Wednesday, September 20, 2017

Hollow Grind Calculator

The Perplex of Convex


The discussion comes around every once in a while about wheel diameter to stock thickness and how high a concave or hollow grind will be. Some time ago Bimjo published a web based calculator for this based on Rob Frink's formula. Bimjo's widget seems to have disappeared from the web, but some Wayback pages can be found. Using the same formula I made a new online version.


The idea is that you choose a wheel diameter and some steel thickness and lastly the edge thickness. The calculation is done and you receive the height of the grind. Link is here: http://dcknives.com/public/grind_angle_concave.php

Cheers!

Dan


Sunday, September 17, 2017

KN20 Large Honesuki (garasuki)

This is a larger version of the KN20 honesuki sometimes called a garasuki. The blade is generally a little thicker and longer than a typical honesuki. This one is made from 0.130" AEB-L and features through-tang construction with brass, black paper Micarta and fibre spacers, with the main part of the handle being a synthetic material known as Acrylester Renaissance  #102 . The blade is 175 mm or just shy of 7" long.

West Systems G-flex is used to all the handle pieces together.

Once the stack is all in place the butt is threaded on to the tang screw and a 3/16" mosaic pin is peened into the remaining hole.
Some work on the slack belt really shows how Acrylester is going to turn out. After 400 grit, I took it over to the bench and hand sanded to 1500 grit, followed by some Meguiar's Plast-X plastic polish.










And some photos from the light box...



















Thanks for looking!

Dan