Bandsaw motor upgrade question?

[mbolt512]

My bandsaw has a 3/4hp motor at 1725 rpm and I want to upgrade to a 2hp. My question is do I have to get a 2hp at 1725 rpm's or can I get a less expensive 2hp at 3450 rpm's and then use a different size pulley to get the 1725 rpm output. If so, what's the pro's and con's of the less expensive, higher rpm motor. My drive pulley is 1.625", so I would have to change my output pulley from 5.125" to a 10.75" to get the rpm's back in line with the original setup. Any help would be greatly appreciated.:icon_scra

 

[MrAudio815]

Not sure, but I think my G0514 BS runs at 3000+ RPM's.

I know it has a slower setting at around 1700 RPM's and was told the slower speed is more likely for metal, but 1700 is still too fast.

Look up Grizzly's BS and see what there RPM ratings are.

 

[Gotcha6]

It may not be as simple as that. Imagine puttin' a hemi in a Cooper Mini.:gar-La;
First off, is the shafting on the bandsaw heavy enough for the additional torque. After all, with the same rpm motor you are going to increase the torque to the shaft by a factor of almost 3.
Secondly, is the bandsaw frame heavy enough to take any additional loading from using this extra power. If you start to doing resawing and pushing massive boards through the blade will it take the strain?
Thirdly, how's the tires? Forty gazillion horsepower on a car ain't no good if ya can't get it to the ground. If the tires don't get the power to the blade it'll start slipping. Burnouts are great in Oakboro, NC on Saturday nights, but it makes for bad sawing.
Thirdly, how's the belting? You may want to look at a double sheave pulley to get all that power to the saw.
JMTCW
Good luck.

 

[Alan in Little Washington]

I did it (see this thread). Barely had enough room for the new motor, but everything else was fine. After that thread was written I adjusted the position of the pulleys and was able to fit the motor inside the existing cabinet. You may have a hard time finding a 10.25" pulley that won't cause vibration at a reasonable price.

 

[eyekode]

I did it (see this thread). Barely had enough room for the new motor, but everything else was fine. After that thread was written I adjusted the position of the pulleys and was able to fit the motor inside the existing cabinet. You may have a hard time finding a 10.25" pulley that won't cause vibration at a reasonable price.

Alan, I didn't notice in your thread about RPM. Your new motor was the same RPM right?

I looked into doing this as well as I had a nice 1.5HP motor sitting around but the pullys would kill the deal. Too expensive and too big.

Salem

 

[Alan in Little Washington]

Alan, I didn't notice in your thread about RPM. Your new motor was the same RPM right?

I looked into doing this as well as I had a nice 1.5HP motor sitting around but the pullys would kill the deal. Too expensive and too big.

Salem

Motors were same RPM. Shafts were different size, so I got a new machined motor pulley from McMaster-Carr.

 

[mbolt512]

Alan--This is the pulley I was thinking of using (http://www.thebigbearingstore.com/servlet/the-988/10.75"-A-Belt-Industrial/Detail). I don't know if it's any good or not but, it's the only one I've found so far that will work.

 

[Alan in Little Washington]

Alan--This is the pulley I was thinking of using (http://www.thebigbearingstore.com/servlet/the-988/10.75"-A-Belt-Industrial/Detail). I don't know if it's any good or not but, it's the only one I've found so far that will work.

That should work. If it is out of round, a machine shop can mill it true.

 

[DIYGUY]

My bandsaw has a 3/4hp motor at 1725 rpm and I want to upgrade to a 2hp. My question is do I have to get a 2hp at 1725 rpm's or can I get a less expensive 2hp at 3450 rpm's and then use a different size pulley to get the 1725 rpm output. If so, what's the pro's and con's of the less expensive, higher rpm motor. My drive pulley is 1.625", so I would have to change my output pulley from 5.125" to a 10.75" to get the rpm's back in line with the original setup. Any help would be greatly appreciated.:icon_scra

Are you on a 240VAC circuit? Many motors out there claim to be 2HP (or absurdly higher - think ShopVacs). These ratings are PEAK HP only and are not to be confused with running HP. The higher the Voltage the lower the Amp draw needs to be to obtain equivalent shaft output. That means that when loads increase and current draw rises your motor does not have to work nearly as hard to achieve the desired results. If you are on a 120VAC circuit you cannot achieve a true 2HP no matter what the motor states. About the *best* you will get is something near 1HP not 1.5HP, and most definitely not 2HP. So if you have a dual voltage motor try bumping it up to 240VAC first, then see if you need a new motor.

I am going to assume that you are on a 240VAC feed. The higher HP may help you, it may not. You might get the same result. You should get a better understanding of what torque is all about. You might actually be able to obtain the desired result with a simple swap of your pulley.

Take a look at my post here: http://www.ncwoodworker.net/forums/f19/variable-speed-control-question-1hp-24459/

Best of luck with whatever path you take ...