ROT (for uk.tech.digital-tv) - Circular Saws, Blade Sizes

[Java Jive]

I've just decided that I need a circular saw to help me complete the mountain of DIY tasks that I've recently and unexpectedly come to face, so, having a gratuity post-c*ck-up voucher at B&Q for £50 I started looking there. Naturally I read the reviews of the saws that looked promising, one of which was this ...

... about which someone wrote (referring to the bore size of the blade, that is the diameter of the central mounting hole) ...

"16mm saw blades for this are not available. only 20mm blades available and expect to be used with an adaptor but no suggestion of where to buy the adaptor. no one at b&q knows anything about this. all you can do is ring McAllister directly."

... and one or two others have commented similarly.

Thinking that it would be a good idea to check on what blades are available before choosing a saw, I started to scout around the websites of B&Q, ScrewFix, & ToolStation, but rapidly got bogged down in bewilderment. How many sizes of blades would you think were needed to cover the range, say, 75 - 350mm on a rational basis? Perhaps one every

25mm, giving 16 different blades in all? Disregarding blade thickness, there are 37 different sizes available over approximately this range! Furthermore, many blades having the same outer diameter have different bores! By now thinking that I needed to buy a saw where blades for it are most likely to remain available, I counted the number of items of each size over all three sites, and for the benefit of others I append the table below.

Basically if you want a small to medium size saw for home DIY, etc, my advice would be to choose one having one of the following sizes of blade:

Most Popular Circular Saw Blades (dimensions in mm) Dia Bore Numbers of spare blade items available

190 30 22 165 20 21 216 30 14 250 30 13 160 20 12 210 30 10

Full Table

Circular Saw Blades (dimensions in mm) Dia Bore Numbers of spare blade items available

65 15 2 76 10 4 85 10 2 85 15 3 86 15 1 135 12.5 1 136 20 2 140 20 1 150 10 2 150 20 3 160 20 12 160 30 5 165 20 21 165 30 5 180 30 4 184 16 1 184 30 8 185 20 2 190 16 1 190 20 3 190 30 22 200 30 2 205 30 1 210 25.4 2 210 30 10 216 30 14 230 30 5 235 30 5 250 30 13 254 30 4 255 25.4 2 260 30 4 280 30 1 300 30 1 305 30 7 315 30 1 355 25.4 1

BTW, if you're thinking 25.4, 254??? There are 25.4 mm to the inch, so these figures are 1" and 10" respectively.

[alan_m]

Some blades come with adapters

(20mm to 16mm reduction ring included)

For larger blades with a 30mm bore Saxton include 16, 20, 25 and 25.4mm reduction rings with their blades.

[alan_m]

Plenty of Ebay listings for bore reducing rings.

[Java Jive]

Thanks for the information, which may be useful to others like the original reviewer I quoted, but for myself I think it's more sensible simply to purchase a model for which spares are easily available. I've decided on 165 x 20 as having several models of saw which are well reviewed and themselves easily and cheaply available, even up here in the wilds of Scotland!

[Brian Gaff]

I'm sure somebody I know has told me in the dim past that adaptors for common ID diameters often come with the saw. However I can also see that if true, then they can also easily vanish into that mysterious place which eats tools and handy little adaptors. Brian

[Bob Eager]

I bought a Bosch TCT blade recently. The saw uses the 165mm blades, so it has a 16mm shaft. It didn't come with an adaptor (the blade that came with it had a 16mm hole) but the new blade did.

[Rob Morley]

Did anyone think that? Anyone at all?