CBN wheels

Re: CBN wheels

mark paulley

Skip,

what is the horse power on each unit?

Re: CBN wheels

JohnV

I have an 8" grinder 1750 RPM. I have a CBN wheel on one side and a 120 grit stone wheel on the other. 99% of my sharpening is on the CBN. I only use the stone wheel for heavier metal removal.

Re: CBN wheels

John lucas

I do the same as John. I ha e a 350 CBN on one side of my 8" slow speed grinder and a 120 grit aluminum oxide on the other. I do that because I have a lot of home made tools that aren't HSS so I grind those on the AO wheel And will regrind some HSS tools on it. 90 percent of everything g else is done on the CBN.

Re: CBN wheels

John K Jordan

As Skip asked, what is the HP of the grinders. 1/2 hp grinders can be a little too wimpy for two steel CBN wheels but should handle aluminum wheels OK. I bought all mine from Ken Rizza at Woodturner's Wonders.

CBN should work OK with the faster grinder but most people like them on slower grinders, may give a bit more control when sharpening.

The grits to get might depend on what you want to sharpen. People who turn big green wood bowls seem to be happy with 180 grit. I prefer turning small detailed spindles and things, sometimes from very hard wood and I want a better edge on some tools so I use a 600 grit wheel for my skews and scrapers, and a 1200 grit wheel on a Tormek for my spindle gouges. But when I want to shape tools like negative rake scrapers, I want a much coarser wheel. I use an 80 grit CBN wheel for shaping but a standard AlOx wheel should be fine. There is no problem with overheating HSS tools as there is with carbon steel so the higher speed grinder would also work for a coarser wheel.

JKJ

Re: CBN wheels

jorge

Skipp,

I got mine from Cindy Drozda, an 80 and a 180 this used the most. 1 1/2" square wheels.

Yu will be glad you got them!

Re: CBN wheels

George Balock

Skipp,

I got my CBN wheels from Ken Rizza at Woodturning Wonders. He has great customer service. I would put the wheels on the 8” grinder, especially if it has the beefier motor.

The difference in rotational speed between the two grinders is dramatically different. The actual speed that the tool sees is about 7200 LFPM for the 8” grinder and about 1800 LFPM for the 6” grinder. I’m not sure if this would enter into your decision making, but you would have a lot more control and cooler tools with the 6” grinder.

Re: CBN wheels

Reed Gray

If you are getting one CBN wheel, get a 180. That will do for about 90% of the sharpening you will need. If you are getting 2, then add a 600 grit wheel. This one makes a difference on fine finish cuts where the 180 edge just doesn't quite do good enough. The 80 grit wheel is okay for some minor profile changes, but kind of slow. If I want to get serious about it, then I use a 36 grit on the big belt sander. 36 grit wheel on a standard grinder works too.

As for grinders, I prefer over built rather than under built. I do prefer the slow speed grinders. The 1/2 hp Rikon is very popular right now, but is way underpowered for my taste. I have the 1 hp Rikon, and it isn't as quiet or smooth as the Baldor grinders, it is a good grinder with lots of power for the price. You may have to tinker with it to get the wheels on and running well. Ken Rizza does sell sets of washers, one concave and the other convex. The reason for them is that the nuts that hold the wheels on are not machined dead flat and this washer system will take care of that. Not an issue with the Baldor grinders, but an issue with the Rikon and other 'cheaper' grinders.

As for which CBN wheels, I have mostly D Way, who was pretty much responsible for making them available to turners in the electroplated versions. They are on steel hubs and fairly heavy. I would think they would be a constant strain on the weaker grinders. There are a lot of them out there, and some suggest at least giving them a hand spin to get them started. The Wheels from Ken are on aluminum and plastic hubs, and are considerably lighter, Still a bit of a strain for the 1/2 hp grinders. Cindy sells the Optigrind wheels. As far as price, the wheels from Ken are the least expensive. The D Way are more. I don't really know if there are huge differences in quality. Probably the highest quality ones might go to Cuttermaster up in Canada. The actual quality differences seem to be minimal. All are spin and bubble balanced, so if they are not running true, the nut is the first thing to check. The arbor shaft on the grinder is the second.

robo hippy

Re: CBN wheels

Bill Blasic

One of the grinders I have is the Rikon 1/2 HP with two CBN wheels on it. It takes 9 seconds to turn up to full speed and takes almost 12 minutes to stop after turning it off. These are 1" wheels both 180 with one straight across and one with rounded corners.

aluminum or steel?

John K Jordan

>>>One of the grinders I have is the Rikon 1/2 HP with two CBN wheels on it. [It takes 9 seconds to turn up to full speed and takes almost 12 minutes to stop after turning it off. /green]

Are those wheels steel or the lighter weight aluminum? I had two aluminum wheels on a 1/2 hp Rikon and I don't remember it taking that long to spin up or stop. I how have one CBN and one polishing wheel on that grinder and it spins up quick enough.

Two aluminum wheels on a 1 hp grinder spin up nicely. All of the grinders I use that don't have braking take a long time to stop. I've never though to time the stops but when if one is still spinning when I want to use it I slow it down with a wooden stick applied to the side of the wheel, just below the wide area with the side grit.

JKJ

Re: CBN wheels

Reed Gray

The Baldor and Rikon 1 hp come up to speed in about 3 seconds max. Never timed the run down time, but the Baldor stops much quicker than the Rikon.

robo hippy

Re: aluminum or steel?

Bill Blasic

Both are steel and weigh as much as a stone wheel. I'm going to take off the rounded CBN and put on one of the original stone wheels back on it. This grinder is going to my daughters place in NC in July as I'm setting her up with complete turning, burning and airbrushing systems. Hopefully a new turner will emerge .