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Sharpening tips for your woodworking tools
As with any type of machine sharpening, it's important that you be careful not to overheat the steel of the chisel during sharpening, as this will draw the temper out of the edge. Once the edge turns blue/black, it's too late. The steel will be permanently softened ...and that means that it will no longer hold as good an edge for as long. Here are three ways to prevent this problem:
Keep a bucket of water nearby on the floor to cool the steel as you sharpen it, dipping your chisel into it frequently.
Always use a medium or coarse grit Sanding Disc at the slowest RPM.
Lessen the pressure and actual time of the grinding as you work the bevel down to the cutting edge of the steel. Some craftsmen avoid grinding to the extreme edge, choosing instead to hone it with a benchstone only.
If you'd prefer to try and make your own shop-built Jig, just follow the plans shown in Figure 2. The dimensions on the example Jig are for grinding a 30-degree cutting edge (15-degrees on each side of the bevel) with a 15-degree Skew angle. You'll have to make a different block to suit each bevel angle you're after. Just remember,
it must be a Jig with two separate positions for grinding both sides of the Skew.
When using the Jig, be sure to mount it securely to an auxiliary Miter Gauge Extension Face. Then clamp the entire assembly to the Worktable and position the Table with its edge 2" to 3" away from the face of the Sanding Disc...so the Skew's long handle will clear everything during grinding (See Figs. 3 & 4).
Fig. 3 Grinding first side of 1" Skew. Jig clamped and extended so Skew handle clears edge of Worktable. Feed toll toward Disc slowly and firmly.
Fig. 4 Grinding second side of 1" Skew. Adjust clamping jig so that you use the Disc Sander surface equally. Avoid overheating tool steel by backing tool off Disc frequently and dipping in water.
A simple Jig for the 1" and 3/8" Gouge can be made from a 2" x 4", cut at a 30-degree angle (providing that's the bevel angle you want). Clamp it to your Miter Gauge Face and the Worktable with a 3/4" thick piece of scrap stock underneath the Jig. This scrap stock should extend enough to hold the Gouge handle and ferrule off the surface of the Worktable during grinding.
Fig. 5 Grinding Gouge. For this first step in a two-step procedure, firmly and slowly push the tool into the Disc with clockwise rotation following angle of jig and traveling through half of the Gouge bevel contour.
Be sure to do your grinding on the upper portion of your Sanding Disc (See Fig 5).
Use a two-step procedure: With the concave side of the Gouge flat down on the Worktable, hold it firmly with both hands and push it in, making contact with the Sanding Disc the entire time. Rotate the tool smoothly in a clockwise motion around half its contour. To hone out the grinding scratches, hold the Chisel steady on the edge of wide piece of scrap stock clamped in a bench vise.
Fig. 6 Honing Lathe Chisels. Lubricate the benchstone and rub it on the Chisel bevel as you hold the tool steady.
Rub a benchstone across its bevel as shown in Fig 6. You might be surprised by the control this method provides. When doing Gouges, use a Curved Gouge Slipstone.