Quote Originally Posted by Make Things View Post
This is great information! The only way I ever 'rip' metal is by using a grinder, like a caveman beating an animal to death with a club. I didn't realize it went beyond woodworking, but, I mean, it's the same set up with more teeth, right?
You do want to slow the bandsaw blade down from the wood working speeds when going to metal with bandsaw blades that are intended for steel. 100 surface Feet per minute (SFPM) being the typical high carbon heat treated blade speed (blades can get expensive with bi-metal HSS cobalt). That may be possible with step pulleys, or intermediary jack shaft. Easiest that I've done is put a 3phase motor on the saw, and drive it with a VFD (variable speed drive) and slow it down to the needed SFPM.

This makes switching back to wood easy. VFDs have gotten very affordable. I've had good luck with used ones off eBay or local Craigs list or FB market place. Just make sure it's a 200 class series (intended for 240V operation, vs the 400 series for 440V operation). I've never had and issue with single phase input creating the needed 3PH output. But there are some that have a phase loss detection on the input. So download the PFD manual for the model you're looking at and check that it can run on single phase. Under 3HP you don't need to derate the VFD, the limiting factor is the input rectifier diodes. Over 3HP, they typically derate to using twice the VFD HP of the motor your driving.

VFDs typically have a programmable display, where you can insert a scaling constant to convert hertz to spindle RPM, or in this case SFPM so you can dial the speed in quick with the potentiometer on the front panel of the VFD.
The other rule of operation, NEVER switch the VFD to motor output connection, as that can blow the VFD transistors up. They really are easy to connect to the motor. And there's many ways to start and stop them, with external switches and such. It's all in their user manuals. If you can't find the PFD of the manual, don't buy it. I've typically only seen that on Rockwell Automation, that seems to delete older models from their web site.