can i use a wood band saw to cut metal?

hey bonzai, i just bought one and cant get the SOB to cut for shit. i keep throwing the blade. got any hints?

 

Had to bring this one back up. Has anyone tried a rheostat or some other kinda switch? Ceiling fans, wash machines, etc, all have multiple speeds.

 

Nobodies tried to use a switch to slow it down?

 

I just got one of those. It used to belong to my father-in-law; he hardly used it. The problem is, it also keeps throwing the blade. Any ideas on how to keep this from happening?

 

That is the same saw I just picked up from Brad54.

Basically I figured out from the 1725 RPM motor, the 2.5" drive pulley and the 5" driven pully and 12" band saw wheel - the blade was running 2747 FPM

From Digger Dave's post, I set up the equation aiming for 300 FPM and found that I need my 12" band sw wheel turning at 95 RPMs - with the current pulley configuration of 2.5 drive and 5 driven it is running at 875 RPM.

36-2 Window is correct in that you will need a serious reduction. Simply chaning pulley would require around a 12" diven pulley on the back. Something tells me that isn't going to fit under the table.

I went and found a 19:1 parallel shaft speed reducer on Ebay - for 80 bucks. This was a good deal - it sells for 375 at grainger. I suddenly found out speed reducers ain't cheap.

Anyway, I am going to attach that to the motor shaft and put a new 4.75" pulley for the drive pulley - 6 bucks. With the origianl 5" driven - From 1725 RPM motor / 19= 90 RPM Driving RPM which tranlates to about 85.5 rpm on the 12" driven band saw wheel - which will give me around 268 FPM at my blade speed.

Does anyone know when 268 FPM is too fast? I see some metal band saws you can purhcase have Variable Drives that allow the user to go from 150 - 350 FPM. I also confirmed the metal saws come with rubber on their saw wheels. I was sort of worried the metal saw wheels didn't have the rubber on them. I thought the metal shavings may screw them up.

What is the theory for the different speeds? I am mainly going to cut plain old steel and maybe some aluminum.

I purchased a bi-metal variable pitched 1/4" blade - it seemed to be the most versitile.

I'll get some pictres.

 

If your not cutting much it's cheap to ask a fabrication shop to cut out what you want. look up metal dealers, welding, and fabrication shops and call around.

For brackets and small stuff......I can cut 3/8 and 1/4 inch with my hand held dewalt jigsaw and a bi-metal blade. My jigsaw has a variable speed and the slowest speed works great. It cuts faster than you think it will. Wear a face shield! .. hot metal fragments in your eyes is not condusive to good eye-sight.

 

Now that's funny.

 

I use mine for all my 18 guage and thinner small pieces. Works great with a metal blade.

 

I bought a 16" Rockwell vertical bandsaw on ebay for $180.00...should last longer than me....

 

my electrition said that it'd burn the motor up when i asked him about doing that to another tool.....he said that it'd need to have a dual power source or some shit like that.

 

i use wood blades for cutting thick aluminum at the standard speed. any thing thinner then 3/16 i need to go to a finner tooth blade.

 

The October 1993 issue of American Rodder has a really good article showing a really easy way to convert a wood cutting bandsaw for use with both wood and metal. It basically entails a double-sheave 2 1/2" pulley on the motor that turns a 14" pulley that is connected to a jackshaft. The motor drive and the 14" pulley are on one side of the machine with the pulleys sticking out of the side. A small guard was used to cover the exposed pulleys. On the other side of the jackshaft was another 2 1/2" pulley that ran up to the main drive pulley. Pretty simple actually. The reason for the double-sheave pulley on the motor is to allow the machine to function as at wood cutting speeds also. The second sheave on the motor pulley drives a 2 1/2" single-sheave pulley that is right next to the 14" pulley. By switching the belt between the two sets of pulleys, you have both functions.

Chris

 

On the HF bandsaw, the blade guides need to be adjusted. Those rollers that the blade goes through. They are never adjusted right from the factory.The pins the rollers are mounted on are ecentric, and you turn them to adjust them. Loosen the nut, and turn the pin with a thin wrench. They have to be set tight enough the blade is held straight, but not so tight the blade is pinched between the rollers. Set the inside roller first, so it holds the blade straight, the put a piece of paper between the outer roller and the blade, and adjust the outer roller so it will just hold the paper in place. Try it and see how it works, more adjustment may be needed. I have set up several saws like this, and they work fine for a long time. I have been using the one I have now for over 10 years, and it still cuts like new.

 

I got my saw converted this weekend - IT WORKS SWEET. I am turning my 12" wheels @ 88 RPM that translates to like 275 FPM. I put 1/4" variable tooth bi metal blade on it too.

It is a hell of a lot better that cutting everything with ziz wheels. I am anxious to see what I can do with cutting some curves too.

Good luck fellas

 

It also helps to add some oil while you're cutting... especially with thicker stuff. Motor Oil, WD-40, etc. will go a long way to making the cut go faster while increasing the life of the blade. (Works for sawzalls, hole saws, drills, etc. as well.)

 

Limiting the current passing through the motor will indeed lower the RPM's, but it is not the same effect as "gearing down" and increasing torque.

 

Thanks slide - my buddy who does a lot of machining was telling me about "cool tool" lubricant? said it worked better than the motor oil. He also said wd-40 wasn't the best thing to use although it would work. Not sure why.

AC motors need to be constant speed with the correct voltage going to them If you want to vary the speed with voltage - DC motors with a variable speed drive are the ticket. Think slot cars - and the little controlers.

 

At the sign shop years ago we would cut out aluminum letters for the neon cans and would gear the wood saw down and use a metal blade with plenty of bee's wax to lubricate it.

Another trick, when cutting sheet aluminum was to turn around the carbide blade on the table saw and wax it up with bee's wax.

 

I won't be cutting much alum I don't think - you gotta go faster than steel right?? how much faster???

To use the wax - just stick it on the running blade to coat, then cut the steel???

 

Tudor - I dont remember the speed of the saw but I do remember setting it on the slowest speed available with the pulley combinations. Someone always bitched that it was too slow when they had some wood letters to cut.

We would bump the saw on and then off to get it moving and then hit it with the bee's wax on the sides of the blade. On the table saw for cutting thick stuff we would set the blade high and let it rip, if it was thick we would use wax on the aluminum itself too, but watch that it didn't get too hot.

I picked up a aluminum blade for my miter saw to cut hurricane panel mount channels and shower enclosures the blade is like $60 - $80 from a company CR Lawrence in SC.

 

wilton tradesman 14" wood- metal cutting band saw amazon .com around 845.00 plus shipping.or make up a jackshaft set-up which is what im trying to find out about before i buy another saw.

 

if you are talking about a 4x6 i bought a jet awhile back and was having the same blade problem i found that increasing the blade tension stop the blade from coming off at least on mine.

 

Here's the hot ticket....use a motor and variable speed switch out of a good size treadmill. They have DC motors with a speed switch. my friend has one on his wood saw with a metal blade. has plenty of power and he can slow the blade down so slow you can count the teeth on the blade

 

I set on up like one I had seen on an auction years ago. I have 2 motors on it. The upper one drives it for wood cutting and acts as a jackshaft with belt pulley speed reduction when I use the lower motor for metal cutting. Works great and I use it all the time.

 

This sounds like a a good tech post. Could you get your buddy to write up something and post so pics?

Tucker

 

I will see about that.
If you have been on a treadmill, most I have been on have a knob that you turn to either speed up or slow down the belt.

The belt you walk on is driven by an electric motor. This motor will bolt right up in the same location on your wood saw as the present one that turns too fast.

The whole idea is really simple. Wish I would have thought of it.

You unbolt the electric motor you currently have on your wood saw. Replace it with the motor from the treadmill. The motor on the treadmill will have a pigtail of wires that go to the knob on the console panel that controls the speed of the belt you walk on.

After you mount the treadmill motor, route the pigtail of wires and the knob to an easy to reach place on your saw.

The secret is to make sure the treadmill motor you get is from one of the larger treadmills, or at least the same HP rating as what you currently have. I wouldn't go under a 1/2 HP rating.

Go cruising subdivisions on trash day or the day before, and you can probably find one setting out for the trash man.

 

I have just looked into this as well. I have a Atlas bandsaw and the blade speed is about 3000 fpm, which is a shaft speed of about 865 rpm. If you run thin metal through the saw, properly outfitted with a metal cutting blade, you can get away with it. Any thick material and you just burn blades up. According to the Do All and Grob saw charts, quality steel plate needs to be cut at about 100 fpm to keep blade wear to a minimum. and yes a 2 to 10 to 2 to 10 inch double pulley system will work, but I bought that Gorb mulit speed saw (50 to 3000 fpm) for $150 plus the price of a phase converter at $175.

I am sure there are other ways and plenty of good advice already given.

 

I would use a grinder or metal cutting disk, if you do have to use a saw use lubrication on the part like gear oil.

 

I have seen this done using an old 5 speed manual transmission from a car as a speed reducer. the nice thing about that, is that with a metal cutting blade, in low gear, you can cut metal very well, and if you do want to cut wood, you shut the motor off, shift the tranny into a higher gear, and the metal cutting blade will do a respectable job of cutting wood, at the higher speeds.

 

tredmill motors are all DC that i have seen, i have a couple here now but the rectafiers are toast, guess thats why they free, but if you can find one with a good rectafier then you should be able to use one on a bandsaw.