Cutting sheet aluminum with a skill saw. I'm doing it wrong.

[pwschuh]

Just picked up an 18V cordless skill/saber saw after not having one for several years.

I need to cut some shapes out of 11 GA (.225 in) sheet aluminum (6061).

I was using a Bosch T118A ("Basic Metal") blade and failing miserably.

I had the oscillation control set on 0 (for no oscillation) as recommended in the user's guide for aluminum (and other metals).

I started out going too fast because I trashed one blade almost immediately by filling up the teeth with aluminum that would not brush out, even with a steel brush.

I tried a new blade and went slower and it went a little better, but still poorly. Saw blade would catch on the metal and cause the saw to jump out of the cut. The blade still clogged a little but I was able to catch it earlier and clean it out with a brush.

I was making very slow progress and decided to stop until I figured out what I was missing.

Am I using the wrong blade?

 

[tyyost]

Yes, wrong blade. Way too high tooth count for the material thickness. The blade is designed for very thin materials in ferrous and non ferrous metal. Try a T127D blade and you’ll see the difference.

 

[tinbender 66]

Put some beeswax on the blade too.

 

[Jeff Ivers]

I spray my blades with teflon lube when cutting aluminum. Also, when the blades do clog, I clean them on a powered wirewheel and then reuse them.

 

[jack stand]

It's hard to beat a regular (circular) skill saw with a regular carbide woodcutting blade for straight cuts.

 

[tarbellb]

WD40 is a great aluminum lube substitute as well.

Agreed with other statements, more aggressive tooth count (less), sandwiching helps, as does really clamping the snot out of it.

 

[pwschuh]

Thanks for all the inputs. I'll get some new blades. Can't sandwich it because I have to cut following some curved designs that are drawn onto the aluminum. I could clamp some (thin) wood to the bottom though. Don't have beeswax but do have WD40.

 

[The Cobbler]

as fine tooth blade s you can find, go slow, lube, don't get jerky motions

 

[metlmunchr]

The OP needs to define what he's cutting. 11 ga aluminum is .091" thick, and not .225". If it is 11 ga then his current blade is okay. If .225" is correct then the 8 tooth blade recommended up above would be good.

You can spray some wd-40 along your cut line prior to cutting, or some thin oil like 3 in 1 will work too. If there's a glass shop nearby, they'd likely sell you a wax lube stick as they all keep it for lubing miter saw blades when sawing aluminum extrusions for glass frame fabrication. When cut dry, aluminum will stick to just about any cutting tool you'll find.

 

[theoldwizard1]

Sandwich between waste wood and you can use any blade you want(within reason disclaimer).

Sandwich it even when you have the right blade.
It's well worth the cost and waste.

This !

 

[bobabuee]

my take on this 18V cordless skill/saber saw might not be up to task depending on brand?

i always use a corded jigsaw, with right blade, more aggressive blade i am in sign industry use bosch T227D 8 tpi

make sure right tooth blade for this, lube it up cut slow rather than fast. dont push let blad do the work, the object is not to let blade get hot ,you can even spray water on surface, if see blade getting gummed up stop wire brush the blade

 

[pwschuh]

The OP needs to define what he's cutting. 11 ga aluminum is .091" thick, and not .225". If it is 11 ga then his current blade is okay. If .225" is correct then the 8 tooth blade recommended up above would be good.

Yes, you are correct. That was a typo in my original post. The sheet is 8ga, .125" thick, not .225".

my take on this 18V cordless skill/saber saw might not be up to task depending on brand?

Milwaukee 2737. Pretty sure it's up to the job.

 

[jeepinerdeep]

as fine tooth blade s you can find, go slow, lube, don't get jerky motions

Negative. He's already on the verge of too fine. Can't clear the chips, that's why the blade loads up. This is a jigsaw not a (Skil) circular saw.

 

[Monza Harry]

Just picked up an 18V cordless skill/saber saw after not having one for several years.
I had the oscillation control set on 0 (for no oscillation) as recommended in the user's guide for aluminum (and other metals).

Skill saw is know as a "Circular Saw" Saber Saw conjures a "Jig Saw" or "Vertical Reciprocating Saw" in my minds view. You would likely do better with the circular saw and aluminum typically likes a coarser blade than will work with steel, for the reasons your are finding out. The oscillation set to "Zero" doesn't seem right to me at all, the blade cuts only on the upstroke [if installed correctly] and dragging it with the down stroke only dulls the blade and adds further heat to an already "Hot Job", Metal cutting LOVEs Lube! The two mentioned above would be a great choice, candle wax would do as well, even some cooking oil if no other choices exist, that will "Season" the blade like a frying pan, ideal (?) less so. But non-stick is = lubricity in some ways. Harry

 

[pwschuh]

Sorry, I said "skill/saber," but I obvioulsy meant "jig/saber." Like I said, I'm not a saw expert and haven't had either kind for a while. I can't use a circular saw since there are no straight lines involved here. I can't argue about the oscillations, only to point out that the saw's user's guide says that metal cutting should use little or no oscillations. The higher oscillation settings seem to be recommened only for wood.

 

[vavet]

Rule of thumb is to have 3 teeth in the material at all times.
If your material s 0.090" thick, the teeth should be 0.030 apart, which means 1/0.030 = 33.3 teeth per inch.
If the workpiece if 0.225" thick, the teeth should be 0.225"/3 = 0.075" apart. 1"/0.075" = 13.33 teeth per inch.