Circular Saw Ignorance

[Tdog]

My wife has been asking for a gazebo at the side of our house. If I do it, I would like to go with a hexagon or octagon design - - and use a metal roof. That would mean cutting the metal roofing to fit. Are there blades that will fit a circular saw for this purpose? If not, is there any way to cut the roof panels any way other than by hand?

 

[WVBill]

As a matter of fact, when I built my pole barn a couple of years ago, we put a metal roof on it. I got standard sized panels and had to cut about 1 foot off the end of each one.

I got a metal cutting blade for my circular saw and it worked OK. The thing only had like four teeth. We had to go REAL slow and boy did it make NOISE!!!

I was thinking the whole time that I should have gotten an air-tool tin snip like I've seen used for auto body work - although I don't know how that would have handled the ridges in the metal roofing.

 

[Bird]

I've used a metal cutting abrasive type blade myself to cut sheet metal with a circle saw (used to keep two circle saws; one with the abrasive blade for metal and one with a metal blade for wood), but my brothers tell me to just use the regular old wood cutting blade, but turn it around backwards. They say it works fine if you can stand the noise it makes.

 

[jwstewar]

I had to cut several pieces of sheet metal down to 8' lengths a couple of years ago. Purchased a metal cutting blade for my DeWalt 18volt cordless circular saw. Worked like a charm and didn't have to worry about the cord getting caught in the metal and me lighting up like a Christmas Tree. But like Bird said, it is loud. Didn't realize it would be that loud and was in a hurry and didn't feel like digging the hearing protection out, sure do wish I would've. Ears were ringing for 2 days.

 

[EdKing]

For metal roofing, we just used a decent carbide tipped blade. Worked fine and no changing the blade to cut extra slats for the roof.

 

[RobS]

I've run the blade backwards to cut vinyl siding in both circular saw and power mitre saw. Works like a champ. I think if I were to cut metal I'd look for an abrasive cut-off blade. Seems like it might be a bit safer /w3tcompact/icons/smile.gif

 

[beenthere]

Bird
Your brothers are right. And add the hearing protection. No need for buying an additional blade.

 

[BB_TX]

As mentioned, there are abrasive cut off blades (basically a thin grinding wheel). There are also metal blades designed specifically for cutting sheet metal. Rather than teeth as such, they have small slots cut in the outer edge all around. Worked well when I put up my metal building. And as also mentioned, I have heard turning a standard blade backwards works well. By all means use ear protection. And eye protection too as it will throw metal slivers.

 

[hazmat]

What kind of metal? You can cut aluminum w a wood blade going forward. As mentioned wear hearing protection as well as a face shield & eye protection, it sprays a bunch of chips.

The best way is the aforementioned air nibbler. Harbor frieght has a couple for lesss than $50 <A target="_blank" HREF=http://www.harborfreight.com/cpi/ctaf/Category.taf?CategoryID=331>Harborfreight metal cutting air tools</A>

 

[mikim]

Re: turning a blade backwards to cut metal -- I found a cheap plywood blade works best - has more & smaller teeth - seemed to cut smoother - and using a wood blade turned backwards will ruin it for anything else - so the cheaper the better

 

[Egon]

Thats what I use Mike but I keep an old blade on hand just for this purpose.

Egon

 

[gmason]

Tdog, I've got one of the Dewalt metal cutting chop saws that uses a carbide balde vs and abrasive wheel. The 14" saw blade had 70 teeth and they don't appear to be anything special. So, for sheet metal, I would try to get a 25-30 teeth carbide blade for the circular saw and try it. Yea the teeth will dull quicker, but on blade shoould be enough to rip all that you would need.
My saw doesn't hardly throw sparkes either.

gary

 

[Tdog]

Thanks guys.

I thought I'd get knowledgeabel replies here.

I'll definitely use the ear & eye protection. Think I'll try 1st using a blade backwards.

 

[gerard]

refer to hazmat's post. I've used the air nibblers and they work great on sheet metal. The power shears would also work well but I think they cost a little more. With the nibblers you can clamp a peice of angle iron to the sheet metal as a guide and get a perfectly straight cut. Circular saws are a little rougher to get an exact cut.

 

[Bird]

I've never "used" nibblers and power shears on a job, but I repaired a few pneumatic ones, then "test drove" them before sending them back to their owners/w3tcompact/icons/wink.gif; pretty neat tools.

 

[Gary_in_Indiana]

My local woodworking store recommended either a rather expensive metal blade or a plywood blade reversed. They did say that a carbide plywood blade was my best non-metal blade choice if I had a lot to do. Otherwise a regular plywood blade reversed ought to work fine for me. Good luck with your gazebo. /forums/images/graemlins/smile.gif