Hello -

I'd like to create a few M4 or M5 threaded holes in some pieces of brass and
aluminium that I've got. Ideally the holes should be about 8mm deep and
blind, not "all the way through". I've never used a tap or die, but this
seems like a good excuse to add to my tool collection have have a play.

Is buying a cheap set such as
http://www.screwfix.com/app/sfd/cat/...12080&ts=39681 in order to
gain experience a good plan? Are the eye-wateringly expensive sets that RS
sell necessary for DIY use? Is it worth buying a set that includes drill
bits in the exact sizes needed, eg 3.2mm, or will drill bits in 0.5mm
intervals be OK?

Thanks

"Simon" wrote in message
...
Hello -

I'd like to create a few M4 or M5 threaded holes in some pieces of brass
and
aluminium that I've got. Ideally the holes should be about 8mm deep and
blind, not "all the way through". I've never used a tap or die, but this
seems like a good excuse to add to my tool collection have have a play.

Is buying a cheap set such as
http://www.screwfix.com/app/sfd/cat/...12080&ts=39681 in order to
gain experience a good plan? Are the eye-wateringly expensive sets that RS
sell necessary for DIY use? Is it worth buying a set that includes drill
bits in the exact sizes needed, eg 3.2mm, or will drill bits in 0.5mm
intervals be OK?

Thanks



You really need the correct drill size otherwise the thread may be too
shallow (over truncated)

Simon wrote:
Hello -

I'd like to create a few M4 or M5 threaded holes in some pieces of brass and
aluminium that I've got. Ideally the holes should be about 8mm deep and
blind, not "all the way through". I've never used a tap or die, but this
seems like a good excuse to add to my tool collection have have a play.

Is buying a cheap set such as
http://www.screwfix.com/app/sfd/cat/...12080&ts=39681 in order to
gain experience a good plan? Are the eye-wateringly expensive sets that RS
sell necessary for DIY use? Is it worth buying a set that includes drill
bits in the exact sizes needed, eg 3.2mm, or will drill bits in 0.5mm
intervals be OK?


halfords do a reasonable mixed set, as do machine Mart... if you
know you will only want M4 & M5 then go to a trade tool outlet and but
the size you want ...
You need 2 taps per size Taper & Plug (or bottoming) then
importantly you need the right size drill .... for M5 you need a
4.2mm drill for M4 it would be 3.3mm
Yes you can buy what may seem odd sizes ... I have a 2 drill sets
providing 0.1mm to 20mm in 0.1mm increments.

Although as you are going into soft material, go to nearest size down,
and take your time, clear out swarf frequently.

Depends on if this is a one off job or not.

Simon wrote:
Hello -

I'd like to create a few M4 or M5 threaded holes in some pieces of brass and
aluminium that I've got. Ideally the holes should be about 8mm deep and
blind, not "all the way through". I've never used a tap or die, but this
seems like a good excuse to add to my tool collection have have a play.

Is buying a cheap set such as
http://www.screwfix.com/app/sfd/cat/...12080&ts=39681 in order to
gain experience a good plan? Are the eye-wateringly expensive sets that RS
sell necessary for DIY use? Is it worth buying a set that includes drill
bits in the exact sizes needed, eg 3.2mm, or will drill bits in 0.5mm
intervals be OK?

Thanks



The set you point to has only taper taps. The problem is that you want
to tap blind holes, so you need both taper and plug taps (the plug tap
cuts the last few threads parallel at the bottom of the hole) otherwise
the tapings will tighten up as you screw in the bolt. Better still a
taper, second, and plug.

See http://www.axminster.co.uk/recno/3/p...arse-23493.htm

If you want to do just M4 and M5, you would be advised to buy just those
sizes of good quality taps, and the corresponding correct drills.

Most brass doesn't need a lubricant (IIRC), but I think aluminium does,
but I can't remember what it should be.

The trick is to go very slowly, and back out a little very often to
break and clear the swarf. You can get a rhythm going.

R.

"Richard Downing" wrote in message
...
Simon wrote:
Hello -

I'd like to create a few M4 or M5 threaded holes in some pieces of brass
and
aluminium that I've got. Ideally the holes should be about 8mm deep and
blind, not "all the way through". I've never used a tap or die, but this
seems like a good excuse to add to my tool collection have have a play.

Is buying a cheap set such as
http://www.screwfix.com/app/sfd/cat/...12080&ts=39681 in order to
gain experience a good plan? Are the eye-wateringly expensive sets that
RS
sell necessary for DIY use? Is it worth buying a set that includes drill
bits in the exact sizes needed, eg 3.2mm, or will drill bits in 0.5mm
intervals be OK?

Thanks



The set you point to has only taper taps. The problem is that you want to
tap blind holes, so you need both taper and plug taps (the plug tap cuts
the last few threads parallel at the bottom of the hole) otherwise the
tapings will tighten up as you screw in the bolt. Better still a taper,
second, and plug.

See
http://www.axminster.co.uk/recno/3/p...arse-23493.htm

If you want to do just M4 and M5, you would be advised to buy just those
sizes of good quality taps, and the corresponding correct drills.

Most brass doesn't need a lubricant (IIRC), but I think aluminium does,
but I can't remember what it should be.

The trick is to go very slowly, and back out a little very often to break
and clear the swarf. You can get a rhythm going.

R.

Is it paraffin ?

The set you point to has only taper taps. The problem is that you want
to tap blind holes, so you need both taper and plug taps (the plug tap
cuts the last few threads parallel at the bottom of the hole) otherwise
the tapings will tighten up as you screw in the bolt. Better still a
taper, second, and plug.

See http://www.axminster.co.uk/recno/3/p...arse-23493.htm

If you want to do just M4 and M5, you would be advised to buy just those
sizes of good quality taps, and the corresponding correct drills.

Most brass doesn't need a lubricant (IIRC), but I think aluminium does,
but I can't remember what it should be.

The trick is to go very slowly, and back out a little very often to
break and clear the swarf. You can get a rhythm going.



Don't bother with expense of looking for a set with a second tap ...
unnecessary, I have never had to use one, and threaded hundreds of
holes in just about all materials ... a taper & plug are what you need.
Use some white spirit as the lubricant, and follow advice by previous
poster .. slowly doe sit.

The message .com
from "Osprey" contains these words:

Use some white spirit as the lubricant, and follow advice by previous
poster .. slowly doe sit.

Mostly it's down to technique. Forward till it starts to get tight, then
back off to clear the swarf, then forward till it starts to get
tight....

If you try to just bang the tap straight down the hole you'll end up in
trouble.

--
Skipweasel
Pay no attention to that man behind the curtain.

"Simon" wrote in message
...
Hello -

I'd like to create a few M4 or M5 threaded holes in some pieces of brass
and
aluminium that I've got. Ideally the holes should be about 8mm deep and
blind, not "all the way through". I've never used a tap or die, but this
seems like a good excuse to add to my tool collection have have a play.

Is buying a cheap set such as
http://www.screwfix.com/app/sfd/cat/...12080&ts=39681 in order to
gain experience a good plan?

Cheap tools are almost never a good idea. In any case, that set seems to
provide only one tap per size, probably a taper tap, and they are thread
cutting taps. For any blind hole you need, as a miniumum, a taper and a plug
tap, preferably taper, second and plug taps. While cutting taps will work
fine with brass, they are not the best choice for aluminium. For that, you
need lobed taps, which distort the aluminium into the thread form, without
cutting, and the associated work hardening makes the thread much stronger.

Are the eye-wateringly expensive sets that RS
sell necessary for DIY use?

Best is to go to an Engineers' Supplier, or a real specialist, like Drill
Services (Horley) Ltd.

Is it worth buying a set that includes drill
bits in the exact sizes needed, eg 3.2mm, or will drill bits in 0.5mm
intervals be OK?

You should always have the right size tapping drills. Undersize pilot holes
make tapping difficult and may lead to breaking the tap. Oversized pilot
holes reduce the depth of thread, making it more likely you will strip the
thread when tightening something into it.

Colin Bignell

On Mon, 12 Jun 2006 20:25:20 +0100, "Simon"
wrote:

I'd like to create a few M4 or M5 threaded holes in some pieces of brass and
aluminium that I've got.

Is buying a cheap set such as
http://www.screwfix.com/app/sfd/cat/...12080&ts=39681 in order to
gain experience a good plan?

Probably not - certainly not if you know the sizes beforehand and you
only need a couple of sizes.

It _might_ be useful for Gross Bodgery if things come into the workshop
where you never know what size you'll be needing next. OTOH, the
Screwfix ones are really bad quality and they're metric only. M12 in
carbon steel ? The thing is going to last about an inch, if that much.

Are the eye-wateringly expensive sets that RS sell necessary for DIY use?

Yes. Although you can get them for less than RS' prices.

The simple rules for taps and dies:

Are you now, or have you ever been, a reader of Model Engineer? if you
haven't, then you only need a couple of sets of metrics and you're
sorted forever. You can afford these, even in good quality.

HSS. Carbon steel is a bad joke.

Presto, or similar quality, and made in England (or Europe at least).
Don't waste your time and metal on cheapies.

Almost any amount of effort to avoid breaking a tap is easier than the
trouble of removing a broken one.

Taps. You need taps, not often do you need dies. People without lathes
very rarely need dies.

Taps come in sets of 3 (taper, second, plug), not sets of 2. Real ones,
that is. For small taps then you can manage with only second and plug
quite adequately (no taper) but the 2-tap sets are often somewhere
between "taper-second" and "chamfered plug".

2 fluted taps will break if you bend them sideways. Nearly all very
small taps will be 2 fluted, but get 3 fluted if you possibly can.

Dies are adjustable in size. Set them correctly, or you'll have loose /
tight threads.

A set of Zeus tables is useful, but you can often pick up freebie
equivalents in better toolshop.

There are two metric pitches (for most threads).

Tapping drills are magic sizes. Now drills are cheap, so buy extra
tapping drills just the right size when you get your taps. Keep them
with the taps and don't use them for anything else.

Get a nice tap wrench. Get several, of different sizes. eBay.

Get a squirt bottle of RTD (cutting goop) if you ever tap steel. If
without, then at least use _something_ greasy or oil. Brass often needs
cutting lube to clear the chips away too (back the tap out and wipe it).

Use the right tapping action - two flutes forward, one flute back.
Pretty spirals look nice, but they'll bind and break your tap.

Spiral taps make a great bargain at an auction, but they're machine taps
and there's a reason why few people buy a second one for hand use.

A tapping machine is very useful, especially for fine work in aluminium.
Use a drill press with the belt off and maybe the feed spring unhooked,
at least until you have the thread started square.

If you use the same size over and over, then keep spares on hand.
Particularly M3 !

Andy Dingley wrote:

Taps. You need taps, not often do you need dies. People without lathes
very rarely need dies.


I found dies quite useful for cleaning the threads on slightly buggered
screws, open up the die, spin it down to a good part of the thread,
tighten it up till it just touches, then back it out, often all that is
needed for unusual screw sizes. (or material)

On Mon, 12 Jun 2006 20:25:20 +0100, Simon wrote
(in article ):

Hello -

I'd like to create a few M4 or M5 threaded holes in some pieces of brass and
aluminium that I've got. Ideally the holes should be about 8mm deep and
blind, not "all the way through". I've never used a tap or die, but this
seems like a good excuse to add to my tool collection have have a play.

Is buying a cheap set such as
http://www.screwfix.com/app/sfd/cat/...12080&ts=39681 in order to
gain experience a good plan? Are the eye-wateringly expensive sets that RS
sell necessary for DIY use? Is it worth buying a set that includes drill
bits in the exact sizes needed, eg 3.2mm, or will drill bits in 0.5mm
intervals be OK?

Thanks



Really the equation is what level of quality do you want and whether you can
get it for the price you are willing to pay. That doesn't correlate to
whether the use is DIY or not.

I was looking for a similar thing myself a few months ago, and rejected the
cheap sets that are around because generally they have only one tap per size
which is sometimes not good enough.

Eventually I bought a boxed set from

http://www.tapdie.com/

which has proved to be good quality (i.e. not carbon steel) for just over
£100.

I don't need the longevity of a professional engineer's set costing about
three times the price and more but the accuracy and results have been fine.

Andy Hall wrote:
sometimes not good enough.

Eventually I bought a boxed set from

http://www.tapdie.com/


Good link that

"Simon" wrote in message
...
Hello -

I'd like to create a few M4 or M5 threaded holes in some pieces of brass
and
aluminium that I've got. Ideally the holes should be about 8mm deep and
blind, not "all the way through". I've never used a tap or die, but this
seems like a good excuse to add to my tool collection have have a play.

Is buying a cheap set such as
http://www.screwfix.com/app/sfd/cat/...12080&ts=39681 in order to
gain experience a good plan? Are the eye-wateringly expensive sets that RS
sell necessary for DIY use? Is it worth buying a set that includes drill
bits in the exact sizes needed, eg 3.2mm, or will drill bits in 0.5mm
intervals be OK?

Thanks



I have an RS set and the is good quality and not let me down yet.

I've often used Taptite screws when I've not had a tap to hand, or for
blind holes, work them up and down a few times.

In message , Simon
writes
Hello -

I'd like to create a few M4 or M5 threaded holes in some pieces of brass and
aluminium that I've got. Ideally the holes should be about 8mm deep and
blind, not "all the way through". I've never used a tap or die, but this
seems like a good excuse to add to my tool collection have have a play.

Is buying a cheap set such as
http://www.screwfix.com/app/sfd/cat/...12080&ts=39681 in order to
gain experience a good plan? Are the eye-wateringly expensive sets that RS
sell necessary for DIY use? Is it worth buying a set that includes drill
bits in the exact sizes needed, eg 3.2mm, or will drill bits in 0.5mm
intervals be OK?

Thanks



--
Neil J. Harris