using old circular blade

[JWBH]

I see on the 'screw fix' website that there cheap mitre saw circular blade is 190 mm with 16 mm bore. So as a novice i am guessing this must be the current standard size?

not long ago i bought a Ryobi mitre saw EMS-1425L. The other day a friend said he has an old circular saw blade that was a high quality one and has been resharpened, which he has just given me. The size of this one is 235mm with 15mm bore (by my meaurements).

Is the bore size universally the same? Am i likely to be able to use this old blade on the Ryobi? (bearing in mind the outside diameter is a bit different and the bore looks to be 1mm different. thanks for advice.

[Paul D]

235mm to 190mm is more than a bit different. The 235mm (9 1/4") simply won't fit inside the guard of a saw designed for a 190mm (7 1/4") blade unless by chance you currently happen to have at least 25/30mm clearence above 190mm blade. If you do have that much clearence it is obviously a 235mm (9 1/4") saw and blade will fit.

15mm is an odd sized bore. Imperial bore of 5/8" (15.875mm) 16mm is the metric common size

[Andy Dingley]

16mm is fairly standard for small (hand-held and pull-over) saws. These saws are less standard than cabinet saws though. You will also see 20mm on cheapies, which is common on saws, difficult to find blades for and best avoided for that reason.

The old standard for big cabinet saws was 5/8" or 15mm. People do fit

16mm blades to these, but they run badly with lots of vibration, the cuts are bad and it's an unsafe practice you really shouldn't do. It's now getting harder to find decent 5/8" sawblades in the UK. The modern standard is 30mm. Fortunately a 5/8" - 30mm adapter is easy and cheap to get (Axminster) and that's a safe and acceptable way to work.

[Paul D]

A quick note on using bushes for the anwary. Make sure that the bush is same thickness or thinner than the blade. I have seen many inexperienced people caught out by this.Even a cpl of thou difference and the flanges will not clamp properly. I have started machining my own bushes as I am finding that the accuracy of bushes (both bore and OD) is getting very slack nowadays. Guess thats what happens when they start pressing them out in th millions in China.