Make a Curved Scraper

I have been carving a few wooden spoons for Christmas presents this year, and I needed a curved scraper to smooth out the bowls on the spoons. I had read somewhere online about making them from handsaw plates.  I would never advise anyone to make a card scraper out of a saw plate with any value.  Handsaws that were made before the days of induction hardened teeth are almost infinitely sharpenable and restoreable, and any quality specimens of that vintage should be kept and used as handsaws.  However, inexpensive handsaws these days virtually all have induction hardened teeth.  This process does exactly what it's supposed to do: it makes the teeth harder so they stay sharper longer.  Handsaws are traditionally sharpened with files, though, and induction hardened teeth are typically at least as hard as a file, rendering them unsharpenable at least with traditional files.  It should be pointed out that you could sharpen such a saw with diamond files made by eze-lap as well as other manufacturers.  But with the saws being so cheap, and the likely slowness of sharpening those hardened teeth, I'm just not sure it's worth it.  Besides, the particular junk saw I had in mind was well past its intended life at probably 8 or more years old.  So, on to making a scraper!

This is the old stanley sharptooth saw:

 I removed the handle.

 Then cut the plate down to a square to start with using a hacksaw

 I ground the teeth off at the bench grinder.

Then marked out the rough shape of the curves I wanted on the steel and cut it out with an angle grinder.

 Then I rounded the corners and finalized the shape back at the bench grinder.

 Next I started removing rust with sandpaper.

Then it was time to sharpen the scraper.  Scraper sharpening is a subject of much mystery and gnashing of teeth amongst many woodworkers, sometimes including myself.  The basic theory is simple, but getting it right in practice can sometimes be frustrating.  I start by squaring the vertical faces on my bench stone.

Then the horizontal faces.  On each face I start out on the coarse side of the stone, then fine, then another finer stone I have until I achieve a decent polish.

And the burnishing is saved for last.  This is where most of the mystery lies, and there are many, many woodworkers out there who have written better tutorials than I ever could on the subject.  The very short version, for those who aren't familiar, is that you first run the burnisher over a vertical edge of the scraper a few times with the burnisher held horizontally applying firm pressure.Then you tilt the burnisher 5 or 10 degrees to one side and make passes focusing on that edge, continuing to apply pressure, and then the other side the same way.  The theory behind all this is that the burnisher is made of exceptionally hard steel, harder than the scraper anyway, and when you push on the edge of the scraper with the burnisher it deforms the metal, raising a hook or burr.  It is this hook or burr that does the cutting when using the scraper.

 Here is the finished scraper, along with some nice shavings cut from the bowl of this spoon.  I have to say this scraper works great - every bit as well as the ones I have purchased.  Go out and make you one!