While chopping mortises for the plant stands, I thought I'd use a mortise chisel I came across at a garage sale not too long ago. Prior to that my, mortising chisel was my standard Irwin bench chisel.
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| 1/4" Irwin bench chisel and ~1/4" Ulmia mortising chisel |
These two chisels are very different from each other. Aside from the obvious difference in length, the Ulmia has a much thicker blade, a shaped wooden handle (as opposed to the plastic handled Irwin) and the blade has a tang while the Irwin is a socket chisel. Both bevels are ground to about 25°, with a microbevel of about 30°.
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| The edge profiles |
The difference in length is quite significant.
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| That's one long chisel |
The length of the mortise chisel comes in handy when it comes to keeping the chisel vertical by sighting down the piece being mortised.
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| Much easier to tell if you're off vertical |
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Can still use this method with the Irwin,
but any deviation from vertical is not as pronounced |
I timed a few mortises, using either chisel in turn. They were both freshly sharpened. There really wasn't any difference in how long it took to chop a mortise. But look at the cutting edge of the Ulmia after just a few mortises.
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See the white reflection at the end?
That's one dull chisel |
I don't know about these Ulmia chisels. Maybe the steel is bogus. Maybe there was a hard spot in the oak that I mortised that was tough on the edge. Maybe it was user error.
I really like the advantage that the length gives. But if the steel is not going to hold up to the stresses of mortising, it might not be worth it.
FLASH! This just in! Thought I was done with this post, but just today I received in the mail a mortise chisel. I had no idea this was coming my way.
Ralph, I don't know what to say, but thanks. I owe you big time for this.
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| It's a 3/8" (or a tad over 3/8") "pig-sticker" from I. Sorby!! |
Holy mackerel, this thing is beefy! Look at that handle. I think it'll be able to take a bit of pounding. And here it is compared to the other two chisels.
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| The Ulmia chisel looks like a skinny runt by comparison |
All I can say is, wow! Can't wait to sharpen this chisel up and try it out next time I need a 3/8" mortise.
Maybe I should have entitled this post "A Tale of Three Chisels".
