A couple of sharpening questions

[Realysm42]

I've been using an edgepro for a few months now and am enjoying the journey - I can get reasonably good results with the Matrix stones. I have a few questions that I've not been able to find information on and would appreciate your input / advice please:

• Three of the five Spyderco knives I've purchased (all brand new and from reputable dealers) have this odd 'dull' spot at the base of the blade (right under the hole). Here are some examples:

The images above are from a Paramilitary 2 and a Para 3. My Para 3 in Maxamet doesn't have this issue so I'm wondering is this normal or am I very unlucky? I love the aesthetics, ergonomics and performance of these knifes, but I've not been massively impressed with the factory edge that came on them, the grind at the tip of the blade has been somewhat uneven on most of them as well.

• I used the 80 grit matrix to remove the dull spot on the Para 3 S110v; as I did this, I noticed the 80 grit matrix stone shed a lot of material, which I found alarming (none of the other matrix stones behave like this, even upon first use). Yes, I did give them a light dressing prior to first use. D Diemaker it'd be great if you can let me know what you think please? Here is a picture:
  

All the loose material on the knife came from the stone - after a bit of use it seems to have calmed down though.

• Finally, I got some water on my Maxamet blade and it's left these spots on both sides of the blade:
  

I know it's not a stainless steel, so reacting to water is to be expected, I gave it a quick rub down with 1200 grit sandpaper, so they're very subtle now - if you were me, would you be concerned about these marks or are they safe to leave?

Any of your advice is greatly appreciated by me - thanks!

 

[Glock Guy]

The dead spot in front of the plunge grind is a typical Spyderco thing, and I've only NOT seen it with my new Sage I in Maxamet. Spyderco sharpens their blades on a belt system (and quickly), so they don't go all the way to the plunge grind. It will go away with some sharpening's, but typically I try and take care of this with the first sharpening using some stones with a nice, sharp edge, as it is ugly.

Maxamet will patina very quickly, so if you don't want any other color added to the blade I would suggest using something to protect it. I've used EDCi from Aegis solutions on my non-stainless blades and it works great. Of course I live in ND where humidity is not an issue, but if you live in the south your results may be different. I always clean my blades with denatured alcohol after sharpening to make sure I get all the water off them, then I reapply the EDCi.

The spots look like faint patina so you could probably even take them out by rubbing it with something like Flitz, or some other metal polish. Some people like the patina look, others don't. If you don't, you'll need to apply something to the blade to keep it from happening, and be sure to clean the blade really good after you sharpen it with water.

 

[Diemaker]

Yikes, that 3rd photo shows a lot of diamond on your knife! That isn't normal and it is from how you are using it. Without knowing exactly how you used the stone and what the bevel looked like to begin with my advice is only general. I would say use lighter pressure until the stone stops shedding grit and focus on edge trailing strokes, especially once you reach the apex. Having the diamonds come into contact with your blade where the bevel and blade body meet is smoother than pushing them into the sharp apex. It really shouldn't be shedding any grit after the first knife after a fresh dressing. Looking at how much diamond is on the bevel you might need to dress it again if it doesn't cut as it should. With that much grit lost you might need to flatten it anyway. The only time this happened to me was when I reprofiled some scissors to better cut hair with a .04"-.06" bevel when I was done. It was taking too long so I used a little too much pressure for the small bevel, .01" ish to begin with. While the stone did shed too much grit, and lost about .004" of thickness, the grit did dress the stone well and it kept cutting. The only harm was the .004" dish I ended up with.

Were you reprofiling when you lost all that grit? Was the stone brand new?

Based on the one new Spyderco I have purchased, a Native 5 Maxamet, the factory edge sucked. The grind was off about 2 degrees from one side to the other, no big deal, not perfectly even, and the edge was soft. The first job I used it on was cutting up some carpet and the edge rolled, not what I was expecting. After several sharpenings it is now what I expected, and love about it. Don't worry about the uneven grind. You can fix it in the first sharpening or take your time as you use the knife. I personally don't want to pay Spyderco to do a great sharpening job, and then have the distributors and retailers mark it up, so I don't see this as a problem.

I like a choil to end the bevel at the plunge line so I don't wear the corners of my stones trying to get to the end of the bevel. Just a little one big enough to clear the bevel.

Here is a video I did sharpening my Maxamet knife with Matrix stones that you may find interesting. I start sharpening the knife about 5:30 into it.