Grind progression...sort of

[Blackdirt cowboy]

How do y’all know when to go to the next higher grit when grinding the bevels? Obviously, it’s when you remove all the scratches from the previous belt, but how do you know definitively when that is accomplished?

Tonight, I put dychem on the bevels after grinding, but after three passes at the next higher grit, it was gone. It’s hard for me to believe that three passes removed all the scratches, so I kept grinding until it looked good to the naked eye, then progressed up the grits.

Finally, I made it to a 9 micron grit belt. Not because I want to put a mirror finish on my knives, I don’t, because they are working knives. But I did it because I knew any scratches I didn’t remove would show up. Here is what it accomplished.

This pic looks pretty good, except for the two vertical scratches toward the front of the blade.

This pic, with the blade held at an angle to the light, shows the scratch pattern better. It’s obvious I didn’t remove one long scratch up towards the front. For the most part, it is a mirror finish, but there are still imperfections. So, how can I know that I’ve removed all the scratches of the previous grit before moving on?

I will ultimately take this knife back down to 600 grit and it will be ok. I’m just trying to perfect my craft and would appreciate any tips y’all can give me.

 

[A.McPherson]

Grind at different angles for each grit. That'll give contrast between one grit and the next.
Same thing with hand sanding.

 

[Blackdirt cowboy]

That’s a great idea for a flat grind. I’m not sure I could do it on these hollow ground knives and still keep my rind lines straight.

 

[Jesse Latham]

Looks like a 2" belt bump to me. It's caused by hitting the plunge line with the edge of the belt. That makes the other edge of the belt dig in and leaves a mark(divot).

 

[weo]

but how do you know definitively when that is accomplished?

When you can't see them anymore. But as mentioned above, you need to change directions a little each time you move to a higher grit so that your scratches are crossing each other.

Take the time to look at the blade at different angles, moving the blade around so you are flashing the light glare all around the blade (here's where having a bright spot light helps, exactly like what you don't want when taking pictures of your knives). Sometimes I'll spend 2-3 minutes looking at a spot at different angles, while moving the blade around to make sure there aren't any scratches going the wrong way.

 

[TheEdge01]

You can get a relatively smooth grind on a course belt by controlling the amount of pressure you are applying. Also, control the speed of your passes while grinding. This will allow your grinds to be nice and even. Make sure your knife is flat against the belt and keep a steady speed until you make a full pass.

 

[AVigil]

You have a 2" mark.

That is from keeping the blade flat up against the platen or wheel, while working the plunge.