New Disc grinder

DukeHarley said:
So after talking with you guys I got to thinking…….if you guys aren’t gettin my point as to what’s wrong then maybe I’m explaining myself wrong and possibly the guy at AMK is confused. I sent him some video and he called me again. We re hashed out what the issue was and he thought I meant concentricity was out but it’s the but perpendicularity of the unit between shaft and face of disc. We got it hashed out and a new disc will be on its way.

I did some more measurements…….shaft is .625 on the money but bore in disc is .628 and I believe either not bored perpendicular or tapers slightly.

Anyway cooler heads prevail and it’s worked out. Some issues with articulation on my part I believe. Sorry guys!
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The I.D. is probably "bell mouthed". Tapered.

I'm trying to think How they did it, and where is there inspection.
I would TELL them to mount it to a shaft, and inspect your new one Before shipping...... Otherwise, they are Just wasting your time.

Good luck, let us know.
 
The Nielsen magnetic disc is within less than .004". When Rod was designing these he was very very adamant that these discs were very precise. I have 3 of these units and they are all made with very high precision. Love the option of having multiple discs with different grit paper with the precision.
Jim
 
Boatbuilder said:
The Nielsen magnetic disc is within less than .004". When Rod was designing these he was very very adamant that these discs were very precise. I have 3 of these units and they are all made with very high precision. Love the option of having multiple discs with different grit paper with the precision.
Jim
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I have Nielson 5 discs and can never go back to having only 1 disc.
 
Boatbuilder said:
The Nielsen magnetic disc is within less than .004". When Rod was designing these he was very very adamant that these discs were very precise. I have 3 of these units and they are all made with very high precision. Love the option of having multiple discs with different grit paper with the precision.
Jim
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I was considering the Neilsen hub/disks. But AMK also sells a Hub with magnets and flat discs. I was quoted $250 for the Hub and 1 flat disc. They don't show the magnetic hub as a separate item on the AMK, but they do show a complete unit with motor and vfd that has the magnetic hub and flat discs, so I reached out to them via email and Allen got back to me with that price.

I'm hoping the OP's issue was a one-off mistake. It seems it would take a pretty sloppy machinist to get that far off.

I ordered an OBM base unit today. I have a Leeson motor and a VFD. All I need is the hub and disks.
 
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fitzo said:
With the Nielsen system, you deal with Nielsen. Nice guy. "Good will" still has value in business.

Disclosure: I own an AMK horizontal grinder.
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Do you find that the plates slip on the hub at all, since there is nothing like a keyway for the plate? I've seen video of the Neilsen Hub/Plate system, and the magnets look pretty strong. But it seems Neilsen could have used the keyway of the arbor, and just made the hole in the plate just like the hub and you could have the arbor with the keyway stick out just a hair so that it would keep the plate from slipping at all. That is how the AMK plate/hub is. You install the hub so that the arbor protrudes with the key just under an 1/8". So that along with the magnets the key is guaranteed security that the plate will not slip. One of the attached pictures is the front side with the plate installed showing the hole on the plate matches the arbor. One issue I might see with the AMK is that the hub area for the arbor is a bit wide, or so it looks. I've got an email into AMK asking how wide it is. Not sure about the hole size on the OBM grinder. One thing about the AMK is that you could use more of the disk surface in the center, being that the disk hole matches the arbor/keyway.
 

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oceanrider said:
Do you find that the plates slip on the hub at all, since there is nothing like a keyway for the plate? I've seen video of the Neilsen Hub/Plate system, and the magnets look pretty strong. But it seems Neilsen could have used the keyway of the arbor, and just made the hole in the plate just like the hub and you could have the arbor with the keyway stick out just a hair so that it would keep the plate from slipping at all. That is how the AMK plate/hub is. You install the hub so that the arbor protrudes with the key just under an 1/8". So that along with the magnets the key is guaranteed security that the plate will not slip. One of the attached pictures is the front side with the plate installed showing the hole on the plate matches the arbor. One issue I might see with the AMK is that the hub area for the arbor is a bit wide, or so it looks. I've got an email into AMK asking how wide it is. Not sure about the hole size on the OBM grinder. One thing about the AMK is that you could use more of the disk surface in the center, being that the disk hole matches the arbor/keyway.
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While that does seem like a decent idea to make the plate more secure, I'll simply say that you have to PRY the Nielsen discs loose. Not easy, barely easy enough. With my arthritic 72 year old hands I have cursed getting the suckers off more than once. I have seen no hint of slippage, but perhaps others with the system can attest to it, also. Strong magnets.

I would suspect the AMK disc is of the same good quality as my horizontal. It has a couple niggles but it has been okay for me. My issues come with the owner's treatment of customers.
 
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That is a solution with no problem to apply it to.

You won't get the disc to slip. As Fitzo pointed out, it takes some doing to remove it. When you put a new disc on it goes, "SNAP" as the magnets pull it down tight on the disc. I always pull my fingers back fast scared I might get my skin pinched.
 
Stacy E. Apelt - Bladesmith said:
That is a solution with no problem to apply it to.

You won't get the disc to slip. As Fitzo pointed out, it takes some doing to remove it. When you put a new disc on it goes, "SNAP" as the magnets pull it down tight on the disc. I always pull my fingers back fast scared I might get my skin pinched.
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Talking to the AMK guy, he seemed to indicate that over time the magnets might weaken, and it would slip, and that his design remedies that. And I do like that his design has more surface area, due to the smaller hole in the plate.

I'm still leaning towards the Neilsen based much on my customer service experience vs the other. I spoke with Rod, he's definitely very customer service oriented and helpful. I asked why his center flange was so much larger than the arbor. He didn't have any good reason other than that is how he first did it and has not changed it LOL

Anyone here have the Neilsen with an Origin Blade Maker (OBM) base? No problem with the work rest with the Neilsen installed?
 
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