Converting a wood bandsaw to metal bandsaw

[fatal-exception]

I know that most of you will say don't do it, but I rarely ever work with wood anymore and was wondering if anyone out that has done this? I have a 16" bandsaw that has a 3/4HP motor. It is entirely cast iron other than the guards.

The problems I see are:
Rubber wheels for driving the blade
Lack of coolant system
Blade speed too fast

I don't think rigidity will be a problem. This thing is well built.

I guess the big one is the rubber wheels. I've never looked at how the rubber is attached to the wheels, but would it be possible to remove the rubber and run the blade directly on the aluminum? Could I just leave them alone and use them the way they are?

I can buy a mist coolant system for it, so I don't really see that being a problem.

I can change the ratio from the motor to the lower wheel pretty easily. It's just a standard V-Belt system. Maybe I can implement a step pulley and tensioning system like a drill press to adjust the speed for different materials.

So what do you guys think?

Paul

[CalG]

Three phase motor and a VFD
My old Oliver cuts anything now!

(Just not too fast if the metal is thick ;-))

[packrat]

Leave the rubber on the wheels. As far as coolant if your just doing contour sawing, you usually don't need/want it. So you can see the line your cutting.

For most stuff I do, around 100-150 SFM(surface feet minute), works. Measure your drive wheel diameter and motor speed and go from there to figure your pulley needs.

Good luck, cary

[ninefinger]

Just change the speed. I have a 3 wheel Delta 16" bandsaw that has "rubber" on the wheels and its not a problem. Just be sure to buy some good metal cutting blades. Starrett make some great ones.

For the occasional cut of thick steel I have a hand held sprayer that I use and I squirt a little coolant once in a while - seems to help keep the teeth from clogging up.

Mike

[BobWarfield]

Like the peeps said, leave the rubber wheels. I've got a Rockwell Delta 20" metal cutting bandsaw and it has rubber wheels.

You are going to want to change the pulley ratios to get the speed way down as was mentioned. Perhaps a VFD too. A 3/4 HP VFD is not too much money, but I'd try to get in the right ballpark with a pulley change and then go VFD to fine tune it to keep the torque up.

BTW, the Harbor Freight blade welder is cheap and works fine. Blades are a lot cheaper if you weld them yourself and it isn't hard to do.

Cheers,

BW

[packrat]

An alternative way to lower your speed is to get a speed reducer gearbox. Using just pulleys you usually need to do it in compound, to get it slow enough.

Another way I've seen people do, is to use a transmission from an old lawn tractor.

cary

[fatal-exception]

Thanks for all the tips. Yeah, I see that I will need between 30 and 50 rpm at the drive wheel. Yikes, that's at least double reduction. I like the VFD idea, but don't really want to spend the money, besides I would then need to get a 3ph motor too.

I'll try to design a jackshaft system first, if I can't make it fit in the space under the saw, I will go for the VFD.

Paul

[BobWarfield]

I think a surplus speed reducer gearbox is probably the cheapest and easiest way to get there.

I hear what you are saying on the cost of VFD and 3ph motor (BTW, I think you'd still want a speed reducer gearbox with that combo). However, look at what 16" metal cutting bandsaws cost and it's a bargain even so.

I love my Rockwell Delta 20". It goes through metal like a butter and lets me bandsaw things to save milling time.

Cheers,

BW