Martyfish's Knife Makeovers (Thinning, Refinishing and Handle Making)

[naptight]

@Martyfish looks so comfy. Is there a reason to round the edge at the heal like this?

 

[Choppin]

Toyama Makeover Part 1: Reprofiling, Rounding and Refinishing

I picked up a 210mm Toyama nakiri recently and liked it so much that I decided to give it a facelift. It performed great out of the box, but there were several things that I wanted to improve upon, namely:

• Rounding sharp or broken edges (done )
  Evening out the profile bit, so that the curvature was more gradual and symmetrical (done )
  Removing some material from the tip and choil, so that they intersected the spine perpendicularly (done )
  Giving the blade a nicer polish (in progress)
  Replacing the handle with something a bit more exotic (still to come )

The blade also had some minor imperfections that I wanted to correct, such as:

• Deep residual scratches in the core steel on the left side of the knife (still to come )
  Pitting or a similar surface imperfection in a small, localised area of the nickel layer between the core and cladding (still to come )
  Deep residual scratches in the cladding on both sides of the knife (done )
  An under-grind at the heel on the right side of the knife (still to come )

I'm about half way through at the moment, but the most tedious work is out of the way.

Rounded Choil

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Rounded Spine

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Rounded Tip

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Blade

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Looks great! The new profile is very flattering.

Speaking from experience, removing scratches from Toyama core steel is no fun lol... it's faster on stones, but the original grind isn't flat on the core steel. I ended up using sandpaper but it took some time.

 

[Martyfish]

@Martyfish looks so comfy. Is there a reason to round the edge at the heal like this?

Thanks, it's a big improvement on the comfort front. Rounding the edge at the heel stops it from snagging on tea towels, sandpaper, makeup pads, careless fingers, etc. Most of the above are relevant for polishing with non rigid materials (sandpaper, diamond pastes, etc.) rather than cooking, but it's also nice to not snag the heel on tea towels.

Looks great! The new profile is very flattering.

Speaking from experience, removing scratches from Toyama core steel is no fun lol... it's faster on stones, but the original grind isn't flat on the core steel. I ended up using sandpaper but it took some time.

Thanks! I did the scratch removal today and I ended up using stones. I prefer sandpaper for a lot of applications, but find it too slow and inconsistent for polishing hardened steel. Thankfully all of the scratches were on the left side of the blade, so I could go to town without having to worry too much about maintaining convexity. Even with the stones, it probably took me an hour to get it up to a 3k finish, so I don't want to imagine how long it would take with sandpaper

 

[Martyfish]

Toyama Makeover Part 2: More Refinishing

I removed all of the deeper scratches in the core steel and cladding and managed to get out most of the pitting or whatever it was at the transition between the core steel and cladding. The polishing stages for both the core steel and cladding are described below:

• Cladding: P120 grit sandpaper P180 grit sandpaper P320 grit sandpaper P600 grit sandpaper P800 grit sandpaper P2000 grit sandpaper an F360 grit silicon carbide powder and mineral oil slurry applied with P2000 grit sandpaper uchigomori finger stones uchigomori finger stone mud applied with 0000 steel wool an F360 grit silicon carbide powder and mineral oil slurry applied with 0000 steel wool
• Core: Naniwa Pro 800 Naniwa Pro 3000 10 micron diamond polishing compound applied with a cotton makeup pad

I'm really happy with the polish and the knife is well on it's way to being finished now, with just the handle remaining.

 

[Martyfish]

Toyama Makeover Part 3: A Mostly Finished Handle

This time I went for a stacked birch bark / bog oak handle with a brass front cap and this is a rough finish directly off of a P120 grit belt. All that remains it taking it up to a higher grit and giving it some oil. Although it looks a bit lifeless at the moment (with the coarse finish and no oil), the geometry and proportions are really nice.

 

[Martyfish]

Toyama Makeover Part 4: A Finished Handle

This is the finished handle and I think it's really stunning. I especially like the contrast between the satin and highly polished areas on the brass front cap. Interestingly, the birch bark did not react well to polishing, because while high grit sandpaper made it smoother, it also caused a lot of saw dust from the bog oak and brass from the front cap to become embedded in the bark, which made it look grey, dirty and just kind of crap. I had to take it back down to P320 grit, which is where the material removal rate was quick enough to prevent any major surface discoloration.

If I'm being really critical, the facets could be a bit more even, but it's honestly not something that I actually noticed until taking a close look at the pictures, so it's safe to say that it's not something that is very apparent to the naked eye.

Side view (barely perceptible taper):

Top / bottom view (light taper):

A close-up showing the brass front cap and birch bark:

Front view + tang slot:



View from the back of the butt:

Detailed dimensions are below (mainly so that I remember them in the future). Please note, that this handle is for a chonky 203 x 63mm Toyama nakiri and a handle of this size would look out of proportion on a more regular sized 180 x 50mm nakiri.

Length

Total: 135mm
Ferrule: 35mm
Butt: 100mm

Rectangular cross-section prior to applying the facets

Front of ferrule (W x H): 18 x 24mm
Back of butt (W x H): 22 x 25mm

Facets

Front of ferrule: 6 x 6mm
Back of butt: 7 x 7mm

 

[enrico]

Props to you for sanding all that stainless down. By hand as well? Looks great

 

[Martyfish]

Props to you for sanding all that stainless down. By hand as well? Looks great

Thanks. Yeah, all of the polishing on the blade was done by hand. Close to the textbook defenition of masochism haha.