Burnish this

Last year sometime, James posted a review of a birdcage awl by Chris Black on his blog The Daily Skep. I wasn’t in the market for an awl at that point, but Chris makes several other tools and sells rehabbed old user tools as well.  If you’re in the market for something, check out what he has on craigslist.

While I didn’t need an awl, I did need a burnisher.  Craig has some nice ones that use a hardened M2 tool steel bar.  A quick hop over to the AZO Materials website, which is a great place if you ever need some quick and dirty material properties, told me that the bar should be close to 60 HRC in hardness.  That’s pretty hard.  So I ordered one.

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It’s a great looking tool.  The handle is nicely turned and the ferrule is the right size to balance the transition. So, instead of using it, I went right to the lab and put it into a hardness tester to see if the hardness was what it was promised to be.

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The hardness of this burnisher was 61.1 HRC.  That’s hard and should be able to turn a hook on almost anything.  No where near as hard as carbide (90 ish HRC), but more than enough to do the trick.  I’ve used it now to sharpen a few scrapers and it just works.  If you have some sort of crazy hard scraper it might not work, but the old bahco and the two cherries card scrapers I have turn a hook right away.  So if you need a burnisher, you would be hard pressed to go wrong with one from Chris.  Get it here.

As a postscript, I do not suggest hardness testing your burnisher.  The diamond indenter leaves a little raised ridge around the indent that can cause trouble when you’re burnishing. I had to sand it smooth after testing.

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