Rehabilitating Old Chisels - Part 1

by Bob Smalser

I was in the market for a large framing chisel on Ebay and wound up with a package deal for 30 bucksan old Stanley 5C Type 16the Lakeside 2 Framing Chisel I wanteda beater chisel with a mangled tangand an old coopers shaping chisel:

  This article will deal with the two framing chiselsthe coopers chisel was usable as is with some cleaning and sharpening, and the plane Ill cover in another article, although Ill rehabilitate them together. These will be put back to work as users, like all my toolsrestoration of collector items is another subject.

  For this article, Ill purposely use only the minimum tools and techniques necessary for a first-class joband all the work done in a crude, temporary 12 by 12 shop. My intent is to provide a model for newcomers to the craft who will benefit greatly from acquiring older but high-quality tools in need of a hug for very little moneyand putting them back into service without a lot of machines and fancy gizmos you dont have yet. Moreover, with enough practice rehabbing old tools, making new ones like in other articles Ive written, and doing traditional joinery for your workbenches and other shop necessitiesby the time you create for yourself a nice workshop, you may find you no longer feel a need for all the trendy doodads shilled at you weekly.

  I use a large, 8 gunsmiths pedestal buffer-grinder for most of my grinding and polishing chores, but a smaller 6 bench grinder will also work fine.

  First, I use a soft steel wire wheel to clean all metal parts thoroughlythe coopers tool has been cleaned in the shot to the left.

  Next, I treat them with a phosphoric acid solution (right) available at home improvement chains to kill any remaining rust. This is the functional equivalent of using an electrolysis solution for those not so inclined. The phosphoric acid is allowed to sit over night to work. The next day, the black oxide rust residue is removed with the wire wheel in preparation for buffing and finish laterwe need to do some rough grinding and make and mount the handles, first.

  The treasure of the lot is the one in the worst shape; of coursea Robert Duke Diamond Brand firmer-style chisel of lovely, glass-like cast steel. It had lost its handle ages ago and probably served to cut the heads off nails with a large, ball peen hammer in its old age. The socket tang was badly mangled with the remnants of the old handle remaining in the void. The tang was returned to its original form by drilling and filing the socket mortise, and grinding off the metal extruded on the outside.

  Fortunately, there was enough socket mortise remaining to use or I would have required the services of a neighbor I trade work withand his TIG welderto build it up. Using heat-sink paste and wet rags, I might have been able to build up the socket with my torch welding setup without ruining the blades temper, but it would have been riskier, and Im not near the welder my professional neighbor is.

  As the blade was badly chipped and had lost its bevel, grinding was required. While I have a jig for this, I rarely use it any more and freehand the 25-degree bevel using lots of waterturn that blade edge 600-degree blue and it has lost its temper and all the blue must be ground awayand I use a square and protractor to check my progress.

  As the other blades are in better shape, and I dont prefer to leave the bevels of heavy chisels and slicks with a hollow grind (although not importantmerely personal preference), I finish the grinding stage for my 25-degree bevels on the belt sander chucked in the Workmate. I use 60, 80, 100 and 150 grits lubed with WD-40 and lots of water, checking my bevel angle and edge with protractor and square as I go.

  Final honing of 25-degree bevel and 30-degree secondary bevel will come later.

Now on to Part 2