Wrecked Aluminium from chopsaw

[cgmv123]

Originally Posted by AdamHeard

We run a metal chop saw with a blade meant for aluminum and kids have made at least 1000 cuts this year quickly and safely.

Same story here. Training and proper clamping is critical. The clamp that comes with the saw doesn't cut it. As long as you don't go too fast, you'll be fine.

[purduephotog]

Since this was the first post I'd seen on here about this, perhaps the OP could detail:

1) Material being cut (yes, aluminum- but what grade)
2) Orientation of the material
3) Dimensions of the material
4) Size of the cut (and the cutoff piece)
5) Was the material clamped?

Thanks. Would help me appreciate the level of risk here.

[fox46]

A reciprocating saw is not going to cut straight at all, and is far more dangerous than a proper chop saw for metal.

We run a metal chop saw with a blade meant for aluminum and kids have made at least 1000 cuts this year quickly and safely.

Very similar saws can act quite differently. Know the difference!

Hmm, it sure seems to have worked out well for the OP...

I reiterate- just because a tool will do the job doesn't make it the right tool!

A chop saw is NOT the right tool. Chop saws designed for structural tube are called cold saws and typically cost $1000+, have an automatic feed, and run at low RPM to prevent accidents such as the OP's photo. The capabilities of a consumer grade chop saw and aluminum end at things like window screen frames. THIS is a chop saw for structural tube ie: cold saw:



I contest anyone that states a reciprocating saw is more dangerous than a chop saw. How many people do you know have lost fingers to chop saws vs reciprocating saws??

A reciprocating saw will be challenged to make a perfectly straight cut but what are you doing that requires a perfect cut? Welding? Fill it. Anything that requires more precision than a saw cut should be rough cut and then machined.

Acceptable saws to cut structural aluminum:
-Reciprocating saw with bimetal blade
-Bandsaw (vertical) with appropriate blade and blade speed for metal
-Bandsaw (horizontal)
-Cold saw
-Hacksaw

[Cory]

Originally Posted by fox46

Hmm, it sure seems to have worked out well for the OP...

I reiterate- just because a tool will do the job doesn't make it the right tool!

A chop saw is NOT the right tool. Chop saws designed for structural tube are called cold saws and typically cost $1000+, have an automatic feed, and run at low RPM to prevent accidents such as the OP's photo. The capabilities of a consumer grade chop saw and aluminum end at things like window screen frames.

This is not true. Check out the specs on a non-ferrous chop saw. You're looking at ~3,000 RPM.

A previous poster already linked to the DeWalt multicutter, which is specifically designed for cutting solid and tube. Adam is using a similar model. I know for a fact that some professional machine shops use these saws in lieu of a band saw, for cleaner, faster cuts.

[AdamHeard]

Originally Posted by fox46

Hmm, it sure seems to have worked out well for the OP...

I reiterate- just because a tool will do the job doesn't make it the right tool!

A chop saw is NOT the right tool. Chop saws designed for structural tube are called cold saws and typically cost $1000+, have an automatic feed, and run at low RPM to prevent accidents such as the OP's photo. The capabilities of a consumer grade chop saw and aluminum end at things like window screen frames. THIS is a chop saw for structural tube ie: cold saw:



I contest anyone that states a reciprocating saw is more dangerous than a chop saw. How many people do you know have lost fingers to chop saws vs reciprocating saws??

A reciprocating saw will be challenged to make a perfectly straight cut but what are you doing that requires a perfect cut? Welding? Fill it. Anything that requires more precision than a saw cut should be rough cut and then machined.

Acceptable saws to cut structural aluminum:
-Reciprocating saw with bimetal blade
-Bandsaw (vertical) with appropriate blade and blade speed for metal
-Bandsaw (horizontal)
-Cold saw
-Hacksaw

We use a chop saw designed for cutting Metal that has a purpose built blade for aluminum on it. How is this not the right tool?

Yes, a cold saw would be nicer, but it's still on our wish list.

The OP likely was doing something improper and/or using the wrong kind of saw/blade.

We get square cuts off our saw, it's a huge time savings not having to mill ends. I'm in the business of maximizing my students time doing cool stuff (fun machining) and minimizing the lame stuff (hey lets face 200 tubes this season because our saw can't cut straight!). Suggesting we weld nonsquare tubes and just fill the edge is really a poor approach to the manufacturing process.

All the students and mentors cleared to use our saw have been trained, and they use it safely and without issue. Fingers shouldn't be involved in the process at all. Material should be clamped.

For ~$500 we got a saw that was able to cut up to 4" solid with square edges, you'd be looking at likely $5k+ for a cold saw with such capability (which is our next move, we really want one). A horizontal band saw that can compete in speed and squareness isn't really an option either.

Many of out industry professional sponsors running small to large shops run similar saws for certain cuts as opposed to their band saws for the same reason we do.

A reciprocating saw will do the job, but that doesn't make it the right tool

[fox46]

lol alright then, have fun guys.

For those interested in doing things the right way, two options for properly cutting structural tube for less than $400:

USA: http://www.harborfreight.com/garage-...saw-93762.html

Canada: http://www.princessauto.com/pal/en/B...-Saw/8354789.p

For less than $50:

USA: http://www.harborfreight.com/6-amp-r...ngsaw-11142012

Canada: http://www.princessauto.com/pal/Reci...-Saw/8507626.p

[team222badbrad]

Originally Posted by fox46

lol alright then, have fun guys.

For those interested in doing things the right way

I'd love to hear why you think a chop saw DESIGNED for cutting metal is not the right way? That's your opinion and not a fact.

If you use one you will change your mind.

We spend less time cutting and machining using our chop saw designed for metal.

For reference on a chop saw designed for metal here's a link:

http://www.homedepot.com/p/DEWALT-15...W872/203164101

[JamesCH95]

Originally Posted by Cory

This is not true. Check out the specs on a non-ferrous chop saw. You're looking at ~3,000 RPM.

A previous poster already linked to the DeWalt multicutter, which is specifically designed for cutting solid and tube. Adam is using a similar model. I know for a fact that some professional machine shops use these saws in lieu of a band saw, for cleaner, faster cuts.

The DeWalt multi-cutter is a fantastic saw.

In college I used a DeWalt multi-cutter to cut thick-walled alloy steel tubing, thin-walled titanium tubing, galvanized steel angle, all manor of aluminum extrusions, and practically everything in between. It runs at 1,300rpm and has a heck of a good clamp for securing work pieces. Never had a single incident with it.

It's such a good saw that the lab I was running was able to buy it with safety equipment funding, and it's barely over $400.

A saw like this is the 'right tool' no matter how you cut it. *rimshot*

[sanddrag]

We have a Grizzly horizontal bandsaw, a Dewalt 12" miter saw, and a Rage Evolution saw. The Dewalt is by far the go-to saw for precise cuts in box tubing. With a 72 tooth carbide tipped blade and a careful operator, it makes very nice, very precise cuts, with no real danger involved. You just have to go slow and not cut small pieces. I've even cut small pieces at odd angles with care and caution, and I've even cut 2" solid bar stock on it.

For bar stock, the horizontal bandsaw is our go-to machine. We run a Starret bi-metal blade, and put on a flood coolant system. These two improvements have made a night and day difference. Also, we put on a new 1/2 HP NEMA 56 frame motor. The original caught fire (actual flames) when we stalled the blade in some stock.

The Rage saw is great for steel box tubing, and I'll use it to cut aluminum flat bar now and then. But, it doesn't dry cut without clogging, and the vise is junky and hard to get square. It's good for quick rough cuts with a shot of Kool Mist or WD40.

I just haven't been able to justify the cost of a $1000+ cold saw yet. Anyone have an inexpensive one they're happy with?

[Steven Smith]

Having used both, I think that given the option, the horizontal bandsaws would be safer. Simply put, the bandsaw is going to have less loading per tooth than a circular blade, and the potential for an accident is lessened.

However, a chop saw with a properly clamped piece, where the blade only engages it such that the cutting force keeps the piece pressed DOWN, can be perfectly safe. We had an incident this year where someone attempted to use the radial arm function of the saw, with a churro in the back, and brought the saw from out to in, such that the cut lifted the churro. This bounced around inside the blade guard before hitting the ceiling. A second incident is where I built a wood jig to hold pieces, and I didn't have quite enough downforce clamping for where the piece was relative to the blade, and it pulled the aluminum through a piece of 3/4" plywood jigging making a sound like a gunshot, and tossing the piece. Fortunately, safety glasses policies and no hands near the blade made this a near miss, but a sobering one.

For any harder metals (steel axle rods), the chop saw might also have issues, where a bandsaw would not really care, it would just cut more slowly.

So, I don't think its fair to say "you shouldn't use a chopsaw" because they are dangerous. You just need to be aware that the damage potential is greater, and mitigate the risk appropriately. If you have less strict control over the tools, and see a risk of a student (or mentor) improperly using the chopsaw on metal, you might consider a safer (albeit more expensive or less precise) method of making cuts.

Steven

[techhelpbb]

Per my previous post:

http://www.evolutionpowertools.com/us/build/rage3.php
http://www.evolutionpowertools.com/u...n_build_us.pdf

After a go round with my Rigid saw this was what I bought.
The cuts are cleaner and obviously more thought toward cutting metal was put into it. A 4x more expensive cold saw would be even better and is my tool of choice but for a little late night tinkering this works for me.

Some of the Dewalt saws run at no load RPM near this.
Many of the cheaper saws run at higher RPM.

My other saw is a Harbor Freight bandsaw with a custom down feed system I made. There are instructions for this downfeed elsewhere on the Internet. I recommend this attachment it improves the quality of the cut and the aggravation of using the saw quite a bit.

[magnets]

Originally Posted by fox46

lol alright then, have fun guys.

For those interested in doing things the right way, two options for properly cutting structural tube for less than $400:
[/url]

There's absolutely nothing wrong with using an blade for aluminum in a chop saw designed to cut aluminum to cut aluminum.

If you clamp the part well (not the crappy little clamps that come with saw, something real strong) and don't go crazy fast through the part, you'll be just fine.

[AdamHeard]

It's interesting to see a lot of us have converged on essentially using the same saw. A 14" blade saw designed for metal with the proper blade.

We're loving ours so far, it's a huge time saver during season.

[Steven Smith]

Yep. I think I'm going to try to work one into the budget. Our ~$600 sliding radial arm saw is roughly equivalent (purchased by our teacher before we joined), but the clamping is insufficient and the sliding action is a safety nightmare if used on metal. Thanks for pointing me to the better version of a metal chop saw.

Steven

[geomapguy]

Originally Posted by AdamHeard

It's interesting to see a lot of us have converged on essentially using the same saw. A 14" blade saw designed for metal with the proper blade.

We're loving ours so far, it's a huge time saver during season.

Yep the aluminum blades work like a charm