Wednesday, December 3, 2014

Knives - sharpening

  This afternoon I went down to my shop with the purest of intentions. I was going to clear away some tools, move a standing bench around a bit and get serious on a couple of Christmas gifts that need attention, if they are going to qualify as gifts for this Christmas.

 First however I needed to spend a couple of minutes sharpening a knife that I'd brought home from the communal cutlery drawer at the Ancaster Seniors Achievement Centre.  If you have ever been connected with a community kitchen you know the sort of knives that are in that vast drawer of castaways.  Worse than the appallingly bad knives is the way that the knives are treated.  Our kitchen has two stainless steel work tables and a couple of 'glass' cutting boards.  Sadly, even when I sharpen a knife on Tuesday, by the following Tuesday it will barely cut vegetables.

 Today I brought two knives home to sharpen. One is a standard paring knife, of actually good quality, though very very dull. Sharpening this knife is no big deal, trying to find a place to hide it so that it will be sharp when I want it next Tuesday is another thing.

 The second knife is one of those T.V. brand super knives with a serrated blade. 

 I have used these kitchen knives before and they aren't too bad, but the steel is soft and the edge turns over easily. (especially if you cut on a glass cutting board or a stainless steel work table)

 The edge on this knife was rolled over to the point that it even the serrated edges were bent over. I suspect that is why some thoughtful soul generously donated this knife to our kitchen. Well, surprise, a little bit of work with two needle files and this knife is as good as new.

  First I used a small flat file to grind the hook on  the non-serrated sections of the blade. I clamped the knife to my bench and quickly filed away the rolled edge.  Second, I used a rat tail needle file on the serrated section, I think a triangle file would also have worked to clear away the rolled edge. 
  This type of knife has shiny stainless steel which isn't very hard so once the blade is clamped down it was easy to sharpen. These knives also have a single bevel blade which means there is really only one side to worry about.  Next time you are at a yard sale and one of these is for sale for $0.25 you can bring it back to life for cheap and very little time. It would make a really good picnic basket knife, sharp but cheap.

 The other knife that distracted me from my goal was this Game of Thrones, style letter opener.  I picked this beast up at the Woodstock Wood show last fall.  A local smith had been beating mild steel into various shapes, one of which was knives (?) like this one.  He didn't have the tools to make any effort toward forming an edge on the knife, it was nearly 3/32 on the narrower side, not really an 'edge' at all.

 Since I was putting things away and moving my bench around I decided to sharpen this knife to the point that it could be used as a letter opener.  Since it is mild steel it won't hold an edge very well if used like a real knife, but a letter opener won't tax it too heavily.

 I began forming the blade by grinding a bunch of steel away using my bench grinder.  The only thing that you have to remember when using a bench grinder is to not let the steel get too hot. I keep a bottle of water handy and keep the steel cool. Once I'd sort of ground the basic shape I clamped the blade to my bench and did some work with a course then finer file.  

  The last stage was to use my low speed wet stone grinder to get to the stage that it could then be sharpened on my Work Sharp. Once I got through all the stages the blade was really quite sharp, but I know that the edge will roll almost instantly if I try and cut anything tougher than a banana or an envelop. That doesn't matter because it was just a distraction and a bit of fun.  

  Now I have got to get back to serious wood work, there is a boat and some blocks that need to be made before Christmas.  

cheers and a merry ho ho.


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