MetalworkingFun Forum

Need to build a disc sander?

This will do the job.

http://www.youtube.com/watch?v=qSy3rE-yRP8

Love to have a few of those discs in stock for projects!!

That video is a little deceptive because it's not done in realtime, although they did show the elapsed time clock running. I've run big Marvel vertical bandsaws back in the 1980's which could also cut clean and stright like that (within .010" flatness in 12" rounds) when a new blade was properly aligned and tensioned.

FWIW, I have a bandsaw website bookmarked on my PC because they've got some great prices on bandsaw blades and other goodies. Well worth a look!

http://bandsawparts.com/index.cfm

Thanks, Wow, lots of reference there, Thanks for that!!

Built a disk sander close to that size. They're cutting 18 inch disks, mine is only 16. Made it from plate though. had the disk faced and back faced, (before I had a lathe big enough), look at the holes I had to drill to balance it.

I didn't appreciate the size of that round stock until I saw the guy measuring the thickness!

Nice work Greg. What is the ?screw for in front of the column?

Greg, is that a 1725 motor?

Disc sanders are a great shop tool, do a great job. Nice stand.

I was still building in the last photo, had thought about using that screw to raise and lower the table but left it out to save time. I don't adjust the height often but the table assembly is heavy.
Yep 1725 motor, the smaller disk at the back it the rear disk off a chev pickup, thinned down to work with a snow mobile disk caliper. It will coast for about 5 minutes without it, the small switch is for reversing the motor, you need to stop it first.

One of my grinders, like my Delta mitre saw, employs electric braking by dumping the power generated by the run windings into some kind of resistance. Really slows down the "coast to stop" time. But admittedly a truck disc brake would stop even faster. ( was gonna say "would slow faster" but that seemed a bit contradictory.)

Can you employ motor braking on an AC motor? My makita miter saw uses it too, but they're brushed motors. Inquiring minds need to know.

At work ( back in my days of employment) we had a dynamic brake installed on a drill press. It was a little more complex and fairly expensive but it was the same brushless AC motor that was originally on the DP.
My Busy Bee grinder isn't a brush motor and once the motor slows below what I figure is the speed the start/run centrifugal switch de-activates it changes sound and there is definitely a rapid deceleration. Maybe when the switch re-connects the start winding it has a braking action.