Whats the best way to go about cutting sheet metal?
I have been using tin snips and filing/grinding down afterward, or sniping then bending sections till stress failure (makes nice neat lines).
Both these methods are slow and give fairly crap results , I've been cutting up the old doors to a shed to rehinge them (htey were on runners) because it was a feed shed and the hungry gorses trashed it . Not a biggy but i know there are some awsome fabricators on here and i wondered how it should be done properly (flattery will get you everywhere )

David

Jigsaw with a metal cutting blade. If you have the right blade and dont force it, it is fairly quick. Alternatively, use a slitting disc in a grinder, these are 1mm thick and can be very accurate on straight runs.

used both before, but this stuff is uber thin and just bends (it blows around in the wind ) aside from never use cheap nasty thin metal what might work (with the fin stuff)

http://en.wikipedia.org/wiki/Sheet_metal_shears

I have a set of these and they are very good even on fairly tight radii. If you get hold of a pair, keep the blades sharp and never lose the 4 thin shim washers from the pivot shaft on the moving blade. I lost 2 of mine and they were very hard to get as replacements. Without them it is useless.

If it flexes too much for the jigsaw, clamp a sheet of hardboard or whatever to it and cut through them both together.

I'd use plasma personally.

Al.

I use a drill powered nibbler.... Not the greatest of edges but hassle free cutting.

Similar to this...
Nibbler type jobbie

Buy yourself a GABRO Cutter.

Floor Mounted with a Workbase, they will cut very neatly, if you can find one there not too spendy and don't take up mauch room

They are limited to thickness as to what they will cut, but for thin sheet superb

Nige

10mm isn't thin Nige

(just trying to get me own back for getting me with your april fool )

cheers guys, wish i had asked this before i cut now would saved a fair bit of hassle, but now i know for the next time it gets smashed

David

For cutting up big sheets of metal I find an air chisel (very similar to the one below) works rather well, though its not so effective on cutting up cars or small peices where there can be too much give in tthe metal and can buckle a whole area rather than shear a strip out. The tool for shear in sheet metal is the 2nd one down.



For cutting up car wings etc. then a nibbler in the electric drill works quite well, though has its limitations.

I have one of these, will cut profile sheeting including box profile and sheet up to 1.6mm.

Hitachi CN16SA 400W Nibbler

Depends where I am and whats at hand.

An air shear is great, thats the power tool which cuts out a strip.
Mondex manual version of the air shear, good tool to have around, keeps those wrist muscles in tone.
I do have an electric version, it's like an angle grinder but has a snout like the air shears, I have never used it as it's for plaster[broken bone type plaster] and I keep expecting the owner to ask for it back..

Aviation shears, ones with lots of offset and a gap at the begining of the blades. A stand selling these at a racecar show was demonstrating them by cutting heart shaped bits out of sheet!!! I never replaced that type and haven't seen them since but any good aviation shears work OK. I have never used the yellow handled ones, but they are worn! I use the green ones most but a pair[red and green] is best.
Normal old tinsnips, never really liked them but they work.

air nibbler, fantastic tool. love walking on peoples carpets after using one;-) I probably used a nibbler most cutting bits of panel. The punches wear and need replacing quite regularly, the anvil also needs replacing every so often otherwise they don't cut worth a damn.

Before buying nibblers or shears check on the prices of replacement parts, once the bits wear the tools are really useless.

Bolster, great for cutting panel when your in a scrap yard.
diamond shaped chisel, probably a brickies tool? with a bit of grinding you can make it cut a bit like the air chisel a previous post suggested, it's another tool thats usefull when there's no power around.
Another tool I would put in the same class is some knife I have, it has a parallel thick blade and the handles are bits of thick leather riveted on, I have no idea of it's intended purpose but if you can get it into a panel you can hammer it along... All sounds a bit grusome, quite often I bought body sections and had to cut them off without any power
and I used to use an assortment of tools, reminds me a bricksaw can be really usefull..

Air chisel, sometimes it's the tool for the job.

Bench knife, big shears mounted on a bench, wack 6 foot of scaffold on the handle and it will cut 1/4" plate, but it will also cut sheet very effectivly.

plasma, the way to go a lot of the time..

Hacksaw, fantastic tool. high blade tension and good blades[eclipse] is the secret to the hacksaw, get a Lennox hacksaw frame and you will understand the frame makes a difference. a sheet metal hacksaw isn't that difficult to make, or an extended frame one..

Cengatte saw, fantastically usefull on car panels and now and again it's the only way to cut something but isn't very quick.

Jigsaw with a eclipse hacksaw blade, pretty good on sheet. I have cut 1" ali with mine.

I have a couple of those. Need to watch out for the little crescent bits of waste that come out of it, they are razor shar and spikey.

They like nesting in carpet! And cadging a lift on the sole of your shoes.

I have a pneumatic nibbler, the bits are also good at puncturing cycle tyres...

AS Integerspin says,

"Jigsaw with a eclipse hacksaw blade, pretty good on sheet. I have cut 1" ali with mine"

I'll go along with this one. I used the light blue flexible HSS blades cut into 3" or so lengths and then trimmed to fit my 50p car boot jigsaw.

I was cutting 20g sheet, clamped to my B&D workmate with a bit of 2" angle as a guide.

Very fast, accurate and CHEAP!

Bob

I normally reach for the air hack saw now, rather than the manual version. It's good, as long as you can hold the work solidly enough that it doesn't just vibrate with the blade.

Hand operated nibbler is fine too.
Mine's a Clarke one, like this;

Cheap as chips and whips the roof out of an Escort in 10 mins with a nice neat no-buckle finish.