Poltava 30K Metallic CBN Review.

[wade7575]

As most of you know I really like the Metallic CBN stones and the highest grit I had up until this stone was the 15K which has been a really good stone for me.

The 30K I got was level but the surface had a texture to it sort of like spackling or The Rock frying pan's they are level but they have a rough surface,the problem with stone is the copper tin matrix is a bit rough.

The 30K stone removed metal but it didn't make the edge any sharper,I'm going to try and flatten this stone to see if I can smooth out the surface of this stone and get better result's.

I'm not posting any picture's of the stone because when I tried to get a picture of the surface of the stone my camera wouldn't pick up the the surface finish but I'm posting picture's of the edge of the knife.

I sharpened a Manix 2 in M390 with stone and didn't find the result's to be to my liking.

 

[Diemaker]

So what is the micron size? That is awfully fine for that type of bond. I know how you "dress" them but how do you flatten that stone?

 

[wade7575]

It say's it's .5 micron on the blank,I haven't had to deal with this problem before but a friend of mine in the states who got a metallic CBN stone after I got mine told me that he used a flat peace of glass and used sand paper then silicon carbide powder to get as much of the texture gone then use ferric chloride.

I wasn't to sure about my 15K stone when I got it and thought it may just be a waste of money but from from 1K to 15K I have had really great result's with that leave an edge that is fairly free of burr's if you make sure to remove them once you get to the 400 grit the rest don't seem to form a burr and if they are you can't feel it with your finger nail.

 

[tiguy7]

I wouldn’t think that SiC would scratch CBN. A Diamond dressing stone might be more appropriate.

 

[UncleBoots]

This is seriously fascinating. Partly because you bought this really interesting super-fine stone and are needing to do surgery to make it dance. But partly because I have the 8K and 15K of these stones, and have been neglecting them, bailing out after 2K or 4K to strop. What am I missing out on by not proceeding to the higher grits?

 

[wade7575]

I wouldn’t think that SiC would scratch CBN. A Diamond dressing stone might be more appropriate.

The CBN is way harder then the Sic and the worst it is going to do is scratch the surface a bit and once the stone get's used it's going to settle back in.

 

[wade7575]

This is seriously fascinating. Partly because you bought this really interesting super-fine stone and are needing to do surgery to make it dance. But partly because I have the 8K and 15K of these stones, and have been neglecting them, bailing out after 2K or 4K to strop. What am I missing out on by not proceeding to the higher grits?

I have found with my 8 and 15K stones that they leave an edge that's a very fine toothy edge that give's my edge's the best of a toothy and polished edge more then any other stones out there,I'm not saying it's perfect but it's just a great working edge that's also toothy and fine.

I mainly just wanted to see what the 30K would be like and what it's effect's would be like and so far I don't like it at all,I also like how much faster the Metallic CBN's cut then any other stone including the Venev Diamond stones and how much faster I can put an edge on a knife with these stones.

 

[bgentry]

That blade appears to be chipped in at least 4 places in the last half of the blade leading to the tip. Or maybe it's "stuff" stuck to the blade?

Brian.

 

[sickpuppy1]

Another down by the choil too, but I’m assuming it’s a user and he didn’t want to take it that far.

 

[wade7575]

It's just metal swarf that's stuck to the blade that I didn't get all off,I took the picture's pretty much right after sharpening and I normally like to clean the blade off really good for a review,plus the lens on my isn't helping me at all and I need to get a better lens for macro photography.