Test driving Nathan's disc

Nick, I'm guessing your Leeson is AC running on a VFD... Are you using the braking feature of the VFD, or do you run this slowly enough that it's not a big deal waiting to let it spool down to reverse it? If you aren't using braking, does the added mass of the steel disc make a noticeable diffference in how long it takes to stop? Seems like it would have lots of flywheel effect, and (again, I'm guessing here) you're reversing the disc to swap to the other side of the blade, no?
 
I have used mine on 8 knives in the last 2 days; I don't notice any difference(aluminum to steel disc) in the braking of the VFD or difference in reversing the disc. I am flattening tapered tangs and cleaning up the flats on blades.
 
A lot of my work is done at slower speeds, flattening and lapping ect, Im using a KBAC VFD, I put a foot switch inline to the fwd/rev switch. I set the speed and you can set the part on the disk, step on the pedal and grind/lap, let off the pedal and remove your part after the plate stops spinning, it stops pretty quick.
If the disc is always spinning, it's be hard to apply and remove a part without messing up an edge or flinging it across the room (especially if using lapping paste).
 
Last edited:
Wait a minute here--- I thought Matt Gregory fell off the face of Mother Earth!?!? :eek: Seriously though, I hope all is well with you and I'm glad to see you post here my friend! :)

I am using a VFD... but for that particular motor, it is not an ideal set up--- that motor is 1hp, 3600 rpm
(I got the motor for $50 since it was new old stock). Since it's a 3600rpm motor, I lose a lot of torque with the VFD, which is also powering my 2hp KMG, and another 2hp Baldor with 9"disc. I'm going to get a 1-1/2 or 2hp, 1800rpm motor for Nathan's disc.

The steel disc does want to spin a bit more after switching off than the aluminum disc did, but it's not an issue AT ALL. I also run the disc pretty slow. I turn the run switch to off, stop the disc on the backside with my hand, flip the fwd/rev switch, and flip the run switch again--- and away I go.


I have used Nathan's disc quite a lot more, and it is quite simply the cat's pajamas. With my carbide file guide, I knocked the guard shoulders in close on the blade with a 50X belt, but then went to the disc with 120X paper. It cut the shoulders in dead nuts flat with a beautiful finish in about a minute. :thumbup: :cool:
 
Nick,

Give us a pic of the shoulder grind off the disc. Are you working a near 90 angle?

I've got one of nathan's discs in the mail and am looking forward to playing with it.

John
 
John, you'll love it my friend! :)

That knife is just about finished, so I can't get a picture of the shoulders... but I'll try to get a shot on the next one. :) The shoulders were fairly sharp, but only about 1/16" wide- so not much of a step down to the tang.

Thanks folks :)
 
You must log in or register to reply here.
Back
Top