Hello, I didn't want to hijack papadan's post, so I am here with some odd size blades. Porter Cable seemed to be the king of odd sized saws & blades!! 4-1/2, 6-1/4, 6-3/4, 7, 7-1/2, 8, 8-1/4, and a 10-1/4. I believe I also have a 6-3/4" saw here somewhere. The 6-1/2 in the photo is a Roc-Edge, the other 2 are Porter Cable. Regards, Lou

Yep, lots of sizes. I just ordered an 8 1/4" from Amazon. I have a compound miter saw, Delta, that I bought in the late 80s when remodeling our home. Had lots of trim work to do and only a cheap wooden miter box, so I bought the Delta at Lowes. I've got a PC left blade 7 1/2", HF 10" sliding miter, Ryobi 10" table saw, Ridgid 10" table saw. Picked up a brand new Craftsman 6 1/2" at a flea market for $1 for the old saw I'm restoring. Found a stack of 4 and 4 1/2" blades in an auction box and gave them to my neighbor for a drywall saw he has. Now days I don't do much work and usually just grab a hand saw for a quick cut. ;-)

My first tablesaw was a Delta 9"

The blades started to get less common about 10 years ago.

Chilly

Delta Sawbuck - 8 1/4

Not quite blades, but close.  Many years ago I bought was a 1953 Craftsman with a 4" jointer mounted on the stand at an auction.  It was on the cover of the 53 power tool catalog that came with it.   I loved the setup!  The arbor is 1/2" so I had to add bushings to use 5/8" x 8" blades. I never did find 8" x 1/2" arbor  blades.  When disposable carbide blades came on the scene, 8"ers didn't follow.   They are now expensive & never on sale. Sharpening is more than orig cost of blades.  I now use a 10" Craftsman on the single post stand that my Grandfather bought new in the early 50's. 

6 1/2 and 8 1/4 are old standard sized  Skilsaw blades.