On Thu, 07 Jun 2007 10:11:55 +0100, Autolycus wrote:


"Tim Downie" wrote in message
...
I've hired a saw for cutting concrete monoblock for my driveway. The
hire shop recommended using the water spray system for dust supression
which works a treat.

However, the instructions with the saw say this should only be used
with diamond tipped blades, not abrasive disk type blades which I'm
using.

Is there a problem? It still cuts but I'm finding it hard work and I
wonder whether the water might be providing too much lubrication

I found diamond blades made a superb job of cutting concrete blocks,
using a cheapo 14" chop saw - so no water spray. The dustfullness was
terrific. Mine is similar to:

http://www.machinemart.co.uk/shop/pr...ve-cut-off-saw

and I made a couple of simple wooden jigs to hold blocks for 45 degree
cuts.

If you do contemplate hiring a diamond blade, watch out for wear
charges. Some places charge a small fortune per millimetre of wear, and
it's difficult to argue whether your blade has worn by 2mm or 3mm.
Diamond blades have dropped in price so it's probably worth buying your
own - but, I admit I prefer buying to hiring in general. I've found the
chop saw, with a metal-cutting abrasive disc, invaluable for all sorts
of jobs since the killer app block paving job ended.

Tim,
Diamond is the only way to go. Let the blade work, that is
don't force it. Sparks coming off it means you are forcing
it and wasting matrix.

Kevin,
I once hired a saw and blade late one friday afternoon. The guy had to put his beer down to use the vernier to measure the diamond. On monday morning after using the machine most of the weekend the blade was bigger than it started out.
Good stuff this Aussie beer,

Regards
Bill

--
Bill
http://www.builderbill-diy-help.com/