I dont do alot of fabrication at home but enough that I wanted something a little bit easier and not as loud as a cutoff wheel or grinder. I always wanted a metal cutting bandsaw but they are expensive except the little HF ones. I also wanted to be able to cut other things as well like wood or foam or whatever. So I kept my eye out and got an old Rockwell vertical bandsaw locally for 50 bucks!
It was in good shape and worked, its not the oldest style with a beefier frame but it will do what I need.
Now I heard that you could use a treadmill motor and variable speed drive that comes on them to convert a wood bandsaw to go slow enough for metal. I found a 1.5HP 90VDC motor , transformer and variable speed controller from a treadmill on Epay for 50 bucks! You could probably troll garage sales and get one for next to nothing.
The old 1/3hp AC motor just mounts on a pivoting plate under the saw. I took it off and the DC motor bolted right in. It even had the right size pulley on it.
You can see a little set screw on the pulley. You can adjust the pulley about 2 inches on the shaft to line up with your saws pully where you need it.
Now this controller was small enough to mount in a regular handy box from a hardware store. I got a blank cover for it to mount the speed control (potentiometer) in. The card has L1 and L2 pins on it. this is where you hook up the 120VAC. I got an 8 foot pigtail from the same hardware store and a 1/2inch compression fitting for the handy box to put the cord in. Now there are 2 more pins on the card that say A1 and A2, this is where the DC motor hooks into. But you have to have 1 of the DC motor wires go through the transformer before it plugs into the card. I think it can be either one because I tried it both ways and it worked. Now the 2 wires can go to A1 and A2. To make the motor go CW or CCW just switch the A1 and A2 wires. I ran the 8 foot pigtail and the 2 DC motor wires through the 1/2 inch comprssion fitting and into the handy box. I grounded the pigtail ground wire to one of the screws that I used to mount the box to the saw leg.
The transformer I mounted on the saw leg across from the handy box. Now the DC motor also has a ground wire and I ground that wire to one of the screws I used to mount the transformer.
Here is the handy box mounted with the speed control mounted on the cover. The DC motor has what I think is a small balancer and fan on this end. I think I will take off the fan but leave the balancer. I will make a guard for this end of the motor.
Here is the finished saw! (except for the guard) It doesn't look much different than it did.
When you plug it in the motor doesn't even move till you turn the dial a little bit. You can go from 0 to 4800 RPM!! A DC motor has the about the same torque at any RPM so you can slow down to do metal (with a metal blade). I put on a blade that had about 14 teeth per inch and it went right through this 1/8 x 1 1/2bar.
If I pushed real hard I could bog down the motor but I just let the blade do the job and it went through real nice. If I was converting a full size wood saw I would probably use a bigger HP DC motor. Any way good luck on your project!
It was in good shape and worked, its not the oldest style with a beefier frame but it will do what I need.
Now I heard that you could use a treadmill motor and variable speed drive that comes on them to convert a wood bandsaw to go slow enough for metal. I found a 1.5HP 90VDC motor , transformer and variable speed controller from a treadmill on Epay for 50 bucks! You could probably troll garage sales and get one for next to nothing.
The old 1/3hp AC motor just mounts on a pivoting plate under the saw. I took it off and the DC motor bolted right in. It even had the right size pulley on it.
You can see a little set screw on the pulley. You can adjust the pulley about 2 inches on the shaft to line up with your saws pully where you need it.
Now this controller was small enough to mount in a regular handy box from a hardware store. I got a blank cover for it to mount the speed control (potentiometer) in. The card has L1 and L2 pins on it. this is where you hook up the 120VAC. I got an 8 foot pigtail from the same hardware store and a 1/2inch compression fitting for the handy box to put the cord in. Now there are 2 more pins on the card that say A1 and A2, this is where the DC motor hooks into. But you have to have 1 of the DC motor wires go through the transformer before it plugs into the card. I think it can be either one because I tried it both ways and it worked. Now the 2 wires can go to A1 and A2. To make the motor go CW or CCW just switch the A1 and A2 wires. I ran the 8 foot pigtail and the 2 DC motor wires through the 1/2 inch comprssion fitting and into the handy box. I grounded the pigtail ground wire to one of the screws that I used to mount the box to the saw leg.
The transformer I mounted on the saw leg across from the handy box. Now the DC motor also has a ground wire and I ground that wire to one of the screws I used to mount the transformer.
Here is the handy box mounted with the speed control mounted on the cover. The DC motor has what I think is a small balancer and fan on this end. I think I will take off the fan but leave the balancer. I will make a guard for this end of the motor.
Here is the finished saw! (except for the guard) It doesn't look much different than it did.
When you plug it in the motor doesn't even move till you turn the dial a little bit. You can go from 0 to 4800 RPM!! A DC motor has the about the same torque at any RPM so you can slow down to do metal (with a metal blade). I put on a blade that had about 14 teeth per inch and it went right through this 1/8 x 1 1/2bar.
If I pushed real hard I could bog down the motor but I just let the blade do the job and it went through real nice. If I was converting a full size wood saw I would probably use a bigger HP DC motor. Any way good luck on your project!
