Edge Pro Apex question

Komitadjie said:
Don't worry too much about the looks, when you lap your stones to keep them flat (every knife or so, the coarse grits dish more than the fine ones) it will take it right off.
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Okay. What's involved in lapping stones?
 
Well, a waterstone works by letting the grit slowly break out of the binding agent to keep the surface sharp and cutting cleanly. This eventially results in the stone "dishing" or becoming convex in shape. Lapping is how you keep them flat, so that you can take advantage of the precision your EP offers. Lapping is accomplished by just abrading away the stone against a reference surface. There are lots of things you can use to do that. I personally use a DMT diamond plate, mounted on an EdgePro blank. I also use it in place of the 120-grit stone, it works faster and better. Right after I'm done sharpening, I just carefully rub the stone against the diamond plate for a few strokes, and the surface becomes one uniform, flat colour again. That means that the edges and the center are all on a single plane.

The same thing can be done with the flattening kit that Ben Dale offers as an EP accessory, or with some play sand on your garage floor. Just slower and messier than the diamond plate, but works just as well. Lapping is important to keeping your stones working well, and it's harder to do the longer you let it go, so don't let them get too dished out. :)
 
An excellent method for the beginner is 3M wet/dry sandpaper (320 grit or coarser) on a flat glass used wet!

Using a pencil, make X marks on the ends, edges and middle' (be sure it's a pencil and not a Sharpie)

Soak your stone for 5 minutes, then, pressing lightly but firmly, make figure "8"s on the sandpaper until all of the pencil marks are gone

This isn't a long term solution, but will work quite well indeed until you decide what system you want to use permanently.
 
I have a DMT XC and I'd like to try using it to lap my stock EP stones(I use the SiC powder). Wouldn't it change the scratch pattern that the finer grits(600 and 1000) stones?
 
Theoretically it MIGHT change it for the first couple passes, but any high points on the waterstone are going to break down very quickly. I've never noticed any problems with it, although I can definitely see the diamond's scratch pattern on the stones right after lapping.
 
It sounds like using the sandpaper or diamond plate is the way to go to avoid the mess.
 
Correct, they both work well. Either will do a fine job, honestly, I just like the diamond plate because it's not terribly expensive and it does a much better job of profiling and stock removal than the stock 120 stone.

Here are the DMTs: LINK!
And here are the Atomas: LINK!

The Atoma is a better plate, but almost double the price. :)
 
Komitadjie said:
Theoretically it MIGHT change it for the first couple passes, but any high points on the waterstone are going to break down very quickly. I've never noticed any problems with it, although I can definitely see the diamond's scratch pattern on the stones right after lapping.
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Thanks. Much appreciated.
 
Komitadjie said:
Correct, they both work well. Either will do a fine job, honestly, I just like the diamond plate because it's not terribly expensive and it does a much better job of profiling and stock removal than the stock 120 stone.

Here are the DMTs: LINK!
And here are the Atomas: LINK!

The Atoma is a better plate, but almost double the price. :)
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Thanks for the links. For the DMT stones, would the Extra Coarse (220 grit) be the one to nab?
 
Yup, that'd be the one. It cuts like an angle grinder on steel, and does a very fine job of keeping your waterstones in great shape. Something else you might want to do is after you get it, just go down to the local hardware store and grab four of those little rubber 'feet' like you'd put on the bottom of a ceramic coaster or a desk clock. Stick those on the back out at the corners where they won't interfere with the fit on the EP, and it makes a great bench-stone for heavy profiling work as well. I've used mine a number of times that way to take small nicks out of chisels and things like that.

When you're using the diamond on the EP, the trick is light pressure! Heavy pressure won't make it cut any faster, and can actually pull diamonds out of the plate. The weight of the plate alone is more than adequate to make it cut like crazy, especially since it's twice as wide as the stock EP stone. You'll probably never use your EP 120 stone again after you get it, it just outclasses it in every way, and the 220 does a good job of cleaning up the diamond scratches.

When you lap your stones with it, keep them wet just like you would when you are sharpening. My usual method is to draw a sort of grid of pencil lines very, very lightly on the stone, then just hold the stone and the diamond plate under a stream of running water in the sink, and rub the faces together. Every few strokes I'll flip them end-for-end in my hands to make sure I'm not pressing harder and taking more material off one end or the other. When the pencil lines are all gone, the stone is perfectly flat again and ready for more service. If you do it every couple knives, it will only take three or four light figure-eights against the diamond to have it done, very little material comes off.
 
Someone mentioned the SiC powder from EP. Very inexpensive, and quite effective. :thumbup:
 
I actually just got the aluminum blanks, 2000, and 3000 grit polishing tapes. The area near the choil (the ricasso?) is a challenge to get even on some of my knives. It becomes quickly apparent when you have an uneven grind from the factory. So far I have been able to put a beautiful mirror polish on my Spyderco Tenacious, Paramilitary 2 digicam, and Manix 2. My Sage 1 was able to get a mirror polish, but I can see more micro scratches in the bevel in this knife than all the other mentioned knives. It was the first one I sharpened and I really rushed through it. By the third knife I realized I needed to slow things down and just do it right.

I still need to get that diamond stone to lap the EP stones after all their use. I am going to order that and some 6000 grit tapes this week. This is a lot of fun. I need to get pictures posted.
 
Congrats on the successes! It's really a lot of fun, isn't it? Mirror-polished, frighteningly-sharp edges are just plain fun. :D
 
It really is! Would you happen to know if I got the 6000 grit polishing tapes if I could skip the 3000 grit in the process? Or do you get better results by polishing the edges with each grade?
 
Yes, you can. I consider the 3k tape superfluous.

And when the tape starts to "load up" with swarf, use Mother's mag and alumimum polish on a cloth shop towel to clean it off.

For mounting the tapes, I would strongly recommend getting two glass blanks instead of using the aluminum mounts.
 
I think I'll order those glass blanks when I order the 6000 grit tapes. Does glass give you a harder surface for polishing?
 
It's the flatness on them that really helps more than anything. The glass is completely flat, and does not flex at all. +1 for the Mothers polish, that and semichrome both give some nice results. :)
 
Thank you both for all the helpful advice. I know what I'll be ordering this pay period. :D
 
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