I picked up an Evolution mitre saw and found they use their own blade bore of 25.4mm diameter. All the descent blades seem to use 30mm, as the blade carrier is removable from the saw I thought I would make another as I don't like the adapter rings blades come with. My first chunk of metal turned out to be case hardened, and not just a little, it also had a keyway in it that I didn't account for properly so was going to be undersized. This looked like another project about to get shoved on the creaking back burner. However this dinner time a friend showed up with a handful of scrap metal pins and the heads just happened to be about the right size I needed.
Most of the head was sawn off and then put in the lathe ready for machining. I had a bit to remove off the diameter (6mm) off the pin, and I wanted to do this all without removing the pin from the chuck. Machining was done, and I bored to size the adapter before parting it off. Now in all this excitement I clean forgot, is this a 30mm adapter, do you feel lucky punk !!!
At that point I knew I wasn't Clint, and had managed to get 29.9mm as my finished diameter.

So I flicked my spurs and visited Bodge City.... A nice ring of punch marks got the blade snug and centred, this blade just happens to have 30mm bore but isn't the correct size for the saw.
My adapter at the side of the one supplied with the saw, other than the slight error it fits the saw just as well as the commercial one. This final image also shows one of the pins I machined it from.
I just got complacent from machining soft materials and got bitten by backlash. Still a bit of different machining and a component made, you can't buy.