How do you make clean cuts in aluminum?

[6t8dart]

I have to admit that even though I have been building cars for 3 years, most have been american muscle cars. Now the problem, I have hardly ever dealt with aluminum.

How do you make clean cuts in aluminum?

I refuse to use a drill bit and tin snips, I want a clean cut, no curled, ragged edges. Abrasive wheels clog up, as well and body saws, any suggestions?

[chopthebass]

If you want clean round holes you want knockouts, like ones made by Greenlee. Straight cuts you need shears. You can get small bench top ones or large foot operated machines. Depends what you are doing and if the final cut is visible. I have made awesome cuts using Bosch jigsaw blades.

[David Hodgkins]

I cut long lines and curves with a small bandsaw...

:)

[65 Cobra Dude]

A nibbler also makes great cuts.

Henry

[skullandbones]

It's a completely different "ball game" with aluminum. I, like you, had never worked with aluminum except in very small an isolated instances. It acts different than other metals in almost every respect. I've used a hand shear with pretty good results. One side of the metal will bend. You just have to get your technique down so you don't bend the one you are wanting as the finished piece. A good band saw works but you can screw a piece up with it as well. Jig saw with the correct blade works great but tedious. I have started going to the metal shop and retrieving pieces that are either close or exactly the dimension I need at least in two dimensions. I will get them to do the other cut or stop by my friend's fabrication shop so he will shear it (for longer ones). Breaking is also a pain if it's over 30 inches. Depending on the application, you will have to use different strategies. Unless you have a complete machine shop at your disposal, you will have to be somewhat creative.

Good luck,

WEK.

[jlfernan]

3M makes a great polishing wheel you attach to a bench-top grinder. Once you cut the piece you use the wheel to deburr the edge. Smooths everything out and less chance of cuts.

http://www.cleavelandtool.com/3M-Cut-Polish-Wheel-6/productinfo/3MW7A6/#.VdtNXvmrRhE

[Gumball]

For straight cuts, I like to use an old foot shear that a friend has at his shop. For smaller cuts, I use either my band saw (back the material up on wood or something if it's thin), snips, knibbler, or a dremel (with a variety of attachments - cutting wheels and circular cutting bits, which sort of look like really sharp drill bits with a very mild twist).

[edwardb]

Sounds like my experience is similar to others. I use a small bandsaw with a metal cutting blade whenever possible, and a handheld jig saw with a metal cutting blade for the big stuff that won't fit in the bandsaw or has inside cuts. Then clean/straighten the edges using the disk sander on my Delta disk/belt sander. A couple of swipes and they're perfect. For inside curves, clean and straighten with various side drum sanders in my drill press. I'm on my third build working this way, and have done quite a lot of fabrication including duplicating or replacing numerous panels. I also use a very cheap little 30 inch Harbor Freight brake. Keep threatening to get something better than that, but so far it's met my needs. Bottom line, .040 aluminum (most of what's used) is quite easy to work with. A shear would be nice, but I can't justify that. Tried a nibbler, and it works OK. But little pieces flying everywhere and my bandsaw/jigsaw process is quicker and easier for me.

[MPTech]

As others said, for most cuts I use a good jigsaw and fresh metal blade (liberally sprayed with WD40 as I cut).
For long straight cuts, I measure and clamp a straight edge to my bench and just run the jigsaw cleanly down it.
Carefully follow that up with a metal file and a piece of fine sandpaper on a sanding block and you get a great edge!

Be careful working with the aluminum, the edges can cut you badly.

[cChrisM]

As others said, for most cuts I use a good jigsaw and fresh metal blade (liberally sprayed with WD40 as I cut).
For long straight cuts, I measure and clamp a straight edge to my bench and just run the jigsaw cleanly down it.
Carefully follow that up with a metal file and a piece of fine sandpaper on a sanding block and you get a great edge!

Be careful working with the aluminum, the edges can cut you badly.

What MPTech said. WD40 allows it to cut like butter and does not gall up the cutter. If you need perfection, cut a little wide and a nice file will make short work of getting it perfect.

[RRussellTx]

WD40 works good but I think Anti-Spatter spray works a little better to keep the cutting tool clean.

[CraigS]

For small round holes up to about 7/8 a step drill bit works very well.
http://www.homedepot.com/p/Milwaukee-3-16-in-7-8-in-x-1-16-in-12-Hole-Step-Drill-Bit-48-89-9130/203115429
For long cuts I use same as most. Bandsaw or jig saw w/ fine tooth blades followed by file or sanding block. Always wear gloves for the finishing process.

[smokinss]

A nibbler also makes great cuts.

Henry

I prefer the Bad Dog Biter type of nibbler. I got mine at SEMA several years ago and it is a miracle cutting device. Curves, straight and circles. Cleaner cut than plasma cutting and no sharp edges like cutters. You drill a hole to start and then insert the nibbler. Other brands are as cheap as $40 on Amazon. The Bad Dog is over $150. But worth every penny when cutting aluminum.
Here is a link to the YouTube video showing it in action:

https://www.youtube.com/watch?v=6mc9dvGF6S8

I wanted an access panel on my driver's side footbox but with the body on I could not remove the cover. I cut an oval hole instead with the Bad Dog biter and used the removed piece as a template for a slightly larger oval to cover the opening. A saber saw or my band saw leaves a ragged edge, but this is so smooth.4473444735

[beetlespin]

I prefer the Bad Dog Biter type of nibbler. I got mine at SEMA several years ago and it is a miracle cutting device. Curves, straight and circles. Cleaner cut than plasma cutting and no sharp edges like cutters. You drill a hole to start and then insert the nibbler. Other brands are as cheap as $40 on Amazon. The Bad Dog is over $150. But worth every penny when cutting aluminum.
Here is a link to the YouTube video showing it in action:

https://www.youtube.com/watch?v=6mc9dvGF6S8

I wanted an access panel on my driver's side footbox but with the body on I could not remove the cover. I cut an oval hole instead with the Bad Dog biter and used the removed piece as a template for a slightly larger oval to cover the opening. A saber saw or my band saw leaves a ragged edge, but this is so smooth.4473444735


Great find and well worth the money !!!!

[sbak]

I used to work for an engineering company which manufactured big equipment for the printing industry. The guys in the machine shop would use a shear but sometimes they would sandwich the thin aluminum between two sheets of 1/4 plywood. If it were a curved shape they would glue a CAD drawing to the top sheet and using clamps to keep it all sandwiched, cut it out with a jig saw (or for old guys.. saber saw). Clamp a straight edge on top for a straight cut. The wood seemed to 'clean' the blade as it cut and there was no bend on the bottom side which, in my own experience using a shear, you can get. I've used this method on thin aluminum and stainless ever since.. and it has worked well. Keep it clamped tight so you eliminate the vibration and you should have a smooth cut.. use a really fine blade I think I even found some at one of the big box stores or the hardware store that say for aluminum.

[rlampman]

I have a nibbler, band saw, and a cut off wheel. I don't use any of them any more. I have found I can make the best cuts with a fine tooth jig saw leaving about 1/16" extra material. For small trimming or close areas I use hand tin snips leaving more extra material because of the jagged edge. Then I use a course file and then a fine file to bring the cut right where I want it. If you keep the file at a good right angle and then deburr the edge it can be hard to tell what edge is the original uncut side. Somewhat more work but the file makes quick work of the aluminum and it is much easier to be precise. I have a selection of flat and curved files that work great. Always use gloves as the edges will cut you bad. Specially when using the file. I have not used WD40 for the blade but will try that one next time.
Rod

[rich grsc]

For straight cuts, I don't cut it with anything, score it with a $.99 scorer from HD or Lowe's. It will just snap clean. For everything else a fine tooth jigsaw and lots of WD-40

[RogerB]

Does anyone have any experience with this nibbler from Harbor Freight? I was considering it but sounds like there are a bunch of great ideas out there..

http://t.harborfreight.com/16-gauge-air-nibbler-96661.html?utm_referrer=https%3A%2F%2Fwww.google.c om%2F

[rlampman]

Does anyone have any experience with this nibbler from Harbor Freight? I was considering it but sounds like there are a bunch of great ideas out there..

http://t.harborfreight.com/16-gauge-air-nibbler-96661.html?utm_referrer=https%3A%2F%2Fwww.google.c om%2F

I have that one. It works good on the .040 6160 aluminum. I have also used it on .090 5150 aluminum but you have to keep it very vertical as an angle can make it jam. After a really long cut in the thicker aluminum you also have to take apart the tip and clean out. The thicker and softer aluminum galls up. I found that without some type of guide like a strait edge or another piece to keep it against it is hard to keep a smooth strait cut. Hard to keep strait without wandering small amounts. The .040 material is much easier but still needs some type of fence. With a fence to keep the line strait it makes a real clean cut but still needs some clean up with a file. Not much at all though. I think the tool works great but I haven't used mine in quite a while. All the scrap it makes makes more of a mess than the dust from a saw. See my method above on post #16.
Rod

[6t8dart]

A lot of good advice, I did make a dash panel before with thin aluminum and scored it for clean cuts, but cutting the gauge holes with a body saw was a marathon event. I think I might invest in a small bench shear, I hate using tin snips.

[BigUgly]

A circular saw with a new carbide tip blade. The first time you try it it is a little scary as you bring yourself to slowly feed that blade into the aluminum sheet, but then when you see the beautiful clean cut you made, you'll wonder why you haven't been doing it this way all along.

BigUgly

[flynntuna]

A circular saw with a new carbide tip blade. The first time you try it it is a little scary as you bring yourself to slowly feed that blade into the aluminum sheet, but then when you see the beautiful clean cut you made, you'll wonder why you haven't been doing it this way all along.

BigUgly

What type of blade, how many teeth?

[BigUgly]

flynntuna,

in my 12 inch radial arm saw I use a 70 tooth carbide blade, more teeth equals a smother cut, in my circular saw I would have to go out and check how many teeth, but more teeth makes a finer cut.

BigUgly

[bmcglone]

I used a combination of snips and a file to dress the edge, dremel, and cut off wheel depending on the application. A for shear would have been nice.

[VdubJoe]

I use a 12 inch northern tool shear. Wiss snips work very easy with a little practice. Jig saw. Band saw with metal blade. Just about any wood cutting one will cut alum. but not slow enough for steel. And I love my just acquired plasma cutter.
Here is an excellent link for using snips. Makes it a whole lot easier. https://www.youtube.com/watch?v=qAOQfUaRZyw