despair re mill

I bought this in pieces then found out firstly that the top arm was nissing so am trying to find steel round bar about meter long by 2.5in nominal dia.I realise it wont be ground but will have to make do.The finished dia needs to be 2.496ins. Secondly and even worse the taper sockets throughout dont adhere to any taper tooling that i can find.in uk The tapers are bigger than INT3 and smaller than INT4.The included angle is same as INT but mass is different.also slightly shorter overall.An astute person via home w-shop provided me with a sample and he says they were either made or provided by Alfred Herbert.Its taken me three yrs to locate an identical as far as i know taper in USA called collis Quick Fit which is common there. not here. This means im stuck. I read somewhere that its poss to turn down INT tool tapers as they are surface hardened only.But,others say they cant be cut. In any case all my equipt is down at moment and im too ill to tackle it. Cant understand why a uk tool maker would devise or fit non usual tapers in a war situation. I feel like giving in and it makes me feel ill to be defeated.I spose the INT 4 could be put in a furnace but dont know enough about the process of annealing hard stee.What amazes me is how litle info there is on maching hard steel.I thought that was the purpose of carbide but seems its mainly used for high speed production hi-temp work.Im baffled.disillusioned.Can anyone help.Im not a scrounger.Yours 01329841173 all days/hours but often dont hear it. Erica/john. The mill is Adcock/Shipley 1AS 1943 not ES. Location hants uk.

I read your notes through a few times John. I don't want to be defeatist but without specialist equipment or a lot of charity from someone in the UK I think you are fighting a losing battle. You have found/been burdened with an unusual type of mill with missing parts. If it was unusual but complete with all parts and a range of tooling, you could probably manage.

If I were you I would sell it on immediately (scrap or to a dealer) and get a more modern mill with R-8 spindle and enjoy it, while knowing that you can easily get all manner of tooling you need, relatively inexpensively.

Life's too short to fight with a mill for years.

Hope things work out for you.

JD

Taper might be INT35? It is perfectly possible to turn hardened steel with carbide inserts, although they do wear fairly quickly. An alternative is to use a CBN insert, but sit down before you look at the price. Try searching for 'hard turning'; that should find plenty of information on turning hardened steel. Or have a look at this link:

**LINK**

Regards,

Andrew

Andrew bear in mind OP would need to turn accurate, long, steep tapers to an excellent finish to adapt the mill shanks he needs from existing shanks with different tapers. On hardened steel with carbide or CBN tools, this would require a large HP, exceptionallly rigid lathe with a long travel on the compound slide. A very accurate taper angle is needed with milling shanks. Usually they are ground. Machining adapters to fit is hopeless I would say on something like a Myford or Boxford or far east lathe as usually found in home workshops. In soft steel, maybe you could get away with it, but not machining hard steel. Even if you did, it would take a lot of time and care, and would be hard on the machine. All these things are completely unnecessary if a more common mill were in place with R-8 tooling. I can't imagine why anyone would want to put themselves through the difficulties.

JD

I assume you are talking about the version under 'model 0' on the Lathes site.

**LINK**

same seller has a couple of other BT35 items eg

**LINK**

The above would allow you to then use a MT3 arbor (as used I think on the Centec).

You can make a perfectly servicable taper for amateur use from mild steel without flange and put a screw/pin in from the side to take the drive. It won't matter wheter it is int 30, int 40, or int 35 as the extra will just stick out. Then finish bore it in situ for a plain shank endmill and you are in business.

If you can't get the 2.5in bar because the world has gone metric get the next smallest metric and a bit of next biggest (or 'hollow bar' to make sleeves for the bits that need to fit. It will be much easier to turn a short bit to the correct diameter.

I'm rather puzzled by the date on this thread - I'm certain I replied to a version of it a month ago.

Hi John,
I remember seeing a suggestion (I think on this forum.) for a source of ground steel bar. It was to try companies that repaired large hydraulic equipment such as JCBs and similar. It suggested that these companies buy in ground stock to replace the ram on hydraulic cylinders. The topic was someone wanting rod for the column of a pillar drill or mill. You may locate the thread from this information.

Les.

I agree that the simplest solution is to get an adaptor from INT35 to INT30 or INT35 to MT3.

I can't see the overarm as an insurmountable problem, aside from cost and weight, any well equipped jobbing engineering firm ought to be able to machine a bar to size for you.

Neil