Truing/Balancing Paper Wheels

[Sam Sloane]

Morning All,

I have a brand new Paper Wheel set up now, but having never seen one LIVE, I am thinking there must be tricks to getting them running true, better than what I have. If videos would be helpful, I could post them, to see what I have....

I have a 3/4 Hp dual ended Buffer variable speed.
Main Shaft is 20mm, with 5/8" dia for mounting 10" wheels.
I have flattened the wheels as best I can by clamping for a few days
I replaced the cheap pressed washers with 0.375" thk steel washers, lazer cut.
I block sanded the out diameter of the paper wheels to try to true the ODs

The result works, but I did expect better results....the knife blades still "bump" along while honing.....I wasn't expecting a super balanced result, but I did think it would be better!

Any suggestions?

Sam

   

[EOU]

Here's what we would start with Sam; set something on the work table or attached to the grinder body as a fixed point that is an 1/8th" or closer to the wheel surface and spin the wheel. You get the picture already. Watch the gap between fixed point and wheel surface narrow/widen so that at least you can tell how great the error in concentricity  (our spell checker doesn't like this word) is. At least then you'll know what you're dealing with.

[Mark Reich]

Sorry I didn't finish my reply to you yesterday, Sam. EOU is on the right track.

You have an amazing setup! Certainly one of the best I've seen. You've done everything right, but I'm not surprised to hear the paper wheels aren't running true. I kinda doubt you will be able to clamp the warp out of them, but warp probably doesn't matter as much as concentricity. (yes, spell check constantly needs words added, EOU)

The problem is most likely two fold. The hole in the wheel needs to be a very good fit to the shaft. Sounds like the shaft is metric and the hole is SAE. The two are often close but not close enough for this application. Is there any play between the hole and the shaft, or is it a nice, tight fit?

If the hole isn't part of the problem, or if you have the wheels mounted very solidly and won't need to remove them for any reason, you can fix the concentricity yourself. If you remove the wheels you'll need to true the face again, but it's not a huge ordeal.

Otherwise, you can make or buy MDF wheels to fit your shaft. MDF is stronger, flatter and more stable than paper wheels. James Hammons of Ace Sharpening has specialized experience, and I believe he charges $35/wheel. Pretty sure Mr. Don Bailey uses MDF wheels from Ace Sharpening as well.

[Kwakster]

I have coated the inside of the holes in my Paper Wheels with a few layers of the same woodglue i use for regritting.
Just put on a layer, spread it evenly with a matchstick or nail and let it dry overnight, repeat if necessary.
Not only does it remove any slop there might be, it also holds the round shape better than just the cardboard, which is especially useful for me since i change Wheels often.

At this point in time i have no hands-on experience with MDF for this particular method of motorized sharpening (only for hand strops), but a member of British Blades passed on a warning to me that he received from an English company specializing in polishing equipment, that in the professional world home-made MDF Wheels are considered too dangerous to use.
It seems that they can come apart suddenly due to the centrifugal forces most benchgrinders can create.

[EOU]

Thanks for that bit of information Kwakster. We doubt that MDF users will toss their wheels but it might cause them to put on their safety glasses.

[Sam Sloane]

I came up with a simple way to "grade" the OD.

I took my self designed knife support mounted on the Tormek USB, turned it over, wrapped 60 grit paper to it, so the flat side was just off the wheel. I then turned on the machine, and slowly lowered the device to the wheel, using the adjustment screw on the USB...... sanding out the high spots!

I wont know till tomorrow how much it improved things....as I had to re-treat the wheels with diamond paste...but we will see....

Thank all for the help.....

Sam