Using a smaller blade on a circular saw

[davidmiller]

Hello. The current blade is 185x20 24 teeth. I can't get anything and need it for Monday.
It's it ok to use for example a 160x20 blade. I assume the inner dimension being the same wil is the important one but is there a risk that I've overlooked?
Cheers

 

[Diver Fred]

The space between Riving Knife, if fitted, and blade will be greater so possible to get something trapped.
Depth gauge will be inaccurate.

The bit I'd be most concerned about is the blade thickness - not the tips, the actual blade - is it the same to ensure it doesn't slip.

 

[Deleted member 174758]

It may be possible if you are on Amazon. These are both possibles and showing delivery for tomorrow to me (and as I live in the back of beyond...):

Saxton 2-blade set 185 x 30mm (24t and 40t) c/w reducers

Toolzone 3-blade set

There are others. For example Toolstation have a

Set of three Toolpak blades 184 x 30mm with reduction bushes

My local (to work) branch has 17 in stock for collection

184/185mm are about he same but a 190mm blade will probably be too big (so, size is important!). Of the three there the Saxton blades are better, but if you are just doing rough work I doubt it matters much what you have on the saw.

 

[big-all]

other comments
cutting depth reduced by 1/2" 12mm
and iff a riving knife is fitted will almost certainly catch on the edge off the work

 

[davidmiller]

Thanks for your answers everyone.
What I'm taking from you all is to get the right size or very close.
I didn't know about reduction bushes. I like the idea of them perhaps with the tooolstation blades. Not sure if the they need to be the same make as the blade though?
Only problem is I'm not sure how thick the old blade is. If the new one has to be the same I suppose I could use adjustable spanners as micrometer to check

 

[Deleted member 174758]

They don't need to be the same make (a hole in a blade is just a round hole at the end of the day). The bushes should ideally be the same thickness or slightly thinner than the blade (but they almost always are) - this is so the clamping washer on the saw will work properly. Blades if 180 to 190mm are often around the 1.8 to 2.3mm body thickness with a kerf (the width of groove formed by the carbide teeth) of 2.2 to 2.6mm. The main thing to ensure is that the riving knife is slightly thinner (0.2mm or more) than the kerf