2.22.2012

Swan Necks?

I really enjoy timber framing tools.  Maybe my fascination has something to do with the enormous, almost novelty size of timber frame tools compared to the chisels and gouges I typically use.  This might be akin to my alternate fascination with tiny espresso cups... okay, I just like to pretend I'm a giant.

Fortunately for me, H.O. Ibbitson & Co. and Richard Melhuish Ltd. forged some wonderful, similarly designed swan neck mortising chisels a long, long time ago.  These were one of those finds that had me all giddy because I had been looking for one to restore for my friend as a Christmas gift, and here were two together!
H.O. Ibbitson & CO. Swan Neck Mortise Chisel

Richard Melhuish Ltd. Swan Neck Mortise Chisel


























I know several manufacturers made swan neck chisels with this design including Sorby, but I had never seen one in person.  These are some tough looking tools.  They have a gorgeous fish hook style business end, and due to their age they are made of some wonderful steel.  They needed some pretty serious cleaning when I got them, but with a little elbow grease, Sandflex Rust Erasers, Evaporust, and patience they came out looking beautifully patinaed.  Both makers marks are still very visible and were relatively easy to clean.
A Surprisingly Light Amount Of Rust In The Socket
Melhuish

I suspect the fish hook/ladies boot design came about for several reasons.  First, they were likely easier to forge with a large mass toward the thin crescent shaped cutting edge, and second, the large mass gives a striking edge and reinforcement against the prying motion used when cleaning out deep mortises.  Whatever the original intended purpose, it gives these tools a very serious demeanor.  Just holding one made me feel tougher, and I need all the help I can get.

Both wooden handles needed some attention as well.  The wood on both had the obligatory white paint drips and were black and filthy with use.  I didn't want to sand them because I'd lose any original finish underneath, so I tried just a little gentle hand soap and warm water on a rough cloth.  This was apparently all they needed as they cleaned up perfectly.  I applied some Renaissance Wax to both the steel and the wooden handles and they looked full of life again.  I was really happy with this restoration


After Cleaning But Before Wax And Initial Sharpening
Sharpening these things was another story altogether.  Because of the hooked end and consistent curve throughout, I had to determine the bevel angle tangential to the tip of the blade.  I started by wearing a flat spot as close to the blade edge as possible in order to not negate the nice curvature of the blade.  Then I marked out a distance on my sandpaper which gave me two points of contact, one on the edge of the glass and the other on the bevel edge held at the correct sharpening angle (see diagram below).  These were side sharpened, meaning I moved them back and forth parallel to the edge of the glass and sandpaper as opposed to drawing the bevel  back and forth.  This method allowed me to maintain a consistent angle of attack on the bevel.  Really, the diagrams speak to this better than my half-assed description.


I also did something I don't usually do, I put a micro bevel on this tool.  I wanted a really steep cutting angle but I didn't want to sacrifice a ton of material on the bevel side to get that angle.  These had been previously sharpened at a rather low angle for such a heavy use tool.  The micro bevel is as close to 35 degrees as I could hone freehand but the primary bevel is more along the lines of 25-28 degrees.  I will say, however, that I was able to put an amazingly sharp edge on these tools (Soon my ego will require its own blog).  The beautiful edge was a combination of two factors, in my humble opinion.  The first factor was being very meticulous about my sharpening and honing methods and the angles I was trying to achieve.  The second factor was the beautiful steel these old tools were forged with.  The steel that comprises these two chisels was actually rather easy to abrade, however, I tested these edges and they remained razor sharp through some relatively heavy abuse.

Typically these types of tools are used in a prying motion so that the tip pinches off that stubborn little piece of wood in the bottom corners of a mortise, however, these can also be struck and used more like a regular chisel if the situation calls for such a maneuver.  Once again, see terrible illustrations.
In A Narrow Mortise The Chisel Can Use Itself As Leverage

In A Wider Mortise The Chisel Can Be Used To Scrape
Or It Can Be Malleted On The Heel To Remove Stubborn Material
Now if I could just find those extra tiny espresso cups, I know I put them somewhere and I need some coffee!!!

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