grinder wheel replacement

[Roger Chandler]

My 8 inch slow speed grinder came with a 60 grit gray wheel and a 120 grit white aluminum oxide wheel. It has worked pretty well for the last year, but as of late I am noticing that the wheel loads up with metal a lot faster than it used to, and I seem to be having to use the diamond wheel dresser a good bit more often. Is this due to some change in the consistency of the wheel?

Also, if I purchase a new wheel, I want to get one that will give a good grind with as minimal tool wear as possible. Some turners use the pink wheels, and some blue wheels. Which is best and why? I have both high speed steel, and cryogenic steel gouges, and want a stone that is true running. Is there a better quality wheel from Norton for example, or from some other source?

Your help would be much appreciated!

 

[Sean Troy]

Norton K wheels are hard and less friable(sp?) cost more but a lot of turners swear by them.

 

[Steve Worcester]

If there is a Woodcraft in your area, the (Camel) pink wheels work well and are reasonably priced. I like the One-way wheels also.
As far as balanced, some of that is the wheel, but the grinder also makes a huge difference. On a cheap grinder, you would need to use a wheel balancing system, like One-Ways, or try unscrewing and moving, re-tightening the wheels to find a spot that works better than the other. Maybe more tedious that it is worth.

 

[Roger Chandler]

Never thought of repositioning

If there is a Woodcraft in your area, the (Camel) pink wheels work well and are reasonably priced. I like the One-way wheels also.
As far as balanced, some of that is the wheel, but the grinder also makes a huge difference. On a cheap grinder, you would need to use a wheel balancing system, like One-Ways, or try unscrewing and moving, re-tightening the wheels to find a spot that works better than the other. Maybe more tedious that it is worth.

Steve,

Thanks for the suggestion about repositioning the wheel to see if it will run truer. I don't think it is a waste of time, but it might help. My grinder is a Steel City, VS and is a clone of the Delta VS model. Same grinder, just a different label I guess.

I did order a couple new wheels from Hartville Tool today. One is a 100 grit Norton SG, ["K" hardness,and the other is a Norton 3x in 120 grit["I" hardness] and I think I will like them, and get a cooler grind as well as a friable surface, especially for touch-up grinding and avoid bluing the tools from heat.

Thanks for your input, I appreciate your time and help.

 

[Wayne Spence]

Grinding wheels

Lyle Jamieson has a section in his video about correcting any wobble from side to side. That is- the wheel does not stay in the same plane perpendicular to axis of the shaft when rotating. What an imperfect world with so many perfect techniques.

 

[Bill Boehme]

Roger,

The aluminum oxide wheels, whether white, pink, blue, aqua, fuchsia, or chartreuse are better for your turning tools than the gray silicon carbide wheels because the steel will not get as hot. Despite statements about HSS keeping its temper when heated, that is partially true, but some folks take it too literally. If heated too much, a keen edge can become somewhat brittle and thus become dull quicker than an edge that is kept cool when sharpening. The cheaper white wheels will either wear out fast or hardly at all depending on their rating, so a rating of J or K is probably about the best choice for turning tools. When truing up a wheel with a diamond dresser, use an extremely light touch so that you are just hitting the high spots -- otherwise, it is easy to exacerbate an out of round condition by "riding" the surface of the wheels. Since your hand behaves like a weighted spring when trying to maintain a certain pressure when holding the dressing tool, a harmonic condition can be created that causes accentuated humps and valleys.

I would say that essentially all of the vibration is due to the grinding wheels. To check this out, remove both wheels and run the grinder. I bet that it will run very smoothly when running without the wheels. Something else that I do not believe has been mentioned anywhere is the difference in smoothness of a four pole motor (1750 RPM) vs. a two pole motor (3550 RPM). The four pole motor will run smoother than a two pole motor (i.e., the torque ripple will be much less). A four pole grinder motor has at least a couple benefits that I have not seen mentioned previously:

1. Due to the lower angular momentum, the same out-of-round wheel will vibrate less on a four pole motor.
2. The torque ripple kick from a two pole motor will "excite" an out-of-round wheels much more than the low ripple from a four pole motor.

I am a fan of truing up a wheel as opposed to using a balancing kit, but the balancing kits work quite well. Unless, the grinder is solidly mounted, truing would be difficult to do.

 

[Roger Chandler]

Thank You BILL

Roger,

The aluminum oxide wheels, whether white, pink, blue, aqua, fuchsia, or chartreuse are better for your turning tools than the gray silicon carbide wheels because the steel will not get as hot. Despite statements about HSS keeping its temper when heated, that is partially true, but some folks take it too literally. If heated too much, a keen edge can become somewhat brittle and thus become dull quicker than an edge that is kept cool when sharpening. The cheaper white wheels will either wear out fast or hardly at all depending on their rating, so a rating of J or K is probably about the best choice for turning tools. When truing up a wheel with a diamond dresser, use an extremely light touch so that you are just hitting the high spots -- otherwise, it is easy to exacerbate an out of round condition by "riding" the surface of the wheels. Since your hand behaves like a weighted spring when trying to maintain a certain pressure when holding the dressing tool, a harmonic condition can be created that causes accentuated humps and valleys.

I would say that essentially all of the vibration is due to the grinding wheels. To check this out, remove both wheels and run the grinder. I bet that it will run very smoothly when running without the wheels. Something else that I do not believe has been mentioned anywhere is the difference in smoothness of a four pole motor (1750 RPM) vs. a two pole motor (3550 RPM). The four pole motor will run smoother than a two pole motor (i.e., the torque ripple will be much less). A four pole grinder motor has at least a couple benefits that I have not seen mentioned previously:

1. Due to the lower angular momentum, the same out-of-round wheel will vibrate less on a four pole motor.
2. The torque ripple kick from a two pole motor will "excite" an out-of-round wheels much more than the low ripple from a four pole motor.

I am a fan of truing up a wheel as opposed to using a balancing kit, but the balancing kits work quite well. Unless, the grinder is solidly mounted, truing would be difficult to do.

Hello Again Bill,

I love it when guys who know a lot more than me can give me info that helps me avoid the "buy it before you try it" syndrome, because it saves me $$$$ in the long run, not to mention all the frustration that goes along with having to do it over and over again....😀

Thanks for taking the time... I am grateful!

 

[Roger Chandler]

warped wheel

Lyle Jamieson has a section in his video about correcting any wobble from side to side. That is- the wheel does not stay in the same plane perpendicular to axis of the shaft when rotating. What an imperfect world with so many perfect techniques.

Hi Wayne,

I think the problem with the wheel on my grinder [white one] is not that it is not truly perpendicular to the arbor on that axis, I think the upper 1/3 of the wheel is just plain warped. It is almost like when it dried from manufacturing that it warped, and instead of putting a true one on it, the China Manufacturers once again just sent something to America that should have been eliminated by the Quality Control inspectors......

But Alas, I guess I am just dreaming again.......because getting it right the first time doesn't seem to be in the vocabulary of some vendors..... but I digress.....🙁

 

[Roger Chandler]

Norton 3x wheels

I ordered and received the Norton 3x wheels,but the plastic bushings that came with them cause a lot of vibration. I ordered 2 drill bushings from McMaster-Carr, and received them the very next day.

They really do help the wheels to run true, and minimal dressing was needed to smooth everything out.

McMaster Carr has really impressed me with their customer service. The were exceptional to say the least, and the drill bushings fit the wheels like they were machined especially for the norton wheels.

 

[Bill Boehme]

I ordered and received the Norton 3x wheels,but the plastic bushings that came with them cause a lot of vibration. I ordered 2 drill bushings from McMaster-Carr, and received them the very next day.

They really do help the wheels to run true, and minimal dressing was needed to smooth everything out.

McMaster Carr has really impressed me with their customer service. The were exceptional to say the least, and the drill bushings fit the wheels like they were machined especially for the norton wheels.

I agree with what you have experienced. I have never been impressed by the slightly loose fitting soft plastic bushings that come with grinding wheels because they have too much free play and also have the potential for allowing the wheels to shift slightly over time. The only nice thing that I can say about the plastic bushings is that they come in "pretty" colors.