diamond cutting wheel question
 

I have a Pro Tec 115mm diamond cutting wheel; bought it a couple of days
ago for £2.75 from a local hardware shop.
It says on the packet to put the wheel on in the direction of the
arrows. Yes ok. Now the arrows indicating direction of spin are on one
side with some writing. ie size of wheel etc. So that means writing side
up as it is placed on the spigot of the grinder.

Would there be any harm done if the wheel was placed the other way
round? I noticed it seemed to cut better this way, or was it my
imagination? Also I noticed that the blades were going a reddy blue in
colour....burning I guess. Is that a sign of poor quality or too much
pressure or?
BTW, I am using it to cut concrete 50mm paving flags.

Thanks

On Thu, 25 Nov 2004 16:49:37 +0000, Bob H
strung together this:

I have a Pro Tec 115mm diamond cutting wheel; bought it a couple of days
ago for £2.75 from a local hardware shop.

1. If it's a cheap diamond blade don't expect miracles.
2. It's probably a bit undersized for more than one or two cuts in
concrete slabs.
3. If it says it spins one way, then that is the way it spins. Safety
related generally.
4. The funny colour indicates that you have got a cheap, undersized
diamond blade, used improperly for the job in hand, and probably in a
bit of an over zealous fashion.
--

SJW
A.C.S. Ltd
Please reply to group or use 'usenet' in email subject

Lurch wrote:
On Thu, 25 Nov 2004 16:49:37 +0000, Bob H
strung together this:


I have a Pro Tec 115mm diamond cutting wheel; bought it a couple of days
ago for £2.75 from a local hardware shop.


1. If it's a cheap diamond blade don't expect miracles.
2. It's probably a bit undersized for more than one or two cuts in
concrete slabs.
3. If it says it spins one way, then that is the way it spins. Safety
related generally.
4. The funny colour indicates that you have got a cheap, undersized
diamond blade, used improperly for the job in hand, and probably in a
bit of an over zealous fashion.

Ok thanks.
Now then, on point 1. Yes I agree
On Point 2. Yes it probably is, but I knew that before I bought it and
it does what I want, sizewise that is.
On point 3. Yes I agree there as well
On point 4. Well, like I said in my original post, it looks like it was
burning/getting toooo hot.
I have used 4" grinders/cutters on steel extensively over the years when
I was in engineering, and therefore I know what burning/too hot metal
looks like. It seems like it does not like the pressure that the
ordainary run of the mill £1.30 somethins do.

Oh well, lesson learnt. I'll buy a dearer one next time.

Thanks for confirmation on what I thought.

On Thu, 25 Nov 2004 18:07:48 +0000, Bob H
strung together this:

Oh well, lesson learnt. I'll buy a dearer one next time.

I've had a Makita 115mm diamond blade for £14ish. They went through
miles of that really hard stone that I can't think of the name of
stone for chases and never overheated etc...
--

SJW
A.C.S. Ltd
Please reply to group or use 'usenet' in email subject

On Thu, 25 Nov 2004 16:49:37 +0000, Bob H
wrote:

BTW, I am using it to cut concrete 50mm paving flags.

Then use a 9", not a 4 1/2". That sort of cut is hard on a tiny disk,
no matter who made it.
--
Smert' spamionam

Lurch wrote:
On Thu, 25 Nov 2004 18:07:48 +0000, Bob H
strung together this:


Oh well, lesson learnt. I'll buy a dearer one next time.


I've had a Makita 115mm diamond blade for £14ish. They went through
miles of that really hard stone that I can't think of the name of
stone for chases and never overheated etc...

I went down to B&Q this morning for something, and while I was there I
found they had some 115mm diamond cutting wheeels in now. Can't think
whos make they are, but they were £9.98 each.

Andy Dingley wrote:
On Thu, 25 Nov 2004 16:49:37 +0000, Bob H
wrote:


BTW, I am using it to cut concrete 50mm paving flags.


Then use a 9", not a 4 1/2". That sort of cut is hard on a tiny disk,
no matter who made it.

Yes I take your point, but it was/is a question of cost for what I was
doing. I had to cut only 5/6 flags out of 18, and I made a cut about
10mm deep on both sides then broke it through.
Now I am not very likely to use a 9" grinder/cutter for anything else,
given that I bought the 4 1/2" one for only £24. It probably would have
cost me that much to hire a 9" one.

Thanks anyway

On Fri, 26 Nov 2004 11:40:31 +0000, Bob H
wrote:

Yes I take your point, but it was/is a question of cost for what I was
doing.

Given the high cost of stone, diamond blades and the really cheap 9"
machine from Screwfix (Kenzo ?), I'd be inclined to try and keep the
dust out of my bearings.
--
Smert' spamionam

Andy Dingley wrote:
On Fri, 26 Nov 2004 11:40:31 +0000, Bob H
wrote:


Yes I take your point, but it was/is a question of cost for what I was
doing.


Given the high cost of stone, diamond blades and the really cheap 9"
machine from Screwfix (Kenzo ?), I'd be inclined to try and keep the
dust out of my bearings.

Is that a feature of that 9" machine...keeping the dust out?

Yes I found a wide variation of 115mm diamond cutting blade prices, from
£2.75 to about £21 something. A point I noticed on the ones from B&Q
which I looked at this morning, it said that a cut of only 12.5mm deep
should be made, so hence me doing both sides. But that was not just on
the 115mm ones, it also included 'upto 230mm'

On Fri, 26 Nov 2004 14:35:32 +0000, Bob H
wrote:

Is that a feature of that 9" machine...keeping the dust out?

A disposable 9" keeps the 4 1/2" running. With enough dust I can
probably kill the bearings in the 9" at just about the same time as
the design life of its gearbox.
--
Smert' spamionam

Andy Dingley wrote:
On Fri, 26 Nov 2004 14:35:32 +0000, Bob H
wrote:


Is that a feature of that 9" machine...keeping the dust out?


A disposable 9" keeps the 4 1/2" running. With enough dust I can
probably kill the bearings in the 9" at just about the same time as
the design life of its gearbox.

Not sure what you mean here 'A disposable 9" keeps the 4 1/2" running.'
A disposable 9" what? Grinder, wheel?? how does it keep the 4 1/2" running?

Bob H wrote:


Not sure what you mean here 'A disposable 9" keeps the 4 1/2" running.'
A disposable 9" what? Grinder, wheel?? how does it keep the 4 1/2" running?

Translation: Andy has a good quality 4 1/2" grinder, which he loves
fettling with. He chooses not to use it for cutting slabs, since (a)
it's the "wrong" tool for the job (cutting depth is limited), (b) he
doesn't want the masonry dust najjering the bearings in his decent grinder.

So he expresses a preference for buying a cheapie 9" grinder (these daya
available at about the same price as a day's hire of a decent-brand but
possibly rather worn one) and keeping it for slab cutting and similar
rough jobs.

I'm kinda with him on this one, but would add welding gauntlets, thick
trousers, decent workboots, and (most of all) standing to one side of
the work as sensible setup for using the 9".

Stefek

Stefek Zaba wrote:
Bob H wrote:


Not sure what you mean here 'A disposable 9" keeps the 4 1/2" running.'
A disposable 9" what? Grinder, wheel?? how does it keep the 4 1/2"
running?

Translation: Andy has a good quality 4 1/2" grinder, which he loves
fettling with. He chooses not to use it for cutting slabs, since (a)
it's the "wrong" tool for the job (cutting depth is limited), (b) he
doesn't want the masonry dust najjering the bearings in his decent grinder.

So he expresses a preference for buying a cheapie 9" grinder (these daya
available at about the same price as a day's hire of a decent-brand but
possibly rather worn one) and keeping it for slab cutting and similar
rough jobs.

I'm kinda with him on this one, but would add welding gauntlets, thick
trousers, decent workboots, and (most of all) standing to one side of
the work as sensible setup for using the 9".

Stefek

Ok right, gotcha now!
Have you read one of my earlier posts in this thread in which I said
what I read on the packet of a 115mm disc. Only 12.5mm deep cut for
115mm wheels and upto 230mm which is 9". So according to that it makes
no difference in theory, but in practice with ordinary cutting wheels
you can cut as deep as the wheel will allow.

Stefek Zaba wrote:

Bob H wrote:


Not sure what you mean here 'A disposable 9" keeps the 4 1/2" running.'
A disposable 9" what? Grinder, wheel?? how does it keep the 4 1/2"
running?

Translation: Andy has a good quality 4 1/2" grinder, which he loves
fettling with. He chooses not to use it for cutting slabs, since (a)
it's the "wrong" tool for the job (cutting depth is limited), (b) he
doesn't want the masonry dust najjering the bearings in his decent grinder.

So he expresses a preference for buying a cheapie 9" grinder (these daya
available at about the same price as a day's hire of a decent-brand but
possibly rather worn one) and keeping it for slab cutting and similar
rough jobs.


You mean you can buy a 9" grinder and dimond disk for 18 quid?

(What I paid for a days hire of a massive one)

Tell me where?


I'm kinda with him on this one, but would add welding gauntlets, thick
trousers, decent workboots, and (most of all) standing to one side of
the work as sensible setup for using the 9".


********. I just picked it up and cut.

Got a few pits of hot sand on me arms. not as badas a missie bite.

I werar glasses tho.


Stefek