Bought a pack of 3 400mm long "masonry" drill bits to use as pilot for drilling
a 20mm hole for outside tap. Each drill completly wore the red tip down to
nothing in about half inch drilling of a crap scottish brick.
Guess I will have to spend more than a pound on a set...

Geo

"Geo" wrote in message
...
Bought a pack of 3 400mm long "masonry" drill bits to use as pilot for
drilling
a 20mm hole for outside tap. Each drill completly wore the red tip down to
nothing in about half inch drilling of a crap scottish brick.
Guess I will have to spend more than a pound on a set...

Geo

Don't feel too bad. I just bought a set of 3 1000mm SDS drills for £19...
they might last a couple of holes each.

a 20mm hole for outside tap. Each drill completly wore the red tip down to
nothing in about half inch drilling of a crap scottish brick.
Guess I will have to spend more than a pound on a set...

Cue for Scottish jokes....

Seriously though, some of the cheap masonry drills seem fine and some are
rubbish. Name and Shame!

Steve

On Fri, 29 Apr 2005 20:14:00 +0100, "Newshound"
wrote:

Cue for Scottish jokes....

Seriously though, some of the cheap masonry drills seem fine and some are
rubbish. Name and Shame!

OK - from the Pound Shop in Falkirk, Blackspur Tools 3Pc 400mm Masonry Drill Set
- tips reduced to rounded lumps in 30 seconds...
Geo

Geo wrote:
On Fri, 29 Apr 2005 20:14:00 +0100, "Newshound"
wrote:


Cue for Scottish jokes....

Seriously though, some of the cheap masonry drills seem fine and some are
rubbish. Name and Shame!


OK - from the Pound Shop in Falkirk, Blackspur Tools 3Pc 400mm Masonry Drill Set
- tips reduced to rounded lumps in 30 seconds...
Geo

Blackspur!! (clenches fist and spits)
I bought a pack of 6 flat bits from a cheap shop in Liverpool.
I had to power the drill in reverse to make a hole.

Arthur

In article ,
Arthur writes:
Geo wrote:

OK - from the Pound Shop in Falkirk, Blackspur Tools 3Pc 400mm Masonry Drill Set
- tips reduced to rounded lumps in 30 seconds...
Geo

Blackspur!! (clenches fist and spits)

Sounds like a special brand for cowboys...

I bought a pack of 6 flat bits from a cheap shop in Liverpool.
I had to power the drill in reverse to make a hole.

--
Andrew Gabriel

Made in China,will we ever learn,buy cheap gets cheap

TonyK wrote:

"Geo" wrote in message
.. .
Bought a pack of 3 400mm long "masonry" drill bits to use as pilot for
drilling
a 20mm hole for outside tap. Each drill completly wore the red tip down to
nothing in about half inch drilling of a crap scottish brick.
Guess I will have to spend more than a pound on a set...

Geo

Don't feel too bad. I just bought a set of 3 1000mm SDS drills for £19...
they might last a couple of holes each.


No problem here with a 10x1000mm from Screwfix. After a whole afternoon
of probing into Scottish bedrock (trying to find somewhere to sink an
earth rod), it happily drilled through three layers of engineering
brick. The tip still isn't showing much wear.


--
Ian White

In article ,
TonyK wrote:
Don't feel too bad. I just bought a set of 3 1000mm SDS drills for £19...
they might last a couple of holes each.

SDS tends to be far kinder on the bits than hammer. It's the heat that
kills them.

--
*Am I ambivalent? Well, yes and no.

Dave Plowman London SW
To e-mail, change noise into sound.

Geo wrote:
On Fri, 29 Apr 2005 20:14:00 +0100, "Newshound"


Seriously though, some of the cheap masonry drills seem fine and
some are
rubbish. Name and Shame!

OK - from the Pound Shop in Falkirk, Blackspur Tools 3Pc 400mm
Masonry Drill Set
- tips reduced to rounded lumps in 30 seconds...
Geo

Ah, Blackspur... its ancient Saxon and means 'beware, you wont even get
one job done with this POS.'

I bought Blackspur screwdriver whatnots. Managed one screw. The screw
head was fine, but the driver had acquired a new shape altogether.


NT

Ah, Blackspur... its ancient Saxon and means 'beware, you wont even get
one job done with this POS.'

I bought Blackspur screwdriver whatnots. Managed one screw. The screw
head was fine, but the driver had acquired a new shape altogether.

Suppose it's horses for courses. Only Blackspur thing I ever bought were
some clamps - they work like a sealant gun - don't know the proper name.
They work an absolute treat, better than some more expensive ones I have.

Dave

Geo wrote:

OK - from the Pound Shop in Falkirk, Blackspur Tools 3Pc 400mm
Masonry Drill Set
- tips reduced to rounded lumps in 30 seconds...
Geo

Got an angle grinder? Cut slots in them and dip in water to harden,
drill another half inch, cut em again and dip in water, etc etc etc.

Crude, but sometimes it can be quicker than going to the shops.

I was going to say it might just be theyre being overheated and need
more rest, but probably not: my experience of blackspur work bits is no
hardening at all, and quite useless. In which case grinding and dipping
might make them last better.


NT

Geo wrote:
On Fri, 29 Apr 2005 20:14:00 +0100, "Newshound"
wrote:
OK - from the Pound Shop in Falkirk, Blackspur Tools 3Pc 400mm Masonry Drill Set
- tips reduced to rounded lumps in 30 seconds...
Geo
Would heating them red hot on the stove then quenching them in water be
of benefit?

---
Adrian

Adrian C wrote:

Would heating them red hot on the stove then quenching them in water be
of benefit?

That is how you would normally soften hardened metal... it this case it
sounds like it is not going to get much softer ;-)


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

TonyK wrote:

"Geo" wrote in message
...
Bought a pack of 3 400mm long "masonry" drill bits to use as pilot for
drilling
a 20mm hole for outside tap. Each drill completly wore the red tip down to
nothing in about half inch drilling of a crap scottish brick.
Guess I will have to spend more than a pound on a set...

Geo

Don't feel too bad. I just bought a set of 3 1000mm SDS drills for ?19...
they might last a couple of holes each.

Or maybe not.
Bought a set of 3*1000mm (8,15,122mm) and the 22mm bit has done about
30*8" holes in concrete and 10*8" in granite (to punch a hole through a
concrete slab to run cabling)

No perceptible wear.

John Rumm wrote :-

Adrian C wrote:

Would heating them red hot on the stove then quenching them in water be
of benefit?

That is how you would normally soften hardened metal... it this case it
sounds like it is not going to get much softer ;-)

Nope, to soften you normally allow to cool very slowly

Regards Jeff

Dave Plowman (News) wrote :-

SDS tends to be far kinder on the bits than hammer. It's the heat that
kills them.

Years ago I had a B&D drill that had a switch for the 2 speeds, 3300 and
2800 iirc both far too fast for masonry drill bits, it used to burn 'em out
rapidly.
I had a very frustrating time fitting a 4" fan in quite hard bricks.
Slow, 900 rpm is the answer or better still SDS

Regards Jeff

Jeff wrote:

That is how you would normally soften hardened metal... it this case it
sounds like it is not going to get much softer ;-)


Nope, to soften you normally allow to cool very slowly

Not with ferrous metals IIRC.

(slow cooling will anneal copper for example, but quenching works better
on steel)


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

John Rumm wrote :-

That is how you would normally soften hardened metal... it this case it
sounds like it is not going to get much softer ;-)


Nope, to soften you normally allow to cool very slowly

Not with ferrous metals IIRC.

(slow cooling will anneal copper for example, but quenching works better
on steel)

I beg to differ my good man :-

To harden most steel it is heated to a medium red or slightly above the
point where it becomes non-magnetic. It is then quenched in water, oil or
air depending on the type of steel. The steel is now at its maximum hardness
but is very brittle. To reduce the brittleness the metal is tempered by
heating it to some where between 350°F and 1350°F. This reduced the hardness
a little and the brittelness a lot. Most steels need to be tempered at about
450°F for maximum usable hardness but every steel is slightly different.
To soften steel so that it can be cold worked and machined is called
annealing. To anneal steel is is heated to slightly above the hardening
temperature and then cooled as slow as possible. Cooling is done in an
insulating medium such as dry powdered lime or in vermiculite. High carbon
and many alloy steels can only be cooled slow enough in a temperatue
controlled furnace since the cooling rate must be only 20 degrees F per hour
for several hours.

source = http://www.anvilfire.com/FAQs/heat_faq_index.htm

I don't remember much from school but I do remember annealling aluminium and
hardening steel + have done a bit of case hardening over the years

Regards Jeff

Hi John
Not with ferrous metals IIRC.

(slow cooling will anneal copper for example, but quenching works better
on steel)

But surely on a masonry drill bit we are talking about tungsten carbide and
not ordinary steel?

Dave

Jeff wrote:

I beg to differ my good man :-

In which case I stand corrected... ;-)

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

Adrian C wrote:
Geo wrote:

On Fri, 29 Apr 2005 20:14:00 +0100, "Newshound"

wrote:
OK - from the Pound Shop in Falkirk, Blackspur Tools 3Pc 400mm Masonry
Drill Set
- tips reduced to rounded lumps in 30 seconds...
Geo

Would heating them red hot on the stove then quenching them in water be
of benefit?


At that temerarure, the tips would fall off due to the brazed joints
melting.

Dave

Adrian C wrote:
Geo wrote:

On Fri, 29 Apr 2005 20:14:00 +0100, "Newshound"

wrote:
OK - from the Pound Shop in Falkirk, Blackspur Tools 3Pc 400mm Masonry
Drill Set
- tips reduced to rounded lumps in 30 seconds...
Geo

Would heating them red hot on the stove then quenching them in water be
of benefit?

---
Adrian

From my days as an App' more than 25 years ago.
Mild steel is a low carbon steel that can only be case hardened.
Case hardening is a process of heating to erm red hot and immersing the
steel in a carbon powder for some time.
High carbon steels can be hardened by heating to red hot and then rapid
cooling by quenching in water.
This treatment would not make the steel suitable for driiling for
example because the steel would be too brittle.
To achieve the optimum hardness for a particular function eg, steel
cutting, drilling, scraping, spring, etc.
the steel must be Annealed/Temprered by heating and quenching
This is process of reheating to a particular temperature measured by
monitoring the colour of the steel as it is heated,
dark straw,
straw,
yellow,
,
,
blue,
dark blue
...then immediately quenching again at the required colour.

Normalising is another process of heating and then cooling naturally.
This is done to usually mild steel if it has undergone various streeses.
eg, bending. Bending a piece of steel or copper will cause weakness to
the bend area. Normalising will restore the area to its original state
and minimise weak spots.

I hope my memory has served me well and proves to be helpful to some.

Arthur

On Sun, 01 May 2005 20:39:16 GMT, "David Lang"
wrote:

But surely on a masonry drill bit we are talking about tungsten carbide and
not ordinary steel?

I have my doubts about the red-painted tips being anything special at all...
"After" photo (150k) at www.lintech.pwp.blueyonder.co.uk/drills.jpg/
Geo

Geo wrote:
"David Lang" wrote:
But surely on a masonry drill bit we are talking about tungsten carbide and
not ordinary steel?

I have my doubts about the red-painted tips being anything special at all...
"After" photo (150k) at www.lintech.pwp.blueyonder.co.uk/drills.jpg/

Could be TCT bits, this can happen with bits that have a thin section
of TC at the tip, and too much feed has been applied, or where the bits
have been cooled too rapidly (even during manufacture). Pieces of TC
flake off in the hole & cause extremely fast self-destruction of the
remaining piece. A "before" picture would be interesting...