Why 5.5mm Sds drill bit?

[davida...@gmail.com]

Hi
I have often used 5mm and 6mm non-SDS drill bits for rawl plug holes. I am thinking of buying a set of SDS drill bits and have noticed that sets usually include a 5.5mm bit. What is the reason for this size?

David

[Andy Burns]

davida...@gmail.com wrote:

> I am thinking of buying a set of SDS drill bits and have noticed that
> sets usually include a 5.5mm bit. What is the reason for this size?

I think 5.5mm is the 'official' size for red rawlplugs, probably
originally from 7/32"

[Andrew Gabriel]

In article <9K-dnSoBI6sHfNLJ...@brightview.co.uk>,

In many materials, SDS bits end up with a wider hole than the same
size non-SDS bit. With SDS, I will almost always use a smaller bit
than I would have with a plain hammer drill. If the hole is too
tight, I will then widen it with the next bit size up, but not
operating in hammer mode. This gives a cleaner and stronger hole
for supporting rawl plugs.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

[michael adams]

<davida...@gmail.com> wrote in message
news:67f1a700-fd3f-47c1...@googlegroups.com...

Flexibility? As 5mm and 6mm are the probably most popular sizes
an intermediate size offers the possibility of using a 6mm plug
with a thinner but longer screw which would be too long
for a standard 5mm plug. So it offers more purchase on the
actual plug. Also if the walls are a bit on the ropey side I've
often found it can be a help to use bits which are a bit
undersize in any case. The eventual size of the holes
is another matter.


michael adams

...

[Roger Mills]

It's my drill of choice when drilling holes in most materials for red
rawlplugs. I only use 6mm if drilling into something very hard -
concrete or engineering bricks. I get a much firmer fixing that way.
--
Cheers,
Roger
____________
Please reply to Newsgroup. Whilst email address is valid, it is seldom
checked.

[ARW]

"Andrew Gabriel" <and...@cucumber.demon.co.uk> wrote in message
news:m2onup$v0l$2...@dont-email.me...

> In article <9K-dnSoBI6sHfNLJ...@brightview.co.uk>,
> Andy Burns <usenet....@adslpipe.co.uk> writes:
>> davida...@gmail.com wrote:
>>
>>> I am thinking of buying a set of SDS drill bits and have noticed that
>>> sets usually include a 5.5mm bit. What is the reason for this size?
>>
>> I think 5.5mm is the 'official' size for red rawlplugs, probably
>> originally from 7/32"
>
> In many materials, SDS bits end up with a wider hole than the same
> size non-SDS bit.

That's what the brown rawl plugs are for;-)

--
Adam

[Lobster]

On 28 Oct 2014, Andy Burns <usenet....@adslpipe.co.uk> grunted:

My yellow plugs say "5/5.5 mm" and I do tend to use both, depending on
substrate generally.

--
David

[Mike Barnes]

I have to hand some "Woodworkers" brand that say 5.5 mm and some Rawl
brand that say 6 mm.

--
Mike Barnes
Cheshire, England

[fred]

In article <m2onup$v0l$2...@dont-email.me>, Andrew Gabriel
<and...@cucumber.demon.co.uk> writes

I always use a pilot hole, more so for old school hammer drilling than
SDS as the former will more likely take longer and so has a greater
chance to wander.

It's mainly (soft) sandstone here so it makes sense to drill a pilot and
then give it a single run down with the right size bit.

Despite my favourite plugs 'requiring' a 7mm bit, I don't own one but
know just how much wiggle to apply to turn a 6 into a 7.

--
fred
it's a ba-na-na . . . .

[Malcolm Race]

On 28/10/2014 19:35, Roger Mills wrote:
> On 28/10/2014 18:27, davida...@gmail.com wrote:
>> Hi
>> I have often used 5mm and 6mm non-SDS drill bits for rawl plug holes.
>> I am thinking of buying a set of SDS drill bits and have noticed that
>> sets usually include a 5.5mm bit. What is the reason for this size?
>>
>> David
>
> It's my drill of choice when drilling holes in most materials for red
> rawlplugs. I only use 6mm if drilling into something very hard -
> concrete or engineering bricks. I get a much firmer fixing that way.

+1
In softer substrates an SDS bit will tend to make a slightly larger
hole. I always use a 5.5 drill bit for a red rawlplug. In harder
maretials a hammer is needed to insert the plug (4.. screw)
Malcolm

[c...@isbd.net]

Roger Mills <watt....@gmail.com> wrote:
> On 28/10/2014 18:27, davida...@gmail.com wrote:
> > Hi
> > I have often used 5mm and 6mm non-SDS drill bits for rawl plug holes.
> I am thinking of buying a set of SDS drill bits and have noticed that sets
> usually include a 5.5mm bit. What is the reason for this size?
> >
> > David
>
> It's my drill of choice when drilling holes in most materials for red
> rawlplugs. I only use 6mm if drilling into something very hard -
> concrete or engineering bricks. I get a much firmer fixing that way.

Yes, I find the 'recommended' drill sizes for plugs are nearly always
too generous. I'm happiest when I just have to tap the plug in gently
with a hammer (or something else when I've not got a hammer!).

--
Chris Green
·

[c...@isbd.net]

I have some 4mm and 4.5mm SDS bits which I find *very* useful for
yellow plugs to get a nice tight fit. It's very rarely I find that I
actually need to run a 5mm into the hole to get a yellow plug in.

--
Chris Green
·

[Mike Barnes]

c...@isbd.net wrote:
> I find the 'recommended' drill sizes for plugs are nearly always
> too generous. I'm happiest when I just have to tap the plug in gently
> with a hammer (or something else when I've not got a hammer!).

I often use the back of the drill.

[The Medway Handyman]

On 29/10/2014 07:32, Mike Barnes wrote:
> c...@isbd.net wrote:
>> I find the 'recommended' drill sizes for plugs are nearly always
>> too generous. I'm happiest when I just have to tap the plug in gently
>> with a hammer (or something else when I've not got a hammer!).
>
> I often use the back of the drill.
>

+1 :-)


--
Dave - The Medway Handyman www.medwayhandyman.co.uk

[Dave Plowman (News)]

In article <67f1a700-fd3f-47c1...@googlegroups.com>,

It's the 'old' Number 10.

--
*A bartender is just a pharmacist with a limited inventory.

Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.

[Roger Mills]

I find that with 5.5 in harder materials, plastic plugs often buckle
when you try to hammer them in. That's when I use 6mm instead.

[Davey]

I wanted a 7mm bit the other day, and the newly-opened hardware shop in
town didn't have one. Their supplier listed .....5.0, 5.5, 6.0,
8.0, ...... Needless to say, I went to the builder's merchant over the
road, and bought what I needed.

--
Davey.

[harryagain]

<davida...@gmail.com> wrote in message
news:67f1a700-fd3f-47c1...@googlegroups.com...

There is a unique problem to SDS bits.
When the front of the bit goes blunt (esp the small sized), it still drills
fine with the SDS drill (though and ordinary pistol drill wouldn't make any
hole with it.)

But as the side of the drill also wear, you get undersized holes, sometimes
greatly undersized.
This can be a problem you can't resolve by sharpening.
So you end up using the worn drills for the "next size down".

[Dave Plowman (News)]

In article <m2rclb$n9j$2...@dont-email.me>,

harryagain <harry...@btinternet.com> wrote:
> There is a unique problem to SDS bits. When the front of the bit goes
> blunt (esp the small sized), it still drills fine with the SDS drill
> (though and ordinary pistol drill wouldn't make any hole with it.)

You use SDS bits in an 'ordinary pistol drill'?

> But as the side of the drill also wear, you get undersized holes,
> sometimes greatly undersized.

All the masonry bits I've seen have a much wider tip than shank.

> This can be a problem you can't resolve
> by sharpening. So you end up using the worn drills for the "next size
> down".

Or simply buy a new one? SDS drills tend to have a very long life.

--
*Elephants are the only mammals that can't jump *

[charles]

In article <545e707...@davenoise.co.uk>,

Dave Plowman (News) <da...@davenoise.co.uk> wrote:
> In article <m2rclb$n9j$2...@dont-email.me>,
> harryagain <harry...@btinternet.com> wrote:
> > There is a unique problem to SDS bits. When the front of the bit goes
> > blunt (esp the small sized), it still drills fine with the SDS drill
> > (though and ordinary pistol drill wouldn't make any hole with it.)

> You use SDS bits in an 'ordinary pistol drill'?

> > But as the side of the drill also wear, you get undersized holes,
> > sometimes greatly undersized.

> All the masonry bits I've seen have a much wider tip than shank.

> > This can be a problem you can't resolve
> > by sharpening. So you end up using the worn drills for the "next size
> > down".

> Or simply buy a new one? SDS drills tend to have a very long life.

but when you meet a reinforcing rod in a concrete beam, they don't like it.

--
From KT24

Using a RISC OS computer running v5.18

[Andrew Gabriel]

In article <545e8dce...@charleshope.demon.co.uk>,

charles <cha...@charleshope.demon.co.uk> writes:
> but when you meet a reinforcing rod in a concrete beam, they don't like it.

IME, they go straight through rebar without hesitation.
That's not necessarly a good thing - many pre-stressed concrete
lintels only have one rebar in them in the first place.

[charles]

In article <m2ttdf$das$1...@dont-email.me>,

Andrew Gabriel <and...@cucumber.demon.co.uk> wrote:
> In article <545e8dce...@charleshope.demon.co.uk>,
> charles <cha...@charleshope.demon.co.uk> writes:
> > but when you meet a reinforcing rod in a concrete beam, they don't like it.

> IME, they go straight through rebar without hesitation.
> That's not necessarly a good thing - many pre-stressed concrete
> lintels only have one rebar in them in the first place.

oh, I agree they go through, but they aren't much good on brickwork
afterwards.

[Grimly Curmudgeon]

On Tue, 28 Oct 2014 11:27:33 -0700 (PDT), davida...@gmail.com
wrote:

>I have often used 5mm and 6mm non-SDS drill bits for rawl plug holes. I am thinking of buying a set of SDS drill bits and have noticed that sets usually include a 5.5mm bit. What is the reason for this size?

For the slightly smaller 5.5mm frame fixers that sparks commonly use
to bosh in wiring boxes with.

[The Medway Handyman]

On 29/10/2014 08:26, harryagain wrote:
> <davida...@gmail.com> wrote in message
> news:67f1a700-fd3f-47c1...@googlegroups.com...
>> Hi
>> I have often used 5mm and 6mm non-SDS drill bits for rawl plug holes. I am
>> thinking of buying a set of SDS drill bits and have noticed that sets
>> usually include a 5.5mm bit. What is the reason for this size?
>
> There is a unique problem to SDS bits.
> When the front of the bit goes blunt (esp the small sized), it still drills
> fine with the SDS drill (though and ordinary pistol drill wouldn't make any
> hole with it.)
>
> But as the side of the drill also wear, you get undersized holes, sometimes
> greatly undersized.

Utter cobblers. The spiral 'side' of the bit only clears the waste, the
tip makes the hole.

I've never had an SDS bit go blunt, despite drill thousands of holes a year.

[rick]

yep .. most of my plugs take 5.5 ... though I will often drill out at
5.0 to allow for usual loose hole that results.

[Andrew Mawson]

"The Medway Handyman" wrote in message
news:DYH4w.592857$9R5....@fx29.am4...

Dave, I wish that my larger SDS bits were as long lasting as yours seem to
be. I have a box of 20 mm to 35 mm sds drill bits that have been used many
times on re-inforced concrete and are decidedly smooth where they should be
sharp :) Sharpening is easy enough on a diamond or green grit wheel but it's
one of many 'round-tuit' jobs !

I agree with your comment about the spiral having no part in the cutting - I
have some that are amazingly wasted down !

Andrew

[Dave Plowman (News)]

In article <DYH4w.592857$9R5....@fx29.am4>,

The Medway Handyman <davi...@blueyonder.co.uk> wrote:
> I've never had an SDS bit go blunt, despite drill thousands of holes a
> year.

I'd agree - although they don't get anything like your sort of use here.
Ordinary masonry bits in a hammer drill were a different matter.

--
*Hard work pays off in the future. Laziness pays off now *

[Mike Barnes]

The Medway Handyman wrote:
> I've never had an SDS bit go blunt, despite drill thousands of holes a year.

IKWYM but I'd say they do go blunt. But they still work well enough when
blunt, in a way that simple twist bits and masonry bits don't.

[Dave Plowman (News)]

In article <cbhb2g...@mid.individual.net>,

Mike Barnes <mikeba...@gmail.com> wrote:
> The Medway Handyman wrote:
> > I've never had an SDS bit go blunt, despite drill thousands of holes a
> > year.

> IKWYM but I'd say they do go blunt. But they still work well enough when
> blunt, in a way that simple twist bits and masonry bits don't.

It's very easy to check for wear on the tip. And it takes a lot of use
before it shows - although obviously depending on what you're drilling.

--
*Cover me. I'm changing lanes.

[Grimly Curmudgeon]

On Fri, 31 Oct 2014 08:43:17 +0000, The Medway Handyman
<davi...@blueyonder.co.uk> wrote:

>> But as the side of the drill also wear, you get undersized holes, sometimes
>> greatly undersized.
>
>Utter cobblers. The spiral 'side' of the bit only clears the waste, the
>tip makes the hole.
>
>I've never had an SDS bit go blunt, despite drill thousands of holes a year.

You must have one of the fabled everlasting drill bits, then.
I keep getting the ones that eventually wear - and I've also drilled
thousands of holes with them.

[Roger Chapman]

I suppose it depends to a great extent on what you are drilling into.
When I moved to my current address in 1978 my trusty hammer drill would
take 10 minutes or more to drill a hole for a wall plug in the stone
walls even assuming the masonry drill stood up to the punishment. SDS of
course is a different ball game but the drill bits tend not to last. I
don't actually count the number of holes I drill but I suspect that my
drills last for 100s of holes rather than 1000s. And if you can drill a
small diameter hole in a few seconds you do tend to drill far more holes
than you would if almost every hole was an epic as used to be the case.

--
Roger Chapman

[charles]

In article <m42ds4$9kc$1...@speranza.aioe.org>, Roger Chapman

<Ro...@nospam.btinternet.com> wrote:
> On 13/11/2014 13:40, Grimly Curmudgeon wrote:
> > On Fri, 31 Oct 2014 08:43:17 +0000, The Medway Handyman
> > <davi...@blueyonder.co.uk> wrote:
> >
> >>> But as the side of the drill also wear, you get undersized holes,
> >>> sometimes greatly undersized.
> >>
> >> Utter cobblers. The spiral 'side' of the bit only clears the waste,
> >> the tip makes the hole.
> >>
> >> I've never had an SDS bit go blunt, despite drill thousands of holes a
> >> year.
> >
> > You must have one of the fabled everlasting drill bits, then. I keep
> > getting the ones that eventually wear - and I've also drilled thousands
> > of holes with them.
> >
> I suppose it depends to a great extent on what you are drilling into.
> When I moved to my current address in 1978 my trusty hammer drill would
> take 10 minutes or more to drill a hole for a wall plug in the stone
> walls even assuming the masonry drill stood up to the punishment.

and before masonry drills we had to use a Rawltool!

[meow...@care2.com]

On Tuesday, October 28, 2014 6:40:35 PM UTC, Andrew Gabriel wrote:
> In article <9K-dnSoBI6sHfNLJ...@brightview.co.uk>,
> Andy Burns <usenet....@adslpipe.co.uk> writes:
> > davida...@gmail.com wrote:
> >

> >> I am thinking of buying a set of SDS drill bits and have noticed that
> >> sets usually include a 5.5mm bit. What is the reason for this size?
> >

> > I think 5.5mm is the 'official' size for red rawlplugs, probably
> > originally from 7/32"
>

> In many materials, SDS bits end up with a wider hole than the same
> size non-SDS bit. With SDS, I will almost always use a smaller bit
> than I would have with a plain hammer drill. If the hole is too
> tight, I will then widen it with the next bit size up, but not
> operating in hammer mode. This gives a cleaner and stronger hole
> for supporting rawl plugs.

+1. If its then not tight enough, stick a match in the plug.


NT

[Capitol]

and before that, we used a piece of pipe with the end notched and a
club hammer! Great fun on 6' thick walls.

[stuart noble]

Do you carry a box of matches? I light my joints with a blowtorch

[Grimly Curmudgeon]

On Thu, 13 Nov 2014 14:06:02 +0000, Roger Chapman
<Ro...@nospam.btinternet.com> wrote:

>> You must have one of the fabled everlasting drill bits, then.
>> I keep getting the ones that eventually wear - and I've also drilled
>> thousands of holes with them.
>>
>I suppose it depends to a great extent on what you are drilling into.
>When I moved to my current address in 1978 my trusty hammer drill would
>take 10 minutes or more to drill a hole for a wall plug in the stone
>walls even assuming the masonry drill stood up to the punishment. SDS of
>course is a different ball game but the drill bits tend not to last. I
>don't actually count the number of holes I drill but I suspect that my
>drills last for 100s of holes rather than 1000s. And if you can drill a
>small diameter hole in a few seconds you do tend to drill far more holes
>than you would if almost every hole was an epic as used to be the case.

I lost a 14mm SDS bit the other day. It went in and jammed solid and
as it was at the top of a section of ladder I wasn't in a position to
get decent access or leverage on it. Fortunately the hole wasn't a
vital one-off position, so a new hole got drilled below it and the
first new proper application of my new AG took place on the stuck bit.

[fred]

Axminster recommend 5.5mm bits for their red wall plugs