Couple of Questions about Grind Polishing

[bpeezer]

I decided my Emerson EDC-1 needed something special, so I took the PVD coating off the flat grind and started polishing the blade. I was hoping someone had some advice on finishing the polish, and I had one or two questions. Will the polished grind rust easily? I have other D2 blades that are doing just fine, but they aren't really polished. Are there any usage pros or cons to having a polished grind?

For reference, here is the blade.

If you look at it from the right angle, you can easily see that it is still pretty cloudy.

I used my waterstones to remove the PVD and remove the scratches from the grind, and I have just been using my regular strop to polish it. This is after a thousand strokes with the strop on each side of the blade.

 

[zcd]

The polished area will be less prone to rust - there are fewer places for moisture to collect, a smaller surface area of metal exposed to air, etc. You could continue with different grit compounds if you wanted to have it extremely polished..

 

[Obsessed with Edges]

D2 isn't going to rust much anyway (if at all), as compared to any true 'stainless' steel; it's so close to being stainless itself, just a percentage point or less of chromium shy of it. Just treat it like any other stainless blade, and you'll be fine. The one exception is bead-blast; even some well-respected stainless steels will rust with a bead-blast finish, which creates a lot of pores in the surface for rust-making stuff to hold onto. But that's an issue with the finish itself, and not the steel.

As mentioned, polishing the steel, whether it's stainless or not, makes it even less prone to rusting.


David

 

[Cereal_killer]

Wow that's quite the feat for using a strop, I would recommend a power tool (dremel or bench grinder with polishing wheel) with flitz polish next but even by hand on a strop flitz will still work very well.

Great work so far, I don't believe I've ever seen a polished Emerson. Are you doing just the bevel or the flat part too?

 

[bpeezer]

The polished area will be less prone to rust - there are fewer places for moisture to collect, a smaller surface area of metal exposed to air, etc. You could continue with different grit compounds if you wanted to have it extremely polished..

This has all been with 0.5 micron compound, I think it was too much of a jump going from the stones to this compound. This might give me an excuse to buy a higher grit stone to help bridge the gap

D2 isn't going to rust much anyway (if at all), as compared to any true 'stainless' steel; it's so close to being stainless itself, just a percentage point or less of chromium shy of it. Just treat it like any other stainless blade, and you'll be fine. The one exception is bead-blast; even some well-respected stainless steels will rust with a bead-blast finish, which creates a lot of pores in the surface for rust-making stuff to hold onto. But that's an issue with the finish itself, and not the steel.

As mentioned, polishing the steel, whether it's stainless or not, makes it even less prone to rusting.


David

Thanks for the info, that's pretty much what I figured. And I hate bead blast finishes for just that reason

Wow that's quite the feat for using a strop, I would recommend a power tool (dremel or bench grinder with polishing wheel) with flitz polish next but even by hand on a strop flitz will still work very well.

Great work so far, I don't believe I've ever seen a polished Emerson. Are you doing just the bevel or the flat part too?

Just the bevel, I really like the two-tone look. Plus this is my only Emerson (so far) so I want to keep the logo.

 

[Omega Leather Works]

I wouldn't use a dremel for polishing anything as large as that area. A buffer, however, may be the best way.

It's flat ground on that area isn't it? You might be able to use high grit sandpaper, but you'll need to go in both directions, spine to edge, and also ricosso to tip in order to get all of the scratches out.

I agree that that is impressive for just a strop.

 

[bpeezer]

I wouldn't use a dremel for polishing anything as large as that area. A buffer, however, may be the best way.

It's flat ground on that area isn't it? You might be able to use high grit sandpaper, but you'll need to go in both directions, spine to edge, and also ricosso to tip in order to get all of the scratches out.

I agree that that is impressive for just a strop.

Do you know where I could find sandpaper over 3K? The only stuff I've found has a thick spongy backing and is intended for use on cars. I need to avoid the spongy backing to make sure everything in contact is completely flat.

Also, I was doing some research on the cloudiness left by waterstones. It seems that I can mitigate the effect by using the stones relatively dry as long as I am careful to avoid loading. I'll do some experimentation (and ruin all the work done by my strop so far )

 

[bpeezer]

I went ahead with some more experimentation, and it looks a little bit better than before. It'll have to do for now, I'll probably try to pick up some flitz in the near future and see how much better that makes it.

 

[ryxlyx]

I've not found (locally anyway) s'paper over 3000.

If you want a crisp intersection at the top of your polished blade face where it meets the blade flat (I can see a bit of blurring towards the front already) I would recommend you don't use any kind of rotary-- you will blur it further. You have to be careful polishing D2-- the carbides are so huge (hence the "toothy" edge) that if you press too hard you will literally pull them out of the matrix ("plucking the carbides")-- I've done it. I've got pixes of a D2 blade that looks like craters of the moon. I ended up flatsanding back to 3000-- I like the uncratered look better, directional 3000 passes for polish unless the light hits it right (as you would know).

 

[Omega Leather Works]

If you need a finish with super high grit paper you might look for 3M micro mesh at your local hobby store.

In any case, your knife is looking good!

 

[bpeezer]

I've not found (locally anyway) s'paper over 3000.

If you want a crisp intersection at the top of your polished blade face where it meets the blade flat (I can see a bit of blurring towards the front already) I would recommend you don't use any kind of rotary-- you will blur it further. You have to be careful polishing D2-- the carbides are so huge (hence the "toothy" edge) that if you press too hard you will literally pull them out of the matrix ("plucking the carbides")-- I've done it. I've got pixes of a D2 blade that looks like craters of the moon. I ended up flatsanding back to 3000-- I like the uncratered look better, directional 3000 passes for polish unless the light hits it right (as you would know).

Ooooh thanks for the heads up, I had no idea that could happen. I was planning on finishing with the dremel, I'll just finish up by hand

If you need a finish with super high grit paper you might look for 3M micro mesh at your local hobby store.

In any case, your knife is looking good!

Thanks and I'll look for some of that micro mesh this weekend.