Spinoff question - sharpening as comparison to sanding wood

[tuffluv]

spinoff from here: http://www.bladeforums.com/forums/showthread.php/1281235-Why-sharpen-to-such-high-grits


When sanding wood it's standard practice to start at a low grit and work your way up through higher grits in sequential steps being sure not to skip grits.

Is this sequential sanding necessary when sharpening knives?

I ask because I've seen some people sharpen at 325 grit then 1200, then strop. Even Murray Carter has his 1000 grit stone followed by a 6000 grit stone.

 

[Jason B.]

Depends on the abrasive,

The 1k and 6k waterstones are a large gap regardless of how we look at it but the abrasive cuts aggressively enough that unless the steel is very hard or wear resistant its not that big of a jump. Some sharper and harder abrasives Found in higher quality stones makes jumps like this a common thing. Take the Shapton Glass stones for example, they recommend basic sets like 500-2000-16,000 all the time.

It's not always about getting all the scratches out either, some of the best cutting edges are a mix of polished and toothy the 2000-16,000 jump of the Shaptons or the 1k-6k of the Kings are a perfect example of this.

The only time a tight grit progression is needed is when you want a flawless surface.

There was a time when I polished every edge in lust of the shine, eventually reminding myself that my goal was the edge and not its shiny flat sides.

 

[Obsessed with Edges]

A lot of my favorite edges come from honing with a ~320-grit SiC stone (or similar sandpaper) or a 'Fine' diamond (~600/25µ), followed by stropping on denim with some 2-5µ white rouge compound. It just seems to work well for me, and I've not had much reason to go further with the finishing. They cut like demons, and I don't need to fix what ain't broke in a quest to make it look 'prettier'. To me, the real beauty is in the cutting anyway.

And even with wood, it comes down to what it's being used for. This last week, I refinished some rustic outdoor furniture at our place using some 60-80 grit sandpaper on an orbital sander, followed immediately by oil-based stain/sealer. Looks great.

Edit:
I just finished resetting bevels on a Victorinox paring knife, using a Coarse DMT (325 mesh/45µ) and following with the 2-5µ white rouge on denim, as mentioned above. That's made for a wicked-toothy & effortless slicer as well. So, whatever works...


David

 

[tuffluv]

Thanks for the info.

 

[8steve88]

It is similar in that every progression takes out the scratch marks put there by the previous sanding/sharpening, repeat until satisfied by the surface or edge.