Converting a Bandsaw from Wood to Metal TECH!

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 1/2 steel bar.

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!

 

shweet....I've been thinkin bout this for awhile but was unsure of the route to go....thanks for clearing that up for the electrically impaired

 

I saw one of these at a garage sale today i think it might still be there. I guess i need to go back.

 

thanks a lot for the tech article. I found a saw on craigslist that I was thinking about getting buy was unsure if it would work on steel. Now I know what I have to do.

Thanks a lot, this site is the best

 

It was real easy and only took a couple hours. If you take apart a treadmill take note on what wires go where in case the card is printed different.

 

i think the ballsac cooling fan is the coolest part. no more sweating your balls off while sawing metal. fuckin aye.

 

I didnt think of that! Ill leave it on!

 

that is soo cool. I just picked up a saw and was wondering what I going to do with it, now I am looking for a treadmill.

 

nice! I recently got an old King-Seeley saw (missing the motor) and someone gave me a treadmill motor.....hmmm....

 

I got the HF metal saw and it really not that bad, especially when its on sale for $120

 

Cool stuff! I'm definitely on the lookout now.

 

Dude! Thats the exact same bandsaw I have! Now I just need to steal the motor outta the wifes treadmill. She wont even know its gone, she never uses it anyway. There has got to be more un-used exercise equipment in this world than fat chicks!

 

We were talking about this today on the way back from the Albany swap meet. My bud Bruce was saying his uncle used an old Triumph transmission to turn down a wood band saw for metal cutting. Great idea I thought.

 

Great TECH!! I will be using this one

 

Great article, I have been wanting to build or buy a metal cutting band saw for a while. One question though, I know its going to sound stupid, but would putting a dimmer switch on the AC motor kill too much torque on the AC motor? I've got a couple of old band saws, and know where I can get a whole treadmill for nothing, but was curious of why you use a DC motor. I see the comment about the torque staying roughly the same at all RPM's, but was just curious. Thanks for the post.

 

I forgot to see if it was still there when we were leaving yesterday. Go get that shit!

 

AWESOME tech. Can't tell ya how many treadmills I see sitting out for the trash man. Thanks for another excuse to start gathering junk. lol.

 

It can be accomplished this way too, but you will have to go to a place that deals in heavy motors and controls to get a variable control for a motor of the HP rating you are trying to adjust the speed on , I think it could also be accomplished by using a bigger pulley , it may not have the torque ,( but not sure about that )

 

Nice tech !! Now watch the prices for old treadmills and bandsaws go thru the roof .

 

Great tech. Ive wondered how to convert wood saws to metal. Cheap DC motors in treadmills..........Never would have figured.

Thanks, ROB

 

Ive think that AC motors like to be going the rpm they are rated at like 1750 rpm. They make AC variable speed drives but they are a lot more than just a dimmer switch and a lot more expensive. DC motors arent rated at a set rpm, they have a range like 0 to 3800 rpm and are meant to work all thru that rpm range.

Also keep in mind that HP ratings for DC motors are not accurate. A 1.5HP DC motor probably puts out about .75 HP because thay arent as efficient as AC motors. So for a bigger bandsaw I would look for a 5 to 7 HP DC motor.

 

found these controllers on Epay that are pretty heavy duty , higher volt and amp range than the one I used. pretty good price too!

http://cgi.ebay.com/NEW-MC-60-Icon-...ryZ15280QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

 

I'll call a buddy of mine tomorrow, and ask him, they do all kinds of tool repair, maybe he has an idea about it as well. Hell maybe he has another old bigger band saw laying around I can get for cheap and do this mod to as well Great tech again, I'll be workin on this, this weekend for sure

 

I Just snagged a not too old but cheesy Crafty Bandsaw from a local pawn shop real cheap since it had been sitting there for 10 months.

My metal conversion plans include slowing down the drive wheel by using a countershaft and additional pulleys, etc. Here are the questions.

1. For light duty metal cutting bandsaws (say 1HP of less), What is a good blade width? 1/4" seems too narrow, what about 3/8" or 1/2" or wider?

2. For general purpose cutting (Aluminum and mild steel to 1/2" thick) what tooth counts are good? 14, 18 or 24 TPI or the combo 14/18 blades?

3. What feed speeds are you running on your coverted bandsaw? I have seen metal cutting bandsaws all over the place from 80 to 500 Feet/ Min.

Thanks, in advance for the help.

N B R

 

Im in the process of getting myself one as well. Good post!

 

This one is variable from 0 to 3800 or so RPM so whatever speed you want!

 

Great post. I was trying to figure out how to do this with different sized pulleys about 6 months ago and came to the conclusion it had to be done electrically. Thanks man, now I dont have to think as much!!!!

 

I got a big meat saw a few months back. I will have to start hunting parts to convert it to a speed control.

 

PLEASE READ THIS POST IF CONVERTING A WOOD BAND SAW TO METAL USE!!!!

Guys, if you do this conversion, please clean it thoroughly of wood dust. I have a buddy that burned his house down because hot metal chips smoldered for a day in saw dust before catching everything on fire!!!! And if you do this conversion it is highly recommended to keep it dedicated to metals.

 

Great now I'll have to pay for my next treadmill .. I've been gathering them up for a while even have one of those DC motors on my old lathe . A landice treadmill has a 3 hp motor - big suckers heavy and tons of tourqe for moving fat asses . I've got some of the treadmill belt rollers I'm gonna build a roll former out of for sheet metal . They would also make a nice big belt sander they already have tracking adjusters built in and really good bearings . Always got good laugh seeing a driveway lined with excersize equipment and work out videos at a garage sale and on the porch sits a sweat hog with a box of doughnuts and a diet coke .