Benefits of using a smaller saw blade on a table saw?

[sploo]

...and the blade should be raised so that the entire tooth is exposed...but no more.

Cheers, I've often wondered how much of the blade should be exposed. I thought people only had a little bit of the blade peeping out for safety reasons but it actually cuts better that way?

I've always understood that you'd get a better quality of cut by having the most number of teeth in the cut as possible (i.e. blade low) - though you still want the gullets exposed in order to clear sawdust.

I certainly see the safety argument that having the blade high for even thin stock means the tooth pressure will be pushing the stock down onto the table (rather than towards you) but without a zero clearance insert (ZCI) I'd expect to see more tear out on the bottom face. Just my $0.02 though...

 

[OscarG]

HSE advice not to go below 60% of the design diameter personally I do not go below 80%

I have a DeWalt table saw with a 250mm blade as standard. I just asked DeWalt if it was safe to use a 6" diameter ultra fine kerf guitar fret slotting blade and was told "we don't recommend using anything other than a 250mm blade."

Do you think they're playing it ultra safe? Does it sound dodgy trying to use a 6" blade in there?!

 

[deema]

Have a look at the following link

http://www.swedex.co.uk/uploads/CATALOG ... 874d4b.pdf

The Swedex catalogue provides loads of extremely good information on circular saw blades, peripheral seeds, cutting quality just about everything your likely to want to know. For each blade they provide the recommended speed range so you determine if their 6” blade will work with your Saw. The spindle speed will be provided somewhere on the Saw.

I really like Swedex blades, I also like Atkinson Walker blades and they are made in the U.K.

 

[OscarG]

Thank you, I'll check that out.

 

[RickG]

I'm a total newbie to this, but it makes sense to me that Swedex are saying to use the smallest blade possible that will do the work.

The benefits of using a small blade would be the teeth blade of the blade will be travelling faster. This is because t tooth 100mm from the centre has less far to travel to make a complete revolution than a tooth 150mm from the centre.

Smaller blades will be less likely to jam. This is because the torque of a small blade will be greater. An obstruction applying a restriction will have greater leverage on a tooth 150mm out than if that tooth were only 100mm out.

 

[PAC1]

I'm a total newbie to this, but it makes sense to me that Swedex are saying to use the smallest blade possible that will do the work.

The benefits of using a small blade would be the teeth blade of the blade will be travelling faster. This is because t tooth 100mm from the centre has less far to travel to make a complete revolution than a tooth 150mm from the centre.

Smaller blades will be less likely to jam. This is because the torque of a small blade will be greater. An obstruction applying a restriction will have greater leverage on a tooth 150mm out than if that tooth were only 100mm out.

No. You need to think about the circumference of the blade. A 300mm diameter blade has a circumference of 942mm whilst a 200mm diameter saw has a circumference of 628mm. So if the spindle is turning 3000rpm the 300mm blade travels 2826m or 169 KM per hour and the 200mm blade travels 1884m or 113KM per hour.

 

[RickG]

Ok. So a smaller blade travels a shorter distance, causing less friction, less heat. All good.

So why do saw makers have concerns over the use of very small blades on their saws?

 

[Noel]

Personally I like the blade somewhere nearer full height than just above the work piece.
Best way to find out what suits you is try all options and find a happy medium between safety (perception of risk) and quality of cut. If you're not happy with the blade an inch or two above wind it down until you are happy. The best height is the height you are happy with.