I have no clue on the "nibbler vs shear" but I would use a metal cutting blade in a typical saw that you probably already have.

http://www.toolbarn.com/milwaukee-48-40-4015.html

I have a metal cutting saw (8") and it works great, but I would bet that any circular saw with one of these blades would do well for you.

That nibbler ought to do a decent job for you on the smaller, more intricate cuts. For longer straight cuts, shears would be a better option.

Putting siding on a factory this summer, we found that neither was better than an aluminum oxide abrasive blade mounted on a Skil saw. The ridges made a cross cut impractical with anything else, while long rips went faster than either cutting tool would.

I'd use a plasma cutter myself.

Knibbler
Uses a die that runs up and down punching holes thus removing metal. No limit to the direction you can travel. If you were running a straight line and wanted to turn left, you would be able to do so without backing up or removing the tool from the work surface. You may have a hard time finding replacement parts for the die. You can run straight lines but not free hand. Would need to use a straight edge.

Shears
Acts like scissors. Great for straight cuts and also has a degree of flexibility in the turn. Probably be able to run a 10" hole not sure if you could get down to a 6". Knibbler excells at the radius. Hard to find replacement parts or takes more time than your willing to wait for replacement cutters. If you are after straight cuts shear would do well. No need for a straight edge just a layout line. Works best on flat sheet stock. Not sure of you have experimented with a jig saw and a good (Bosh) metal blade? I use the extra long blades. Need to have metal well supported on both sides of the cutting area and within about 1/4" of kerf. There is also the option of a metal blade for the circular saw. However, be warned about flying metal dust. Get that stuff on new wood and you got one hell of a mess on your hands. Metal dust plus humidity equals rust ! The painters and carpenters will love ya for that!

I was always under the impression that electric shears are for thinner gauge metal and the nibblers are for the thicker stuff. I noticed that a lot of the electric shears I have seen are good for 18 gauge or so.

I did a steel garage last year. I bought the dewalt 18ga electric shears to cut the steel siding panels, best investment I ever made! Seems like you made the right choice with the nibbler.

Dave

plazaman said:

Guys, can you tell me what the difference between a nibbler and shears are (Electric units)

Click to expand...

Nibblers are great for cutting out curves and twisty angles. I've only cut light gauge stuff with nibblers though never 12.

Tin, I use to just put my wood blade in the circular saw backwards for cutting thin steel, worked just dandy in a pinch.

Yes, I've done that with a junk blade--or created a junk blade that way. :laughing:

Agreed, it works okay for a little bit of cutting. But for real quantities like we had on that job, and what i think Plazaman is doing, you need something better.

I admit I've never tried a steel/carbide made-for-that blade, so i don't know how that would compare.

Inner10 said:

Tin, I use to just put my wood blade in the circular saw backwards for cutting thin steel, worked just dandy in a pinch.

Click to expand...

Good point on the gauge. Shears and Knibbs will only cut so thick.

dkillianjr said:

I was always under the impression that electric shears are for thinner gauge metal and the nibblers are for the thicker stuff. I noticed that a lot of the electric shears I have seen are good for 18 gauge or so.

I did a steel garage last year. I bought the dewalt 18ga electric shears to cut the steel siding panels, best investment I ever made! Seems like you made the right choice with the nibbler.

Dave

Click to expand...

You will find that the nibbler will do a great job and make a great cut. You will also be able to use the nibbler in any other project that might require a curve or corner cut, and it will do it with ease.

Why not use something like this if you're doing a lot of it?

http://www.mytoolstore.com/milwauke/6370-21.html

2"x4" hole? 4" angle grinder w/cutoff wheel, and a steady hand,:thumbsup:

I just tried some shears yesterday..

Ok on a flat straight run, forget about corrugated:no:

I think that Makita nibbler will probably do what you need, but you may find it to be a little on the hefty side. I have its sister, the JS3200 shear and it is the 800-pound gorilla of metal shears. It slices through 10-Gauge or 1/8” mild steel plate like beer cans, but I’m still always amazed at how easy it is to control and make clean, perfectly straight cuts or even small circles with no rippling or distortion of the metal.

Maybe something else to look into if your just making smaller holes for electrical outlets, is that RotoZip now makes bits specifically for sheet metal, but don’t know for sure if they will handle 12-Gauge.

You won't be sorry you went with the nibbler (that's a decent price, too). Metal saws are best used on the thicker stuff that you can get with a shear or nibbler because of the noise and flying chips.

I forgot my sawzall and did that the other day...lemme tell ya:

Grinders are called grinders for a reason; that is they grind sh!t very well. There was no small amount of blood lost when cutting sheet metal with them.:laughing:

2"x4" hole? 4" angle grinder w/cutoff wheel, and a steady hand,:thumbsup:

Click to expand...

Agreed, it works okay for a little bit of cutting. But for real quantities like we had on that job, and what i think Plazaman is doing, you need something better.

Click to expand...

Well said, must be my scottish blood speaking.

Skill saw with abrasive blade = very slow, dusty, smokey, sparks, blades wear very very fast.
Grinder, same deal...


Best Best Solution so far....... Jig Saw with metal blade! Almost cuts like butter, no smoke, no dust, no sparks.

Im going to try to cancel the order on the nibbler, on monday.

Yeah, the more I thought about that... The siding we were working with was maybe 18-16 ga at most. Abrasive blade wear was definitely noticeable, but acceptable. 12 ga, probably not.

Good luck on canceling the nibbler. But if you have any real quantity of that stuff to cut, I guarantee that a good shear will run circles around a jigsaw. Never tried, but maybe you could rent one?

plazaman said:

Skill saw with abrasive blade = very slow, dusty, smokey, sparks, blades wear very very fast.
Grinder, same deal...


Best Best Solution so far....... Jig Saw with metal blade! Almost cuts like butter, no smoke, no dust, no sparks.

Im going to try to cancel the order on the nibbler, on monday.

Click to expand...

The little nibbler I used cut without burring like you get from a jigsaw or sawzall, not sure if that's worth anything.

actually the cuts are pretty clean surprising. They dont have to be clean, the wall will be laminated with 5/8ths rock. I'll try to cancel it, if not oh well.. another to the collection, lol.



is a nibbler loud? (working in an occupied building)

I only used a little tiny ones and they emit a buzz. Not really loud by any means. But I can't speak for a big one.