Also crossposted to rec.woodworking

Installing Hardie Plank siding. (Fiber cement combination) Manufacture
states that I should use a special blade. Went to Home Depot, and yes, they
make a special blade. It is simply a carbide tooth blade with with a total
of 6 teeth. 7-1/4 inch diameter.

Can somebody explaing why a six tooth carbide blade would cut any better
than, say, a 24 or 40 tooth blade that I use for lumber? I don't understand
the physics.

Thanks,

Ivan Vegvary

"Ivan Vegvary" wrote in message
news:lFsBi.1413$9T5.789@trndny02...
Also crossposted to rec.woodworking

Installing Hardie Plank siding. (Fiber cement combination) Manufacture
states that I should use a special blade. Went to Home Depot, and yes,
they make a special blade. It is simply a carbide tooth blade with with a
total of 6 teeth. 7-1/4 inch diameter.

Can somebody explaing why a six tooth carbide blade would cut any better
than, say, a 24 or 40 tooth blade that I use for lumber? I don't
understand the physics.

Thanks,

Ivan Vegvary

The 6 tooth will have a more controlled feed cut and run much cooler. I
don't know what grade the carbide is or tooth style or kerf set. There are
a lot of variable in play and you shouldn't have to do the homework over
again. Use the recommended blade.

On Aug 29, 10:34 pm, "Ivan Vegvary" wrote:
Also crossposted to rec.woodworking

Installing Hardie Plank siding. (Fiber cement combination) Manufacture
states that I should use a special blade. Went to Home Depot, and yes, they
make a special blade. It is simply a carbide tooth blade with with a total
of 6 teeth. 7-1/4 inch diameter.

Can somebody explaing why a six tooth carbide blade would cut any better
than, say, a 24 or 40 tooth blade that I use for lumber? I don't understand
the physics.

Thanks,

Ivan Vegvary

While the 6 (or 4 on the blades I have seen) tooth design does help
control the chip load, I think it has at least as much if not more, to
do with economics than physics. The teeth on the blades made for fiber
cement board while mostly carbide, are poly crystal diamond (PCD)
faced. You may have noticed that that 6 tooth blade cost more than
your 40 tooth wood cutting blade? would you really want to pay 4 times
more for 24 teeth?
I have cut a limited amount of fiber cement with a wood cutting blade
and it worked well enough, but forget about using the blade again for
wood. I have also used a diamond wet saw, which, while messy and not
spectacularly fast, did give a very smooth cut.

You don't want the abrasive dust rubbing in the cut. The wider
gullets on the 6 tooth blade clear the dust easier. The more teeth
the more heat you would generate. Yes the special blade is thinner
than a standard blade. The carbide tips are probably a special mix to
withstand the shock and the heat. They hold up pretty well. The
question is, the 6 tooth blades work so well cutting the cement board,
why would you use something else?

On Aug 30, 1:34 am, "Ivan Vegvary" wrote:
Also crossposted to rec.woodworking

Installing Hardie Plank siding. (Fiber cement combination) Manufacture
states that I should use a special blade. Went to Home Depot, and yes, they
make a special blade. It is simply a carbide tooth blade with with a total
of 6 teeth. 7-1/4 inch diameter.

Can somebody explaing why a six tooth carbide blade would cut any better
than, say, a 24 or 40 tooth blade that I use for lumber? I don't understand
the physics.

Thanks,

Ivan Vegvary

Those six carbide teeth are faced with polycrystaline diamond