Need advice on cutting aluminum square extrusions
 

hey guys, I have some 25 mm aluminum extrusions bars that i need to cut to size. (just straight cuts chopping the bar, no angles) I went to home depot and they have these cutoff wheels for metal.

Diablo 12 in. x 1/8 in. x 20mm Metal Cutoff Blade-DBD120125G01F at The Home Depot

They also have this much more expensive blade
Freud | FREUD 7 1/4 In. Metal Cutting Blade - 48 Teeth | Home Depot Canada for cutting metal.

Which blade would be better for my purpose? The blade will have to fit on a table saw because that is the only cutting tool I have.

Thanks for the help and any safety tips would be appreciated!

I would to a welding supply shop and look at aluminum cutting wheels. The second one says specifically for Ferrous metals/steel. I would go to like a flea market or on craigslist and look for a chop saw. You don't want to use the table saw for these kind of work as it can easily come out crooked or bend the aluminum. Better to fasten down the workpiece and move the tool than the other way around. Bring those extrusions with you and they will recommend the best way to cut it.

how may cuts?

Would the first blade work though if I was really careful?
I should have mentioned that the bars are of this type http://img4.fastenal.com/productimages/0956827.jpg

thanks for the advice, having the workpiece fasten down does make more sense. lol

I think maybe about 30 cuts because some of the rods need to be trimmed due to poor existing finishing.(The extrusions used to be part of some cage)
I was hoping to cut some to as sort as 10 cm without it warping.

it's aluminum which is super soft, i don't see why a vice and a hacksaw wouldn't be good enough for your needs, any power tool is overkill, those blades are really meant for chop saws and not table saws, sometimes the best solution is the simplest and safest solution

You can use wood cutting tools on aluminum. Tablesaw, chopsaw, router etc. For a few pieces any wood blade and some wax will do. Safety glasses.

I would cut it in this order milling machine, chopsaw, radial arm saw, bandsaw if you want a nice edge. Any abrasive type of cutting is garbage in my opinion.

You can do it on your tablesaw with a technique that will take too long for me to describe.

hmm...... I will try that tomorrow to see how it goes. From my past experience with a hacksaw, I am not confident I will be able to cut it very straight. The new pieces will have be butted together in a T shape, and I need it to be perfectly perpendicular. I was hoping a mechanical saw would be able to cut better square edges.

what do you mean by wax on the wood blade? I tried to search up that term on google, but I couldn't find any relevant information. Does your cutting technique have a name so that I may look it up?

You can get cutting lubricants in a wax like stick. Then rub the wax wherever you are going to cut on the aluminum. I remember using some green stuff made by walter I think. Or a9 aluminum cutting fluid is crazy stuff too.

After seeing your extrusions forget about the table saw method. I wouldn't do it myself unless it was a last resort so I'm not going to recommend that method.

Also don't use a fiber type wheel like the first one as they can clog with aluminum then you will push harder on the saw and then the wheel will shatter and go through your cheek.

If you have 25 to do and need a square edge I would just go to a railing shop close to closing time with a case of beer.

You are going to lose fingers. Possibly an eye.

listen to sdubfid...he wants to keep you intact.

Havent read thread... but I cut my aluminum with a wet tile cutter.... if the pieces are thick, you may not want to have your face and neck exposed incase the blade breaks.

Interesting. I never would have thought of that.

Now I kind of want to try it.

25mm is pretty small for aluminium extrusion. You don't want to use a table saw with those because of the torque may make pieces go flying.

Are the extrusion part of a T slot setup? If so, hand saw or cutting lubricant eg with a cold cut saw will not distort the slots.

Use a handsaw if you want to be safe.

If you have to cut a lot of cuts. Use a $20 CT grinder, gloves, clamps AND full face mask. Mark the Al with plenty of leeway and grind away.

Either way, I hope you have a sander to finish the cut. Tip: score a metal line on your final dimensions (don't just rely on sharpie etc).

Use a square and mark all the way around the stock to ensure squareness when using a hacksaw.