WIP Steel grinder disk machining

1/2 mile from Earnhardt's shop huh? That means I live either 4.5 or 5.5 miles from you. Nice job on the disks and that weld looks amazing! Wish I needed another disk...wait I might need one after all.
 
Seems like 7/8" shafts are pretty common on 1+ hp motors. 5/8" seems standard on 56c motors. I haven't seem any 3/4" diameters. Maybe the 3/4" is meant to be mounted to the drive wheel shaft?
 
Tin.Man said:
Nate- Your tig welding is the nicest I have ever seen and I grew up with a family of welders. Jesus man, beautiful job!
Click to expand...

It's funny, whenever I do a WIP thread I'm always surprised by some small thing that people pick up on that I didn't anticipate, in this case the weld. I don't think my welding is anything special, so your accolades were unexpected and made me feel real good. :o

Thanks.

I think this group here in particular is somewhat unique because you all recognize and appreciate skilled work more than most people today. A lot of folks might look at that and say "ew, it's discolored and the weld is bumpy like a stack of dimes, you need to grind that smooth and paint it." It's a knowledgeable person who can find a weld beautiful. :thumbup:
 
Barry Clodfelter said:
1/2 mile from Earnhardt's shop huh? That means I live either 4.5 or 5.5 miles from you. Nice job on the disks and that weld looks amazing! Wish I needed another disk...wait I might need one after all.
Click to expand...

5.5 miles. I used to live in Corn-hole-e-ious, we were about neighbors.

Come on by some time. (Don't tell anybody, but the dogs don't really bite.)
 
PT Doc said:
Seems like 7/8" shafts are pretty common on 1+ hp motors. 5/8" seems standard on 56c motors. I haven't seem any 3/4" diameters. Maybe the 3/4" is meant to be mounted to the drive wheel shaft?
Click to expand...

It makes sense to me to mount a disk to a spindle of some sort. An electric motor isn't built properly for the application, though it must work well enough because everybody does it.

A real spindle will generally have two matched radial ball bearings mounted against each other with some amount of preload at the working end of the bearing and a third bearing on the other end of the shaft that free floats to accommodate thermal growth of the spindle. Electric motors incorporate none of these attributes and instead deal with the rather significant thermal issues in an electric motor by allowing the spindle (and I'm using the term spindle pretty loosely here) to have end play.

...anyway, I'm rambling...

I think most folks use a 56C for this. They can be had in higher HP, but I don't think you need as much HP as you would grinding against a platen on a belt grinder. What are your thoughts on this?
 
Typically, the "commercial" models of these knifemaker 9 inch disc grinders have 1/2 to 1 hp motors.
Nathan the Machinist said:
It makes sense to me to mount a disk to a spindle of some sort. An electric motor isn't built properly for the application, though it must work well enough because everybody does it.

A real spindle will generally have two matched radial ball bearings mounted against each other with some amount of preload at the working end of the bearing and a third bearing on the other end of the shaft that free floats to accommodate thermal growth of the spindle. Electric motors incorporate none of these attributes and instead deal with the rather significant thermal issues in an electric motor by allowing the spindle (and I'm using the term spindle pretty loosely here) to have end play.

...anyway, I'm rambling...

I think most folks use a 56C for this. They can be had in higher HP, but I don't think you need as much HP as you would grinding against a platen on a belt grinder. What are your thoughts on this?
Click to expand...
 
Nathan,

I always like your WIP's; so much valuable information. It must be fun making a living as a "Dastardly Machinist".

I was interested when you first floated this idea out there a couple of months ago, and now I just have to have one of the 1 degree discs. Are you going to post the price in the "for sale thread" when they are ready, or via PM/email?

Thanks for the time you spend educating the masses.

Jeff
 
If the disk goes right on the motor/no you really dont need much HP.
It is direct drive.
Eddie
 
Iwannashoot said:
Nathan,

I always like your WIP's; so much valuable information. It must be fun making a living as a "Dastardly Machinist".

I was interested when you first floated this idea out there a couple of months ago, and now I just have to have one of the 1 degree discs. Are you going to post the price in the "for sale thread" when they are ready, or via PM/email?

Thanks for the time you spend educating the masses.

Jeff
Click to expand...

:thumbup:

email sent
 
Very interested in one as well. I was just telling my wife earlier that I need to make my VFD portable to run a disc and my Bader. Will be looking forward to a tapered one.
 
I know this has been said a lot already but, that really is some fine welding you did there. I weld for a living, among other things, and I don't think I've ever had a weld turn out that beautiful. Really, very nice.
 
Nathan the Machinist said:
It makes sense to me to mount a disk to a spindle of some sort. An electric motor isn't built properly for the application, though it must work well enough because everybody does it.

A real spindle will generally have two matched radial ball bearings mounted against each other with some amount of preload at the working end of the bearing and a third bearing on the other end of the shaft that free floats to accommodate thermal growth of the spindle. Electric motors incorporate none of these attributes and instead deal with the rather significant thermal issues in an electric motor by allowing the spindle (and I'm using the term spindle pretty loosely here) to have end play.

...anyway, I'm rambling...

I think most folks use a 56C for this. They can be had in higher HP, but I don't think you need as much HP as you would grinding against a platen on a belt grinder. What are your thoughts on this?
Click to expand...

Mounting on a spindle makes since I already have a motor for the grinder. Could be easily setup on the end of the drive spindle or somehow powered of the drive shaft with another pulley and a modular table.

When you are talking about bearing are these in the form of pillow blocks or flange bearings? From your description I don't think so but I'd like to get a better idea.

Please put me down for a one degree 3/4 bore. Please PM one email me further details, pricing. Thanks
 
Since we seem to be discussing motors and discs:

It is EXTREMELY advantageous to have the motor reversible, and also a great boon if it is VS. If I had a choice of a 1HP single speed, uni-directional setup, or a 1/2HP reversible/VS.....I'd take the smaller motor.

This is one of those places where the cheap VS drives that only do up to 3/4HP and the cheap 1/2 to 3/4HP three phase motors have a real use. You can often get the pair for less than $100.
 
i4Marc said:
Nathan,

Any plans on making a run of larger discs, maybe 15"?
Click to expand...


I'm not setup very well to turn disks that size efficiently. At least not in steel. My turning center will swing it, but I don't think it has enough grunt to cut it. The larger the diameter the higher the torque required to make the cut. I think 9" is about the limit for me. Sorry.
 
Nathan the Machinist said:
It makes sense to me to mount a disk to a spindle of some sort. An electric motor isn't built properly for the application, though it must work well enough because everybody does it.

A real spindle will generally have two matched radial ball bearings mounted against each other with some amount of preload at the working end of the bearing and a third bearing on the other end of the shaft that free floats to accommodate thermal growth of the spindle. Electric motors incorporate none of these attributes and instead deal with the rather significant thermal issues in an electric motor by allowing the spindle (and I'm using the term spindle pretty loosely here) to have end play.

...anyway, I'm rambling...

I think most folks use a 56C for this. They can be had in higher HP, but I don't think you need as much HP as you would grinding against a platen on a belt grinder. What are your thoughts on this?
Click to expand...

Is this similar to what you are describing?

http://www.zorotools.com/g/Mandrel/00024515/

Thanks
 
I am running a 1.5 HP Leeson 56c style where I am using the two and one socket approach to share my VFD with the KMG. I think it gives extra torque at low speeds and it was only about $40 on "that auction site" a few years ago. It works great, especially at very low speeds for sharpening. Looking forward to Nathan finishing them up so we can put them to work. -Doug
 
You must log in or register to reply here.
Back
Top