Metal Packs, **LINK** and Noggin End Metals, **LINK** are both helpful and knowledgeable, and are often able to source specific grades of metal not in their normal catalogue.

David

The following Bernard are two suppliers who advertise in ME/MEW and who stock a vast range of metals, not only steel but many others, some special.

In almost all cases they quote either the earlier of present day specification numbers.

MK Metals even supply additionally to EN1a/230M07 the leaded versions.

MK Metals at **LINK**

M-Machine at **LINK**

If a supplier states only bright mild steel then this is probably what they ordered. If they had ordered, say ENI A, surely they could quote in the catalogue Free cutting mild steel EN1A.

If then they only ordered bright mild steel they are at the mercy of accepting what ever the supplier chooses to supply, which may differ from batch to batch

I am presently trying to use up steel that I purchased before I took this decision to be more demanding as to what I am being sold. As a result, I often find myself using material that does not machine as well as I would like and am very tempted to dispose of it as scrap, but the bank manager part of me often prevents that..

Harold

metals Supermarket give the EN numbers of all their steel, including short ends, and have a wide selection. I have EN1A in 1 1/2" and 2 1/4" bar at the moment, and straight square EN1A which machines almost as well.

Neil

Just a thought ...

Model engineers are not alone in "having trouble" with "new" EN specs Eg EN 230M07

At work we are increasingly seeing drawings with EN numbers ( not to be confused with EN1A)

so faro good..now customer wants this spec and this spec only needs mill cert. for metal

BUT has to say (for exmple) EN 230M07 . A mill cert. declaring EN1A will not do.

No the mill can't put both on cert. or supply cert saying (for exmple) EN 230M07..

nor can any other mill...."funny" says customer.."had all our suppliers saying them same thing..."

Used En1a as example but real nightmare in bronzes even when the specifed bronze has wider spec. than an available alloy...

So you are not alone ,at least many tables of equivalents are available online to model engineers and sec.s are "converted" easily...shame customers can't read for themselves

While not quite on topic but still a "materials" point, I emailed CES today and had my mail intercepted by "Spamarrest". They asked me to verify my email address before me email would be forwarded to CES. Anyone else had this happen? I will delete the email and phone them instead.