I'm planning to make a cold air box from thick aluminium checkerplate which requires the cutting of curves and a circular hole for the air filter's hose/pipe.
Cutting out circles with a jigsaw/dremel/files is a lot of work and it's much better/faster to use a holesaw but these are expensive for what will most likely be a one-off use.
The same goes for cutting curves, if you're anal like me, you end up spending a LOT of time with a file to get it right.
I found the "Professional Nibbler" after a few web searches which looks ideal for these types of jobs and will definitely be used more than once:
It attaches your drill and:
"The Professional Nibbler can be used free hand or bench mounted. It will cut mild steel, stainless steel, colour bond and corrugated iron quickly.
On colour bond (corrugated iron) it will not scratch the paint, no sharp edges, and no sparks. It doesn't generate heat so rust will not occur unlike when using the grinder.
That's why it's widely used by plumbers, roofers, car restorers and the DIY sector.
The Professional Nibbler allows you to cut guttering, trim deck, mini orb and car body work with ease. You can cut out internal holes for down pipes, sky lights chimney flutes and more. You start in the middle of a sheet, drill a 10mm hole, place the head of the Nibbler in and start cutting away."
See http://newstyledirect.com.au/Professional-Nibbler
There's a video link on the page.
It's Australian made too!
