Precision Ground Toolroom Stones

[aliva]

Very good video, but in all reality does the average hobby machinist need to get the stones that flat, I think its overkill. yor just removing burs
I recently bought some Japanese water stones for knife sharpening, 200 grit, 4000 grit and 6000 grit. there were around $60:00 each.
I also bought a flattening stone for $50:00 and a cleaning stone for $30:00 does everything I want and does a darn good job sharpening knives.
I also have a sharpening steel, but it's ceramic at 8000 grit

 

[jbolt]

Very good video, but in all reality does the average hobby machinist need to get the stones that flat, I think its overkill. yor just removing burs

I'm not sure how many hobby machinists even think about stoning precision surfaces. From the outset it seems like a bad idea ,and could be if you used "any stone". Once you understand that with the correct stone and technique you won't damage the precision surface. Robin did a good job of explaining that in his video.

There are lots a precision mating surfaces that stack up in our work holding that benefit from good machine practices.

I know I have gotten some sideways looks when I take a stone to the spindle nose and back of a chuck or a tool with a tapered shank. As we move around our not-so-hard big clunky chucks and vises or have a bunch of tools with precision ground shanks floating around together in a drawer they get bumped and nicked and need to tuned up occasionally.

I'd bet money I'm not the only person who has drilled a hole too close to a parallel and turned that nice crisp ground edge into a saw tooth. With a proper stone and technique that can be cleaned up without further damaging the parallel.

 

[Doubleeboy]

Did Robin mention in the video what diamond wheel he used on surface grinder? If he did I missed it.
Thanks!

 

[Bob Korves]

Did Robin mention in the video what diamond wheel he used on surface grinder? If he did I missed it.
Thanks!

7" O.D., 150 grit, 1-1/4" bore, 1/2" wide, 1/8" thick resin bonded media, 100% concentration. I just ordered one of that description from Shars, p/n 505-2233. $81.00 plus freight from Shars, $91.00 and free shipping on eBay. I went with the eBay order, saved about five bucks. I also ordered the stones today, Norton 6 x 2 x 1" combination aluminum oxide, part number 05108568. $15.99 each.

 

[ddickey]

Every mounting hole I see is for 1-1/4". My grinder takes 3/4"

 

[chips&more]

Every mounting hole I see is for 1-1/4". My grinder takes 3/4"

OK, but isn’t it a simple lathe operation to make a bushing reducer. Or, am I missing something? My little Sanford has a 1/2” spindle. All my wheels have 1 1/4” holes. I just made some bushings. And the arbor flange and washer still catch the sides of the wheels. All is good now. Note; make sure you use a paper washer on each side of the wheel when mounting…Dave

 

[Bob Korves]

Every mounting hole I see is for 1-1/4". My grinder takes 3/4"

1-1/4" with a 3" spindle taper per foot is a very common size for surface grinder wheel adapters (hubs). What kind of grinder are you contemplating using? This project requires an accurate grinder and flat and true chuck, a smooth running and tight spindle without runout, and a wheel with near zero runout (well dressed.) Not sure yet, but it might require coolant as well. If you do not have all that, you will not achieve what is needed to make quite flat stones with quite flat abrasive surfaces with a large surface area so they will work correctly. Make sure you understand what Robin is achieving in the video. It is incredibly cool, but not easy to achieve.

 

[woodchucker]

Every mounting hole I see is for 1-1/4". My grinder takes 3/4"

Got a lathe? Make a bushing.

 

[silence dogood]

This may be a silly question. Robin rubs his stones back and forth. Would it not be better to rub them in a figure 8 motion? I was wondering if that would help keep them flat.

 

[Bob Korves]

This may be a silly question. Robin rubs his stones back and forth. Would it not be better to rub them in a figure 8 motion? I was wondering if that would help keep them flat.

Ask Robin the answer to that as a comment to his video. He is so far ahead of me that I would not presume to know the answer. You can bet there is a well considered answer. Robin does not do things "just because." Robin is the most talented machinist I have seen yet, not that I am any kind of an expert. Seriously, ask him, and then report back with what he says...

(I got my two stones yesterday and the diamond wheel for my surface grinder today. Ready to get started...)