Fred:
I’ve probably done more than anybody else in evaluating the effects of “slop” in the stones. I installed bronze bushings in my stones – and reduced the error to almost zero. For the last month or two, I’ve been running a new pair of unmodified 800/1000’s and I really can’t see much difference in the bevel angles.
The effects of the looseness in the bores sliding along the rods can be minimized by keeping your grip point below the edge as much as possible. The really noticeable errors show up where you apply pressure above the edge, causing the stone to tip (rock) over. See the photos in my post on page three of “My First week with the WEPS” https://knife.wickededgeusa.com/forum/6-techniques-and-sharpening-strategies/13009-my-first-week-with-the-weps?start=20#17882
I’ve found that there can be some variability in the “stone thickness” from the factory. I use the VSTAs (SWAT) with every grit change and have seen that I have to make a small microadjustment on a couple of unmodified stones when I am just turning the stone from one grit to the next. The difference is about 1/4 turn of the screw, which amounts to about 0.1 degrees. I can see the effects of 0.1 degree, but only at the higher grits; 800 and above.
If you see really big differences in your bevel angles, I’d first look at how securely the blade is clamped in the vise. Many of us have learned the hard way that an improperly clamped blade can move from side to side. Until you recognize it, it’ll drive you nuts.
My advice? 1. Learn to use the SWAT and make it a routine part of your process. 2. Always check for a secure mount by twisting back and forth on the handle to see if it will move. 3. Keep your grip low on the stones and avoid going high enough to roll the stones over the edge.
Good luck.
.
