Need advice for maintaining BM940

[aggiegrads]

I just purchased a Benchmade 940. I also have a Spyderco Sharpmaker on the way. My question relates to the factory angle on the 940.

My goal is to not let the edge get so dull that it needs re-profiling. What is the best way to maintain the edge with my new Sharpmaker? Which stones, and what angle?

 

[yoda4561]

First reprofile the edge to match the sharpmakers finest angle, I think those are the 15/30 slots. Then for touchups just give it a pass or 2 at the 20/40 degree with medium or fines stones (depending on if you prefer a finely polished or slightly toothy edge).

 

[aggiegrads]

First reprofile the edge to match the sharpmakers finest angle, I think those are the 15/30 slots. Then for touchups just give it a pass or 2 at the 20/40 degree with medium or fines stones (depending on if you prefer a finely polished or slightly toothy edge).

Thanks. How many passes per side can I reasonably expect to re-profile? 100? 1000? 10,000?

 

[yablanowitz]

That depends on the stock edge bevel from Benchmade. Unless they have improved in the couple of years since I bought one, that could be anywhere from thirty degrees included (a perfect match for the narrow angle) to over forty degrees (lots of strokes depending on blade steel and how much of the edge is that thick). I always rebevelled mine on diamond hones, so I have no idea how long it would take on a SharpMaker. I will say the SM is not the ideal tool for hogging off a lot of steel.

To check the stock angle, blacken the edge bevel with a magic marker and take a couple of passes on each side with the SM rods in the 15/30 holes (15 degree per side/30 degrees included). If the marker is removed at the edge, the bevel is less than 30 and you are good to go maintaining your edge on the 20/40 setting. If the marker is all removed, you have a match at 30 and you are good to go. If the marker is removed at the shoulder where the edge bevel meets the main grind, it is over thirty. Try the same thing with the rods in the 20/40 holes. The bevel may be over thirty but under forty, so maintaining on the 20/40 setting may still be possible. If it removes the marker at the shoulder on the 20/40 setting, you have a lot of work to do. You may want to check a few of these threads for faster ways to rebevel.