View Full Version : DIY Cold Saw for Aluminum?

01-08-2009, 02:50 PM
I have a very small shop and have wanted something that cuts cleaner and more quietly than my HF portable bandsaw. I've cut aluminum on miter/table saws before using carbide blades, which got me to wondering about the feasibility of building a "cold saw" using a similar blade, solely for small-ish aluminum.

My thinking was to use a reduction drive to get RPM down nice and low, and have a motor driving a fine-pitch lead screw to control the feed rate. The idea would be to feed slow and steady to keep load manageable. I'm relatively unconcerned about cutting speed. If I could handle up to say a 3" round I'd be delighted, and most of my stuff has a smaller cross-section.

Thinking about it, the obvious issues seem to be figuring out the right type of bearings to support the blade rigidly, and the reduction drive. Given the reduction a worm seems obvious, but not sure how chunky a gear I'd need. It seems like all the force from the cutting tip at the end of a 10" blade would be getting sent right to the faces of the worm gears. It might be easier/cheaper to use some other type of system like ordinary spur gears or belts.

Any thoughts? Too nutty to be likely to work?

01-08-2009, 05:16 PM
im not sure if you would want to use something solid like a leadscrew for the feed. i think something like a spring would work better.

i also think that a worm gear drve would give you too low a speed, i think maybe just a belt drive reduction should be good enough. but then im also no expert and i have not built anything like that before.

noah katz
01-08-2009, 09:48 PM
How about start with the business end of a metal cutting bandsaw; mount the blade where the drive wheel is.

Or for that matter modify the drive wheel to be the blade arbor.

How fast do cold saws turn?

01-08-2009, 10:37 PM
Not nutty at all. We use a milwaukee circular saw at work to cut anything from 1/8 to 1/2 alum. plate. It makes a hell of a racket though. Slower would be better. We also use a spray bottle of WD40.

01-08-2009, 10:40 PM
My thinking was to use a reduction drive to get RPM down nice and low, and have a motor driving a fine-pitch lead screw to control the feed rate.

The metal-cutting circular saws like the Milwaukee are nothing more than a worm-drive circular saw with a carbide metal-cutting blade like the one's from Morse. I've heard they work great for aluminum.

01-08-2009, 10:52 PM
A decent quality miter saw fitted with a carbide aluminum cutting blade and blade stabilizers works amazingly well.

01-09-2009, 01:08 AM
A decent quality miter saw fitted with a carbide aluminum cutting blade and blade stabilizers works amazingly well.

I've used one and liked it well enough but want something quieter. I have a basement shop in a small apartment building, and basically can't run the bandsaw past 9pm if the ground-floor tenant is home. The mill and lathe are OK as they're no louder than the furnace, but the bandsaw makes a real racket.

01-09-2009, 01:18 AM
Sounds like my radial arm saw, in addition to being used as a surface grinder, has potential as a dry saw. I'll have to give that a try. Wonder what a reasonable DOC would be?

01-09-2009, 01:27 AM
I have a DeWalt cold saw, the blade turns at 1300RPM. I've also cut 1 1/2" 6061 on my table saw with a non-ferrous blade in a single pass. Neither one is quiet :rolleyes:


01-09-2009, 01:31 AM
The low speed cold saws that I have used before have always been louder than you would have thought, they seem to gwowl through the stock, especially through hollow stock. Bandsaws always seemed quieter to me.

01-09-2009, 03:30 PM
Hmmm.... maybe need to think of ways to quiet down the bandsaw instead. Most of the noise seems to be from the motor. This is one of the HF portables, not the 4x6. Space is kind of tight.

noah katz
01-09-2009, 04:15 PM
Why the motor?

On mine it's from the sheet metal structure,the stock itself, and maybe the blade singing.

01-09-2009, 04:45 PM
Just a sense based on my ear... It makes 95% as much noise running in air as cutting, so it's not the stock (unless it's something musical like an extrusion). I'll take the blade off and run it and that should isolate further. Maybe it's the motor and reduction gear together, or the gear more than the motor.

01-09-2009, 08:50 PM
The motor is a universal series wound motor. Just like a hand drill or a blender. Run fast and are geared.

Best solution is to either get a bandsaw. a 4x6 is good or look at a 14" vertical delta. A wood cutting bandsaw cuts aluminum great. They can be found on craigslist cheap.

01-10-2009, 08:59 AM
I use an import copy of a 14" vertical Delta for wood and aluminum. Per a tip somewhere I sprayed automotive undercoat on the inside of the sheet metal housings/guards. Seems quieter to me.

01-10-2009, 06:13 PM
Maybe a sound proof booth to do your cutting in, and a white noise generator to mask whatever sound does escapes the booth?

01-11-2009, 12:46 AM
I believe the bandsaw is going to be the quietest way to cut materials. The specific one you have is probably beyond trying to modify to quiet it. I'm with the 4x6 camp- a decent one of these can be modified in a few ways to make it quieter, but they aren't too bad as is. I say a 'decent' one'- it would pay to be able to check out a few to weed out the garbage.

A few of the mods I've done to mine - played with the blade cover so it wouldn't vibrate, put a link belt in place of the original (much nicer now) , did some work in the blade guide area to improve tracking, worked on the pivot point of the angleable fixed vice jaw to improve accuracy, and replaced the tin table which is used in vertical operations with a thicker piece. This part, the replacement table, is sized much smaller than the original since I don't remove it when horizontal cutting. It has to clear the bed to allow the blade to drop all the way through a cut. At any rate, it's not nearly as bad a 'sounding board' as the original. Always use good blades- the one that comes with it is probably crap.

The metal cutting 4x6 is one of the machines I couldn't be without now.

01-11-2009, 02:56 PM
Cold saws for steel are slow.
Cold saws for aluminum are VERY fast.
You dont need to slow down for aluminum, you need to speed up.
A regular skil saw will work for aluminum, but in reality, its way to slow to be most efficient.

Pistorius and others make cold saws for aluminum- speeds are usually around 3000 rpm or higher.

But they are noisy buggers.