Using the Stone grader

[bnlsrv]

I was just wondering about a few things in regards to using the stone grader. Should I be concerned about how the stone will wear out- should I put pressure in the middle, front or rear part of the stone as it contacts the supergrind wheel?

How much if any does the stone grader wear out the wheel?

Finally, if you have to do a number of chisels, do you do all of them at 220, and then do all of them at the finer grade, or do you do them one at a time regrading the stone after each chisel?

[Ed]

If you watch Jeff's videos or dvd you will  see he really leans on the grader.  There is a whole lot of stone there, so when the stone gets to where you want it to be STOP.

I personally would do all the rough cutting at once and then reface the stone and then do the final cutting.  I think this way you will save alot of wear on the stone and you will get more uniform cuts

[Jeff Farris]

Once a chisel is mounted in the SVH-60 Straight Edge Jig, you want to go through the entire grinding process without removing the tool from the jig.  Frequent grading of the stone has a minimal effect on the grindstone diameter and keeps the stone clean and free-cutting.  Trying to do multiple tools with the 220 surface, then grading will lead to more work, more time spent aligning the chisel to the grindstone, and a bit of frustration from not getting the alignment perfect.  

20 to 30 seconds with firm pressure should be sufficient to change the stone in either direction.  When grading the stone to the 1000 grit finish, the grader will wear.  Once a curve is cut into the grader, it will polish the grindstone more efficiently.  I use the grader at the extreme ends, rather than in the middle.  This gives me twice the life from the grader.  I also use a very slight side-to-side motion to minimize crowning the grindstone.  When returning the stone to 220, don't be afraid to start by using the corner of the grader, which will scarify the grindstone surface more quickly than the flat surface.

[FarrellPiano]

I find that I need to true the grindstone with the ADV-50D Diamond Truing Tool after sharpening just two blades or so. My SP-650 Stone Grader technique seems to be crowning the grindstone. Could you please expand on your "very slight side-to-side motion" technique for grindstone grading? Do you shoot to develope any particular profile on the stone grader?

[Tim N]

I found the same thing. I had to true the stone only after a few tools. This was very concerning to me as well.

[Jeff Farris]

Farrelpiano and Tim N:

Give me a couple days to bring together a thorough answer to this.  I want to shoot some photos of a grader that I have used extensively, to show you what I mean.  In the meantime, I end up with two curved profiles in the smooth side of my stone grader, one on each end.  That way, I get twice the life from a stone grader, and in my opinion, it is easier to keep the stone flat, rather than working in the center of the grader.  Scrubbing side to side will inevitably create a crown in your stone.  Put the section of your palm that is at the base of your thumb on the back of the stone grader with it directly over the center of the grindstone.  Press firmly, holding the opposite end of the grader with your other hand, maintaining it horizontal.  Move side-to-side no more than 1/4 inch back and forth.

[FarrellPiano]

Your couple days are up Jeff! It's been almost a month!  

Seriously though, have you had a chance to put anything together to clarify all this? Photos would be great. I really don't have a clear picture of exactly what you are describing in your process. Thanks.

Terry Farrell

[Tim N]

Jeff, where are you???

[Jeff Farris]

I'm here, just really busy.  We're moving our offices to Springfield, MO from Grain Valley (Kansas City area).  The building is my first priority, and then we have to move everything....this is all while maintaining a schedule of weekly demonstrations.  Sorry guys, but shooting pictures of my hands on a stone grader will have to wait until I get moved and my photo gear out of the box it has been hidden in for a couple months.  

Take a closer look at the second video in the chisel demonstration...I think it is pretty well shown there.