BMcD
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Will it ruin my plywood blade to cut T slot with it?
How to cut aluminum extrusion?
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heada
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I'd use a low relief rip blade vs an alternate tooth bevel cross cut blade like a plywood blade. You want as much support behind the carbide teeth as possible.
I’ve used a regular hacksaw in a miter box which worked well. Made 6 cuts without issue. Used WD-40 as cutting fluid and to keep the flakes contained.
If you use an electric saw, you want low RPMs.
Tony
If you use an electric saw, you want low RPMs.
Tony
beantownJPL
Up up and away... Wait! Come back!
My dad uses a lot of aluminum extrusion. He either cuts them with a carbide chop saw blade, or an abrasive blade.
caveduck
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I've been cutting extrusion and bar stock up to 3-4" diameter with a cheap Chinese 14" chop saw with an abrasive wheel, but that's 3500 rpm, slow cutting and not very precise...have been looking for something better. I'd definitely recommend using a metal-cutting blade with higher tooth count v a plywood blade. You didn't say what kind of saw you're using but generally you want 2-3X lower RPM than for wood. I found a reference recently to the DeWalt DW872 saw which is 1300 rpm and for which you can get a toothed blades specifically intended for aluminum and steel. It has lots of good reviews. The Fein Slugger 14" metal cutting saw is also similar in price and specs, and there's a Makita one that looks an awful lot like the Fein and is slightly less expensive. There are a few saws you can look at from Evolution including a 2500 rpm 10" sliding miter saw, which is noticeably less expensive and more capable in terms of stock dimensions. For all of these you really need to get the right metal cutting blade.
If you have a few cuts, buy a hack saw. If you have a lot of cuts, buy a metal cutting band saw. Otherwise as stated a chop saw will work well, as will a cut off saw with fiber wheel. I use a vertical band saw with fine tooth blade, 20 tpi.
vcp
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The cheap HF metal band saw that I got second-hand is slow and finicky, but it does excellent cuts on extrusion.
Hooked On Rockets
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+1
More teeth, slower speed..
And another cheap tip, before you cut,
Take a bar of soap (used scraps/left over) and spin the blade up and cut the soap to coat the teeth...
That'll help if the blade speed is too high and it'll also help from blade burn-out.
That'll help from galling the blade (that is, the aluminum galling up on the blade).
Circular saw with wood cutting carbide blade has worked for me for many years. Galling "may" be an issue that simple wax, paraffin or beeswax can help with..You can cut 1/4" steel plate with the same simple blade also. Done it many times. Feed and speed is the key. Safety gear is obviously essential..
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I've done a lot of alum fabrication over the years, and as others have stated, using a carbide tooth blade and the correct feed speed are critical to doing it correctly and safely. Definitely use eye protection/and or a face shield when cutting alum because you only have two eyes, and alum is nonmagnetic , which makes getting it removed from your eye more difficult (ask me how I know).
Grown men sometimes turn to jelly and slide out of the exam chair. Please wear protection.
After removal, ferrous metals tend to leave a rust ring behind. Often requires scraping with needle or algerbrush/burr.
After removal, ferrous metals tend to leave a rust ring behind. Often requires scraping with needle or algerbrush/burr.
Most foreign bodies embedded in the cornea are removed with an instrument called an 'eye spud'. There are different versions for magnetic and non-magnetic foreign bodies.
The cornea is anaesthetised, but when the local wears off you'll wish the aluminium extrusion had whacked you in the genitals at high velocity instead of shooting a small piece of metal into your eye.
Step by step, if you're fascinated with this stuff...
https://www.reviewofoptometry.com/article/foreign-body-removal-in-12-steps
The cornea is anaesthetised, but when the local wears off you'll wish the aluminium extrusion had whacked you in the genitals at high velocity instead of shooting a small piece of metal into your eye.
Step by step, if you're fascinated with this stuff...
https://www.reviewofoptometry.com/article/foreign-body-removal-in-12-steps
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Ditto.
rharshberger
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Not to mention the "dremel" tool they take to your eye to "buff" out any rust (steel or iron shards). Dont ask me how I know this....
Oh yeah. I left that out because I didn't want to totally scare people away from cutting metal.
Seriously, I've seen, and done, some stuff. The life of an ER/OR nurse. Buy me a drink. I have stories...
Home centers carry Non Ferris Metal Blades for 7-1/4" circular saws, 10 and 12 inch blades for table saws and miter saws. I kept one in my wood shop, I occasionally used it to cut aluminum and brass. I think mine was a Freud Diablo, contractor grade blade from Home Depot. Different stores carry different brands. All work well and are made to cut aluminum.
heada
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Diablo is one of their lines of blades. I have 3 or 4 different ones I use for woodworking. For cutting aluminum, you can use almost any carbide tipped blade but at slower speeds (about 1/2 is what I remember) Cutting steel takes a special blade.
https://www.diablotools.com/products/D1260CF
Hmm. My table saw only runs at one speed, unless maybe I can hook in a VFD.
KilroySmith
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I've used my radial arm saw at full speed to cut a lot of aluminum - from thin-wall extrusions to 1/4" plate. A carbide wood cutting blade works well, but tends to grab the workpiece and climb on top of it, which isn't good. A non-Ferrous blade has much less desire to gobble up your workpiece, fingers, and arms. You have to carefully control the saw, even pushing back at times, to make it through. And, not only should you wear excellent eye protection (not just a pair of glasses; small, razor-sharp shavings are getting thrown everywhere and bouncing off of everything - wear full-coverage goggles), you should also wear excellent hearing protection, because the noise is like the combined shrieking of all the souls in Hell having a particularly bad day. Also plan on spending 20 minutes with the broom and shop-vac cleaning everything within 10' of the saw, because those little razor sharp shavings get everywhere, and tracking a few into the house will make you a persona non grata.
@KilroySmith I liked the "souls in Hell"... Yeah, I've cut a little aluminum myself and I agree with your safety measures. But when I think of ripping down 3 or 4 ft of square tube, I might indeed become a fan of Meyer's method. The drill press is better for this than the saw. I'm thinking clamp the tube and "L" pieces together with a piece of flat stock between them to get your space the way you want it and drill/rivet, only unclamping when you're done. Should come out pretty nice...
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I've done hundreds of cuts over 10 years.
Fine tooth carbide saw blade in your standard issue chop saw. Use Wax or WD40. Wont mess up your blade for general purpose wood cutting but if you have a really nice blade find something else. I currently use this: https://www.amazon.com/gp/product/B01MU7V346/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Clamp down your work piece well, and wear hearing/eye protection. aluminum tends to 'sing' and can be much louder to cut than the already loud saw. Especially when doing tubing.
Fine tooth carbide saw blade in your standard issue chop saw. Use Wax or WD40. Wont mess up your blade for general purpose wood cutting but if you have a really nice blade find something else. I currently use this: https://www.amazon.com/gp/product/B01MU7V346/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Clamp down your work piece well, and wear hearing/eye protection. aluminum tends to 'sing' and can be much louder to cut than the already loud saw. Especially when doing tubing.
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I was out doing a bunch of stock prep today, and took a pic of my setup:
I have been spraying the blade with WD40 every 20 cuts. This is 1 3/16" 6061 Aluminum. I avoid spraying the metal directly as it just makes the chips and workpiece sticky and hard to clean up.
I have been spraying the blade with WD40 every 20 cuts. This is 1 3/16" 6061 Aluminum. I avoid spraying the metal directly as it just makes the chips and workpiece sticky and hard to clean up.
caveduck
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Updating my post from a year ago...I eventually bought the Fein Slugger 14" low speed ~1400 rpm metal-cutting cold saw and am really happy with it. Not too loud, high quality tool and with the proper blade, eats thru aluminum and mild steel at astronishing (tm) speed. I recently went through some 3.5" round aluminum bar at about 40 seconds per cut, only takes light pressure - no struggle to keep things under control. It also doesn't throw the chips too far. I had a look at the DeWalt metal saw too, but the Fein is a lot more sturdy - especially in the workpiece clamp - for 20% more cost. And you can handle the blanks immediately after cutting. YMMV, I do probably cut more metal than average and rarely cut wood.
