Bargain at B & Q

[Gareth's Downstairs Computer]

Now , I know that we've all got hexagonal screwdriver inserts
coming out of our ears, however ...

For only £20, B & Q have a 250-piece set of metal drills,
masonry drills, wood cutting drills, ordinary (!!) drills,
wood-cutting bits, and some of those pesky screwdriver inserts.

Why is this good? Well, when drilling out a larger hole on the
lathe, I now do not need to risk sacificing my precision drills
to get to the hole size required, for there is a very wide
selection of (apparently) titanium tipped drills from about
1.5mm upwards.

[Clifford Coggin]

Post by Gareth's Downstairs Computer
Now , I know that we've all got hexagonal screwdriver inserts
coming out of our ears, however ...
For only £20, B & Q have a 250-piece set of metal drills,
masonry drills, wood cutting drills, ordinary (!!) drills,
wood-cutting bits, and some of those pesky screwdriver inserts.
Why is this good? Well, when drilling out a larger hole on the
lathe, I now do not need to risk sacificing my precision drills
to get to the hole size required, for there is a very wide
selection of (apparently) titanium tipped drills from about
1.5mm upwards.

At eight pence per bit do you really think Chinesium will drill through
anything more than butter.

[David Billington]

Post by Clifford Coggin

Post by Gareth's Downstairs Computer
Now , I know that we've all got hexagonal screwdriver inserts
coming out of our ears, however ...
For only £20, B & Q have a 250-piece set of metal drills,
masonry drills, wood cutting drills, ordinary (!!) drills,
wood-cutting bits, and some of those pesky screwdriver inserts.
Why is this good? Well, when drilling out a larger hole on the
lathe, I now do not need to risk sacificing my precision drills
to get to the hole size required, for there is a very wide
selection of (apparently) titanium tipped drills from about
1.5mm upwards.

At eight pence per bit do you really think Chinesium will drill
through anything more than butter.

My neighbour gave me some HSS drills he bought from UK Drills in packs
of 10 and he didn't need them all so gave me some. I tried one on some
stainless and the stainless won easily, my Hertel HSS drills dealt with
the stainless easily. I'll keep the cheap ones on the side for soft
stuff like wood and aluminium.

[Brian Reay]

Post by Clifford Coggin

Post by Gareth's Downstairs Computer
Now , I know that we've all got hexagonal screwdriver inserts
coming out of our ears, however ...
For only £20, B & Q have a 250-piece set of metal drills,
masonry drills, wood cutting drills, ordinary (!!) drills,
wood-cutting bits, and some of those pesky screwdriver inserts.
Why is this good? Well, when drilling out a larger hole on the
lathe, I now do not need to risk sacificing my precision drills
to get to the hole size required, for there is a very wide
selection of (apparently) titanium tipped drills from about
1.5mm upwards.

At eight pence per bit do you really think Chinesium will drill through
anything more than butter.

I've been 'pleasantly surprised' by cheap drill bits in the past. I tend
to have a 'good' set which are for more demanding jobs and a cheap set
for run of the mill diy work. The cheap set are typically like those
mentioned.

As is the way with things- sometimes I can't find/don't have/have
broken/etc the drill bit I need for a demanding job and I've used one of
the cheap drills.

They may not 'hold their edge' so well but I don't recall not being able
to drill even stainless steel (which I do occasionally).

All in all, probably not a bad buy- but wait until Wednesday if you are
60 or over ;-)


On a more general point, does anyone know the idea behind having a
titanium coating? It is a metal which seems to be 'popping up' in all
kinds of things. I know it is strong, light etc, but it almost seems to
be 'fashionable' recently. (I like insulted coffee/tea mugs, ideally
metal. My latest addition to my collection is titanium. It is supposed
to have all kinds of 'benefits'- I just liked it and wanted to keep my
coffee/tea hot.)

[Alan Dawes]

Post by Brian Reay
On a more general point, does anyone know the idea behind having a
titanium coating?

That's just advertising speak, they are actually coated with the compound
Titanium Nitride which is harder than steel at 9 on the Mohr (Moh?)scale
just below that of diamond.

Alan

[Brian Reay]

Post by Alan Dawes

Post by Brian Reay
On a more general point, does anyone know the idea behind having a
titanium coating?

That's just advertising speak, they are actually coated with the compound
Titanium Nitride which is harder than steel at 9 on the Mohr (Moh?)scale
just below that of diamond.
Alan

Thank you.

More of a rhetorical question, although someone may know the answer:
Presumably the coated finish is more akin to 'case hardening' that the
hardening and tempering (limited for drills etc) used for tool steels etc.

(As I understand it, case hardening is more of a surface treatment. Heat
treatment and tempering tends to be more than 'skin deep'. )

[Alan Dawes]

Post by Brian Reay

Post by Alan Dawes

Post by Brian Reay
On a more general point, does anyone know the idea behind having a
titanium coating?

That's just advertising speak, they are actually coated with the
compound Titanium Nitride which is harder than steel at 9 on the Mohr
(Moh?)scale just below that of diamond.
Alan

Thank you.
Presumably the coated finish is more akin to 'case hardening' that the
hardening and tempering (limited for drills etc) used for tool steels etc.
(As I understand it, case hardening is more of a surface treatment. Heat
treatment and tempering tends to be more than 'skin deep'. )

I think for drills and milling cutters, it is usually applied by PVD
(Physical Vapour Deposition) as a very thin coating using an electron beam
or by "sputtering" or a cathodic arc to coat very tiny particles of TiN
onto the surface of the steel where they become part of the crystal
structure.

Alan

[Brian Reay]

Post by Alan Dawes

Post by Brian Reay

Post by Alan Dawes

Post by Brian Reay
On a more general point, does anyone know the idea behind having a
titanium coating?

That's just advertising speak, they are actually coated with the
compound Titanium Nitride which is harder than steel at 9 on the Mohr
(Moh?)scale just below that of diamond.
Alan

Thank you.
Presumably the coated finish is more akin to 'case hardening' that the
hardening and tempering (limited for drills etc) used for tool steels etc.
(As I understand it, case hardening is more of a surface treatment. Heat
treatment and tempering tends to be more than 'skin deep'. )

I think for drills and milling cutters, it is usually applied by PVD
(Physical Vapour Deposition) as a very thin coating using an electron beam
or by "sputtering" or a cathodic arc to coat very tiny particles of TiN
onto the surface of the steel where they become part of the crystal
structure.

Interesting, thank you. The end result does sound more akin to case
hardening than a bulk heat treatment then in that there is a thin layer
changed due to an additive. Of course, the nature of the change in the
structure may well be different, just as the additive is.

I remember using case hardening at school when making an adjustable
spanner (which I still have, 40+ years on). We also made screwdrivers
and an ordinary spanner- unfortunately I've lost those.

[RustyHinge]

Post by Brian Reay
Presumably the coated finish is more akin to 'case hardening' that the
hardening and tempering (limited for drills etc) used for tool steels etc.

I think that would depend on how it is bonded to the steel

Post by Brian Reay
(As I understand it, case hardening is more of a surface treatment. Heat
treatment and tempering tends to be more than 'skin deep'.)

It should be 'more than skin-deep'. There is a real art in hardening and
tempering some tools: hammer heads for instance, should be tough on the
inside and hard on the faces - not easy to accomplish.

[Brian Reay]

Post by RustyHinge

Post by Brian Reay
Presumably the coated finish is more akin to 'case hardening' that the
hardening and tempering (limited for drills etc) used for tool steels etc.

I think that would depend on how it is bonded to the steel

That was part of the question.

Post by RustyHinge

Post by Brian Reay
(As I understand it, case hardening is more of a surface treatment.
Heat treatment and tempering tends to be more than 'skin deep'.)

It should be 'more than skin-deep'. There is a real art in hardening and
tempering some tools: hammer heads for instance, should be tough on the
inside and hard on the faces - not easy to accomplish.

Aren't they forged to provide the 'inner' toughness then heat treated to
provide a hard surface.