Cutting roof sheet with wire - GIF

[Frank S]

I ended up buying a guillotine type sheer with the dies/blades of the profile of metal that I used....but that had its own issues.

Did yours have a good clamp down for the sheet? I bought one that didn't have a good clamp. After I made a full profile clamp for it and converted it to hydraulic instead of manual it became a pleasure to cut dozens of sheets per day. We had it mounted on the rear of a trailer.

[nova_robotics]

I've used circular saws with the blade on backwards.

Can you elaborate on that? This trick is new to me but it sounds super interesting. I'm guessing you were not using carbide tipped blades?

[hemmjo]

Cutting sheet goods with a circular saw requires negative rake on the tooth. You can buy specific blades designed for steel. Putting a regular blade on backward gives you that negative rake. A regular blade on backward works almost as good as the special metal cutting carbide blade for 1/4 to 1/3 the cost.

I save my dull/damaged carbide blades for things like this.

[nova_robotics]

Cutting sheet goods with a circular saw requires negative rake on the tooth. You can buy specific blades designed for steel. Putting a regular blade on backward gives you that negative rake. A regular blade on backward works almost as good as the special metal cutting carbide blade for 1/4 to 1/3 the cost.

I save my dull/damaged carbide blades for things like this.

I figured for sure if you ran a carbide tipped blade backwards it would just shatter the carbides or rip them off of the brazing. With most carbide cutters if you keep them in compression they'll last ages, but the second they go into tension they just bust to pieces. Well that's just super interesting. I may try that some day. Thank you.

[ductape]

I figured for sure if you ran a carbide tipped blade backwards it would just shatter the carbides or rip them off of the brazing. With most carbide cutters if you keep them in compression they'll last ages, but the second they go into tension they just bust to pieces. Well that's just super interesting. I may try that some day. Thank you.

As hemmjo said above, it works pretty well with carbide-tipped blades that are damaged and no longer useful for normal cutting. There isn't much of an issue with teeth shattering or breaking loose, but it does happen occasionally. A reversed blade cutting through the bottom of the sheet kind of deflects the debris. Wear your safety sandals and put all your thumbs up. It's also loud as all heck, but fast.

[Frank S]

Can you elaborate on that? This trick is new to me but it sounds super interesting. I'm guessing you were not using carbide tipped blades?

No not carbide tipped. A regular blade preferably one you would rather throw away than think about sharpening Just install it backwards and go for it.
I've used chainsaws as demolition saws by flipping the chain and bar upside down to cut a door into the side of a building.