band saw speed for metal?

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Sure, I'm aware of that but your cutting speed seems really low? I thought it was like 250?
"A1008-A1013 cold rolled sheet: 250 (sfpm) blade speed 8-10 (sipm) cutting speed"
Im cutting up to 1/4 and down to 16g, but 1/8 is what I expect to cut the most of. With this setup I should be able to get it pretty low. Nice thing about DC is you dont lose torque down low, think Tesla. You can rip through thin AL it a pretty fast rate.
 
i get 125-215 sfm for 1008 steel. by the time you get down to 16 gauge, you are probably better off with a shear or abrasive wheel. too thin is hard on bandsaw blades

AC vs DC wont affect the torque. that is mostly a function of motor design. Tesla uses 3 phase SCIMs which are 3 phase AC, not DC. Universal motors like a treadmill are series wound brushed DC motors with some design changes to work better on AC.
 
This motor seems to be brushed DC as I can measure the DC in 'voltage' off the controller board. 10V is about 600 RPM, 90V is screaming. The flywheel is about the mass of an LA damper and has the same balance type holes. I put a small magnet in one of the balance holes (fit perfectly) to see if I could get the distance function to work but even the small magnet threw the balance off enough to make the motor start to bounce in my vice. Pretty good factory balance on that flywheel. Ill have to rig up a hall effect sensor (old Cam sensor I still have) to pick up the balance hole or the fan vanes on the rear for some sort of RPM monitoring or maybe a reflective tach measurement compared to the 'speed' (in MPH of the conveyor belt) readout. Going to get that Ford ribbed crank pulley today from waste bin at work, hope its still there. That would give me about a 5:1 reduction to the bandsaw input shaft. Im shooting for ~70 RPM of the 12" wheels @ ~220 FPM...Damn that seems slow for a saw......
 
for a reference, look up a video of a small portaband. they seem slow bit they work really well
 
for a reference, look up a video of a small portaband. they seem slow bit they work really well
I worked with one a while ago, cut a 5" pipe no prob but it took about 10 minutes. Ill get something going. This motor control is cool, if it bogs down it will ramp back up to speed under load. Wonder how it will function as the bandsaw starts to load up. I wonder why they don't make drill presses with this type of motor? Infinite speed control for 1/4 bits to hole saws.
 
I worked with one a while ago, cut a 5" pipe no prob but it took about 10 minutes. Ill get something going. This motor control is cool, if it bogs down it will ramp back up to speed under load. Wonder how it will function as the bandsaw starts to load up. I wonder why they don't make drill presses with this type of motor? Infinite speed control for 1/4 bits to hole saws.
the problem is that they dont have a maximum speed. with no load you either need to turn down the voltage which causes heat, or they speed up until something fails. many good milldrills have a 3 phase motor and a small VFD now. cheap drill presses are cheap and they are not going to spend extra redesigning them. VFDs are getting cheaper and 3 phase motors only have bearings to wear out. the belt grinder for knife making at my space is a shop made tool, the only parts we had to buy were the pulleys and the VFD. its a couple hundred bucks all in and has lasted for atleast 6 years, other than bearings wearing out. the motor and frame parts were all free/junk.
 
Here is the VFD paperwork that came with my unit that is a AT1, if you look they make a AT2 that is single phase to single phase.

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interesting, my 2.5HP single phase has 220 wiring option. Thanks!
 
Here's the guts of the treadmill

Wow, you're short!
Great ideas here.. have you thought of a lube system?
Ebag has some inexpensive air/water kits cheap
 
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