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- Joined
- May 5, 2013
- Messages
- 309
I have been cutting aluminum on a table saw for 35 years. Mostly for cabinet shop projects. We always used about an 80 tooth carbide tipped blade, with a triple chip grind on the tooth. Cut offs with the miter guage are usually pretty easily done. Ripping along a fence is a little worse, but I would not hesitate. Keep the blade low and material tight to the table. Kick backs are more likely, than with wood. A raised blade will tend to hold the material down, but is far more dangerous with aluminum. Have cut brass as well.
Recently was building a roof with steel roofing. I have cut the steel roofing (29 ga) with a Milwaukee skill saw with the blade reversed with good results. This time I bought a "double cut saw" from HF. It has 2 blades that spin in opposite directions, it worked about the same as the Milwaukee. I would not let anyone do what I did with these saws, that I did not feel had as much experience with these type tools as I do. Possibility of kick back is great, make sure your paying close attention to what your doing and be ready at all times for the kick back. I did all the cutting for a 12' x 45' roof with a hip at each end. There was a fair amount of cutting for this steel. Again if you are not experienced or confident with this type work, it can be very dangerous.
Recently was building a roof with steel roofing. I have cut the steel roofing (29 ga) with a Milwaukee skill saw with the blade reversed with good results. This time I bought a "double cut saw" from HF. It has 2 blades that spin in opposite directions, it worked about the same as the Milwaukee. I would not let anyone do what I did with these saws, that I did not feel had as much experience with these type tools as I do. Possibility of kick back is great, make sure your paying close attention to what your doing and be ready at all times for the kick back. I did all the cutting for a 12' x 45' roof with a hip at each end. There was a fair amount of cutting for this steel. Again if you are not experienced or confident with this type work, it can be very dangerous.
- Joined
- Sep 24, 2014
- Messages
- 926
I have worked in the commercial window business and using a large cabinet table say with infeed and outfeed tables was part of everyday fabrication. We had a very high quality fine tooth carbide blade that was kept very sharp ( we had three blades and would send one out for sharpening and one in reserve) and use copious amounts of WD40. Feed rates should also be very slow and the use of guide and push blocks is recommended. We also had a full face shield along with the safety glasses that everyone was required to wear. I would also suggest hearing protection as there is a very loud high pitch noise created. Following those simple guidelines we never had an injury. We passed numerous state and federal safety inspection as well as insurance carrier liability inspections.
- Joined
- Aug 14, 2014
- Messages
- 81
UNDER NO CIRCUMSTANCES should you turn the blade backwards to cut Aluminum. NONE!
Ditto, missed the move. Certainly agree that cutting Al, or anything other than wood, on a tablesaw with a blade intended for wood is something to be careful of. I use the Diablo blade mentioned above, specifically designed for non-ferrous metals, and it works well. I also routinely do a partial thickness cut on both sides (table saw fence keeps the cuts lined up), aiming for a thirty-second to a sixteenth thick center bridge- which is easily broken or cut. That approach avoids flying chips (they all stay under the table). A jigsaw cuts and a file cleans up the edge just fine.
As with other posters, this is my go-to method for sheet stock -up to half inch or so- too big for my regular saw. If you use all the PPE -eyes, ears, pushblocks- and the right blades and speeds, the method works. It does require more care and thought than cutting wood!
Just for fun, I put a 7.25", 80 flute milling cutter with a 0.25 DOC and 0.125 WOC cutting 6061 into Gwizard. Gwiz comes back with 300 rpm recommended, chipload per tooth .0016, and a feed of 37 ipm for 'light roughing' with HSS cutter. Carbide is about 720 rpm. Plug in 1500 rpm, feedrate jumps to 90 ipm for either carbide or HSS (that is, maxes out- not the actual number allowed) with a thou or so per tooth, at 5000 rpm chipload is 2 tenths. Could be the biggest problem cutting Al on an unmodified table saw is going too slow and rubbing rather than cutting. The Gwiz numbers do suggest that one ought to look at the blade speed, and almost certainly slow it down.
I cut aluminum plate regularly on my table saw. I usually use a non-ferrous blade made for the purpose and have cut up to 1.5" thick material w/o any problems. As mentioned above, it does make lots of chips and they are hot. The biggest problem I have with the chips is that they tend to get tracked into the house and not everyone who lives here is happy about that. I pay attention and always have kickback on my mind, but I have never had it happen. I recognize that it can and stand off to the side so I won't be in the path should it occur. For regular alloys like 6061-T6 and other relatively hard stuff I cut dry. For dead soft things like some castings I cut up some time ago, I use WD-40 to help the chips not stick to the blade. I find aluminum cuts very well on the table saw and its a good way to reduce large pieces down to a manageable size quickly and with reasonable accuracy. It cuts at about 1/2 the feed speed of hardwood. I also have a junker saw fitted up with a Diablo steel cutting blade. I've cut some 1/8" mild steel on that, but it is not pleasant to use and I do so only if there is no viable alternative.
Any metal cutting activity has some risk and they can be mitigated by thinking about what you are going to do and paying attention while you are doing it just like using a chain saw or driving to work. So, for me, cutting metal on the table saw is a good alternative to other methods. That doesn't mean that I'm endorsing or recommending it for anyone else. You will have to make that decision on your own.
Any metal cutting activity has some risk and they can be mitigated by thinking about what you are going to do and paying attention while you are doing it just like using a chain saw or driving to work. So, for me, cutting metal on the table saw is a good alternative to other methods. That doesn't mean that I'm endorsing or recommending it for anyone else. You will have to make that decision on your own.
- Joined
- Jul 7, 2014
- Messages
- 9
I have cut a lot of wood on the table saw that is HARDER than 6061 aluminum (Argentine lignum vitae, ipe, Australian gidgee, etc.). I've also cut 6061 and 7075 up to 1.5" thick in one pass. This is on a smallish Craftsman portable table saw, nothing huge or high-end. I've also cut a whole lot of 2" square 6061 on a chop saw meant for wood at work, because that was the best and fastest way to do it.
The first thing you must understand is that the table saw is usually the most dangerous machine in the shop, even when it's being used for what it's intended for.
What makes a table saw dangerous when cutting wood is that the workpiece is not clamped down and is trapped between the blade (which is spinning towards the operator) and the fence. Wood has a lot of internal stress in it, and it moves when you cut it. If it moves in such a way that it no longer fits between the fence and blade, it can catch the blade and come at you. This danger is practically non-existent when you're cross-cutting, because you aren't using the fence.
Aluminum does not move like wood does, and it's much more homogenous, no grain lines and rarely any hard spots, so it's actually much less likely to kick back than most of the exotic hardwoods I've cut. The surface speed is too high and the chipload is too low for aluminum (this is also true for hardwoods, BTW), but all that means is the blade will dull a bit faster than you'd like. Really the only hazard with aluminum that's any worse than with wood is the possibility of chips welding to the blade. Use lots of WD-40 and sharp blades, and that won't be much of a problem. I've found that aluminum on the table saw is actually not very sensitive to feedrate, though my blades tend to last longer, leave a better finish, and stick to the chips less when feeding a whole lot faster than you would expect.
I would say that cross-cutting aluminum on the table saw is dramatically SAFER than ripping hardwood on the table saw.
The first thing you must understand is that the table saw is usually the most dangerous machine in the shop, even when it's being used for what it's intended for.
What makes a table saw dangerous when cutting wood is that the workpiece is not clamped down and is trapped between the blade (which is spinning towards the operator) and the fence. Wood has a lot of internal stress in it, and it moves when you cut it. If it moves in such a way that it no longer fits between the fence and blade, it can catch the blade and come at you. This danger is practically non-existent when you're cross-cutting, because you aren't using the fence.
Aluminum does not move like wood does, and it's much more homogenous, no grain lines and rarely any hard spots, so it's actually much less likely to kick back than most of the exotic hardwoods I've cut. The surface speed is too high and the chipload is too low for aluminum (this is also true for hardwoods, BTW), but all that means is the blade will dull a bit faster than you'd like. Really the only hazard with aluminum that's any worse than with wood is the possibility of chips welding to the blade. Use lots of WD-40 and sharp blades, and that won't be much of a problem. I've found that aluminum on the table saw is actually not very sensitive to feedrate, though my blades tend to last longer, leave a better finish, and stick to the chips less when feeding a whole lot faster than you would expect.
I would say that cross-cutting aluminum on the table saw is dramatically SAFER than ripping hardwood on the table saw.
- Joined
- Aug 19, 2013
- Messages
- 764
Just for fun... Talking about inviting Mr Murhpy (murphys law) to your shop...
Kinda like: The worst thing that could happen... probably will... LOL
Seriously... if anyone is gonna be 'adventurous'... think it through before setting up and starting the saw.
And one more thing... Have your cell phone in your pocket... just in case you need to call 911...
OK,
As long as we can pick on Murphy, I'll risk identifying Koslowski's Law (Koslowski does not really exist) which states basically that Murphy was an optimist !
- Joined
- May 20, 2014
- Messages
- 191
Boy, am I glad this thread got started.
I have a 9" disc sander with a 1/2 thick, 14" wide, 8" deep tilting table of 6061 aluminum. I need to cut a mitre slot about 3/32" deep and 5/16" wide in the thing. I have no milling machine for this, but do have 2 table saws and some fine-pitch carbide blades. This would probably require some sort of 'finger follower'. I suppose that I should cut the 2 outer kerf slots first, so the blade won't distort, then finish up with hogging out the center portion?
Been pondering on this for quite some time, so I'll just keep watching this thread for now...
I have a 9" disc sander with a 1/2 thick, 14" wide, 8" deep tilting table of 6061 aluminum. I need to cut a mitre slot about 3/32" deep and 5/16" wide in the thing. I have no milling machine for this, but do have 2 table saws and some fine-pitch carbide blades. This would probably require some sort of 'finger follower'. I suppose that I should cut the 2 outer kerf slots first, so the blade won't distort, then finish up with hogging out the center portion?
Been pondering on this for quite some time, so I'll just keep watching this thread for now...