I have a "system" for using a 7-1/4 blade to its' fullest. Most of my carpentry work was when I had recieved a
severe shock doing electrical work and needed to settle my brain and re-coordinate my body parts. The fellow I worked for (with?) did a lot of decks from pressure treated wood. I would buy a "contractor 6 pack" of cheap carbide blades, using them for "new" work. They didn't last very long, they were cheap blades. After a couple of teeth had been knocked off, I would put the blade on a different saw. One with bad blade bearings, so the blade wobbled and cut a crazy kerf. But Hey, it was "junk" work and demolition. If I hit a nail, it was already a junk blade. No loss. . .
edit: BTW I totally blew a brand new blade one time when I put it on backwards... DON'T ASK... what an idiot I was.. I knew I had to mount it the right way, and I still managed to screw it up.
The key usage here:
When the blade was beyond using as a wood blade, I would mount it
backward on a third "beater" saw and use to cut sheet metal siding and roofing. FWIW,
using a blade that way is dangerous, noisy, generates shrapnel, and leaves a ragged edge. Very disareeable. But it works and on a job site will save significant time. It is not usable beyond about 16 or 18 gauge, but I had a source for "seconds" of 20 gauge commercial siding at a good price. The rig did work there, fast and well. Far faster than using a shear or snips.
Of course, a blade abused in such a manner doesn't last very long. When it was reduced to just a wavy ripple of an edge, I would, using a torch, cut it down to a four winged edger blade. Wife had an old edger that I made a 5/8 adaptor for. Running it against a concrete sidewalk does its' thing and the blade is soon worn out. But it made a couple of passes where it counted.
Once the saw/edger blade was reduced to a small circle, I would hang it on a nail as a 5/8 "fender" washer. I did use them on my tractor, 5/8 is a common size there and the oversize washer makes fitting it easier. That sort of work is long past, but there are still a few out in the barn in some deep, dark hiding place. If I again need one, I have it.
So, how's that for "recycling"?
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