BA, ME, Metric Coarse or Imperial : which taps and dies to buy ?

I actually used a junior hacksaw. The slit is a little wide for the smallest size (3/32" dia). You could start with two bits of brass clamped together but then you would have to do a fair bit of filing to open up the gap.

Russell.

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Or maybe just clamp a strip of brass shim between them; drill on the centre line and discard the shim afterwards.

MichaelG.

Beat me to it Michael - but being "careful" I have a stock of tin sheet (cut with snips from old biscuit tins) for jobs like this and other uses - to protect work held in the chuck jaws for instance. Always useful stuff to have around.

Also completely agree with Michael G's earlier diagnosis by the way Brain. Either your die is defective or it's a problem of technique, which would boil down to patience and practice. Anyway - good luck, it's all part of the fun!

Regards,

IanT

It varies, but generally as follows:

Metric taps (hand, spiral flute and spiral point) and dies, some BA and BSP from CIS Direct as they're my localish tool shop (St. Neots) and I can check prices before buying - mostly OSG brand

ME hand taps and dies - The Tap and Die Company www.tapdie.com

Everything else, BSW, BSF, UNC, UNF and NPT from Drill Services www.drill-service.co.uk

For larger taps and dies, from about 3/4" up to 1-1/2" I've bought off Ebay over the years - always recognised UK/US brands - although most of the larger threads tend to get screw cut on the lathe.

Regards,

Andrew

1. Has anybody used this mini metric set of HSS taps and dies ?

**LINK**

They look quite useful and I am thinking of purchasing a set.

2. Will any metric 2mm screw or bolt fit the 2mm tapped hole I cut with this set ? Are there different thread pitches in the metric system ? I am still a bit confused !

3. Who sells small metric nuts, bolts and screws to match these sizes  ?

Edited By Brian John on 05/11/2014 12:53:40

Brian

They might work OK - can't say as I've never tried them, but you'd be better off buying taps and dies as you need them rather than in sets that probably contain sizes that you 'll never use. Those dies are solid so you can't adjust them for size so bearing in mind the problems that you had (still got?) with threading your brass tube you could well be getting the same issues with this set as well..

There are LOTS of different thread pitches in the metric system 3 different pitches for 2mm nominal size for example. As to what pitches there are, then a search using Google will bring up a number of sources that will tell you and should indicate what are the normal (coarse) and fine metric pitches. The common commercially available metric fitting are pretty much all to the coarse standard.

If your taps and dies are good quality then they will cut accurately and any commercial nuts and bolts should fit the threads that you've cut - that was the whole reason behind Whitworth's work on standardising screw threads way back when.

As you're in Australia it's a bit difficult for anyone in the UK to advise you on where to go for supplies - there must be someone closer to you than the UK, why pay the high postage rates - unless it woks out cheaper than buying from a supplier in the southern hemisphere

Edited By Keith Long on 05/11/2014 13:09:52

1. It is always cheaper to buy from the UK then to buy in Australia, even when postage in included. There are too many middle men here in Australia !

2. This beam engine requires taps M2, M3 and M4 but it does not specify the pitch or thread. How do I know what to buy ?

**LINK**

If it doesn't specify pitch then the assumption is that it will be coarse pitch in metric. If you need to use fine pitch metric then it WILL say as they are not commonly used unless there is a good reason for doing so.

High on your purchasing list should be a set of "Zeus" tables or Tubal Cain's Model Engineers Handbook, they will give you just about all the information on screw threads that your likely to need.

Edited By Keith Long on 05/11/2014 13:55:08

Personally I wouldn't accept the aforementioned tap & die set as a free gift. I made the mistake many years ago of buying a similar, larger, metric set - completely useless. If you only need M2,M3 and M4 buy just those.

All metric threads have the same (60° included angle) thread form. It doesn't really matter what the pitch is, as long as you're consistent. However, metric coarse is by far and away the most common, so I'd use metric coarse for all three.

Regards,

Andrew

Edited By Andrew Johnston on 05/11/2014 13:57:29

If the drawing merely says "M2", "M3" or "M4", then take is as read that it s a Metric Coarse thread.

Don't worry about the Fine and Extra Fine threads unless specifically called for. They may be nice to have, but won't see much use, if any!

I have sets Taps and Dies for different threads; some of which have never been used.

(Years ago, at work, I dealt with UNEF threads, but have never found the need for them at home, so have no facility to produce them, other than setting up then lathe if ever needed).

M.E.40 threads are useful, as a fine adjustment, (0.025 inch / rev for Luddites like me).

Russel's suggestion of gripping the work in a split collet is a very good one, and will prevent the tube being crushed (At 3/16 OD it likely to be fairly weak, especially if thin walled)

To really insult you, you are offering the end of the die with the larger internal chamfer onto the work, aren't you?

It SHOULD be the end marked with the thread details. I have been supplied with the odd die where the marking was, incorrectly, on the other end, but Tracy changed it without any demur.

Have you a female thread, into which this 3/16 brass tube has to be screwed?

If so, my suggestion is to use this as a gauge. Back off the outer two screws in the die holder, and tighten the centre one, to open the die, and then cut a thread. Try the result in the female. If it won't even start, then slacken the centre screw a little, ( maybe barely a quarter turn) and run the die down the thread again, before retrying. Keep on doing this until you get a thread fit which feels right, (smooth without being loose), but remember that a small adjustment can make quite a difference. If it squeals, it's too tight!

As a final check, then cut a thread on "virgin" tube, and check that the fit is as you want. If it is, you are ready to go into production.

On the subject of lubrication, it is normal not to lubricate copper or brass, because of their property of acting as a low friction bearing material. Cast Iron contains graphite, so that acts as a lubricant, and so no extra is needed. For Aluminium, something like kerosene (paraffin) is the usual recommendation. For steel, I use either Rocol STD, or quite often, the fat melted off the breakfast bacon! After all, Tallow was used by engineers before the advent of more advanced lubricants.

Hope that this is some help, but all these posts show how Model Engineers are always prepared use their experience to help each other, in whatever way possible.

Howard

(A) M2, M3 and M4 : If you look here on the Tracey Tools website there are numerous metric coarse taps on offer eg. 4 X .5, 4 x .7, 4 X .75 ! Same with M2, M3. Also, would you buy the intermediate tap or just make do with the taper tap and plug tap ?

**LINK**

(B) Howard : Yes, I am using the correct side of the die.

(C) Note on cost : Tracy also offer a 2 to 6mm metric coarse set in a box (HSS taps and dies) ; this is cheaper than buying just a few taps individually. It is not always good sense to buy a few as you need them. I assume that they are the same quality as the taps that they sell individually.

http://www.tracytools.com/taps-and-dies/taps-dies-wooden-box/metric-coarse3

Edited By Brian John on 06/11/2014 03:06:11

Edited By JasonB on 06/11/2014 07:36:03 (hit edit not quote)

Edited By JasonB on 06/11/2014 07:36:37

I use a lot of threads under M6. So a lot of taps and dies have been purchased. As most of my threads are in al.alloy I have pretty much given up on the taper or first tap, simply buying intermediate and plug taps. I have found that this works fairly well in the harder materials, like steel. However, over M6, I still get all three taps in the courser pitches. For instance I recently required M10 x 1.0 RH and LH taps and dies. Partly....no mainly, to reduce costs I got just the inter and plug taps.

At one stage it seemed to me that I wasn't involved in "model engineering", but "tap and die buying". Maybe that's just my warped outlook!

The serial taps from Arc Euro, and Ausee (up here in 'straya) are good value and they come as a set of three. They do seem to produce good threads, but the range of sizes is limited.

Best of luck

cheers

Bill

I thought that until I decided to make some bedding pillars for an Anschutz 1411 Match54 .22 rifle.(1974 vintage).

Aaarg! M5-Fine socket-head action screws. Having a heck of a time finding long replacements here in Oz. Oh well, that's what the lathe is for (unless anybody knows where to purchase them locally).

* Danny M *

Bill : Most sets supply taper and plug tap ie. #1 and #3 but you have chosen the intermediate and plug tap ( #2 and #3 ). Isn't that a bit unusual ?

Edited By Brian John on 06/11/2014 06:08:30

To hold the tube:- drill a hole through a piece of 2" X1", through 1" face, it should crush in the vice, or if it does not slit the wood with a saw. Else wrap some masking tape around the tube. Or do both.

Frank

> Bill : Most sets supply taper and plug tap ie. #1 and #3 but you have chosen the intermediate and plug tap ( #2 and #3 ). Isn't that a bit unusual ?

I've asked for that combo as a special before now, taper tap does very little if you use a 60&% engagement sized hole.

Neil

My first set of taps was BA in a wooden box although mixed in manufacture. This was sixty years ago from a shop in Farringdon Road (London) which didn't seem to sell other tools. Looking back I suspect they had had a good war and were of varying sharpness. Since then I have bought as required (Not many of these), some I thought would be useful such as some ME. When I lived closer a visit to Tracy tools was always expensive but Very Good Value.

I have also bought random taps and dies from end of lines in shops and stalls - usually HSS was on offer.

Result is a three decker collection of all sorts from 14BA to 1/2 whitworth.

John

That's odd, my taper taps cut a perfectly usable thread, irrespective of the percentage engagement. If I'm hand tapping a thru hole I don't use anything other than a taper tap.

Andrew

To the chap having trouble threading the brass tube, it may be the brass which is the problem. Some brass is very easy to machine, I think it is sold as engraving quality. Some is very ductile and will grab drills and suchlike, I think that it's called cartridge brass. That is the sort that is likely to be used for tube which will be bent, but it would be much harder to thread.

To the chap having trouble threading the brass tube, it may be the brass which is the problem. Some brass is very easy to machine, I think it is sold as engraving quality. Some is very ductile and will grab drills and suchlike, I think that it's called cartridge brass. That is the sort that is likely to be used for tube which will be bent, but it would be much harder to thread.