Four tools you can make
Above: Workshop made tools, left to right: carbide burnisher, birdcage awl, micro chisel and marking knife.
Words and photos: Troy McDonald
Diagrams redrawn by Graham Sands
Toolmaking is something that just seems to come naturally to woodworkers. In fact, it’s hard to imagine anyone could progress fully in the craft without eventually making some sort of custom tool or jig.
The tools presented here are useful to have and not difficult to make. Simple lathe turned handles are shown however
if you don’t own a lathe then I’ll show you how to make something just as functional with a few basic hand tools.
Photo 1: The materials required are as simple as those shown in the photo. Small timber offcuts for the handles, brass tube for ferrules and tool steel for cutting edges. Old scrapers, router bits and files can be repurposed into functional tools
with specific applications.
Try to select hardwood for the handles and the denser the better. The tools shown above have handles made of mulga and tallowwood. The handle patterns shown in fig.1 are taken from traditional designs.
Of the four tools discussed here, I consider the marking knife the most important. A wonderful range of beautifully made marking knives are now available, but many have a single bevel spear point blade that I personally find awkward to use.
Woodworkers are a diverse bunch so please be your own judge, however, having used a number of knives over the years I keep coming back to a simple double bevel blade (fig 2). Many will argue that a double bevel knife will introduce error when run up against a straightedge or rule but in my experience the error is so minute it can be completely discounted for thin blade knives.
To eliminate this error entirely, you simply tilt the blade a few degrees in use such that the bevel aligns with the surface you are using to guide the knife while marking. Single or double bevel, the one attribute of a knife I find most important is the overall shape of the blade. And this is why I strongly prefer the double bevel blade. Knives with a single bevel force you to either have two knives in a left and right hand version or alternatively a spear point shape that lets you combine two knives into one (fig 2).
The double bevel, however, allows you to move to a traditional bear claw shape blade that I find makes the knife so much more functional when marking in tight spaces such as between dovetails. Again, I’ll caution that this is my personal preference but my only request is that you consider a standard double bevel blade before believing that a single bevel blade is the only option
to allow accurate marking out. Like so many things in woodworking, simple designs often prove to be the best. So much for the design, how do we go about making one?
Photo 2: The handle design for the marking knife allows it to be held pencil like and is taken from the antique glass cutter shown lower left in photo 1. The shape sits comfortably in the hand and allows for accuracy in use.
Select a hardwood blank around 20mm square of dimensions shown in fig.1 and rough it to round. Cut the tenon to final diameter but do not drive the ferrule onto the tenon. Drill the blank to a depth of 40mm with a 1/8" drill. This hole will allow the blade to be glued in place should it be required.
Photo 3: With the blank removed from the lathe use a fine handsaw to cut vertically down the tenon. The kerf will provide support to the blade and needs to be cut with a saw that results in a firm or tight fit. With the saw cut complete, drive the ferrule into positon and remount the blank on the lathe between centres for final shaping.
Photo 4: The detailed turning can now be completed with skew or gouge to the dimensions shown in fig.1. The final shaping should be the small bead defining the end of the handle.
Photo 5: Finish sand to 320 grit before parting off the blank.
Photo 6: Selecting and shaping the blade is the last step in the process and any sort of scrap tool steel will be just fine. Again, my recommendation is to keep it simple. These knives don’t need to be made from carbide or any special tool steel alloy. In reality the blade will do very little work as it will be required to simply sever surface wood fibres.
Steel sourced from old scrapers, large bandsaw blades or even repurposed stainless steel kitchen knives will all work perfectly well. For this knife I wanted a thin blade suitable for marking dovetails so I chose to cut the blade from an old scraper that was around 0.8mm in thickness. You can make knives with different thickness blades should you have a special purpose such as this. For general work a thicker blade up to 1.5mm in thickness would be preferred. Mark out the blade shape and cut it from your blank with the aid of a cutting wheel mounted in something like a Dremel.
Photo 7: Before sharpening, trial fit the blade into the handle and finetune the shape to allow a tight fit into the saw kerf within the ferrule. If the fit is loose you can use epoxy to secure the blade.
Photo 8: The blade can be brought to final shape at the grinder before grinding the double bevel at something like 25°. Hone the bevel on your preferred stone to fully prepare the blade for use.
Photo 9: All that remains is the shaping of two flats on the body of the knife where your finger will rest during use. The original pattern I based this design on had these in place and they add surprising stability in use. They also allow you to feel the orientation of the blade without looking. I used a bobbin sander and held the knife blade against a block cut at an angle of 75° to ensure the facets were in correct orientation to the blade.
Carbide burnisher and micro chisel
The burnisher shown is of carbide with adequate hardness to turn an edge on the hardest of cabinet scrapers. You can purchase polished carbide rod, however it’s expensive and with a little effort you should be able to find plenty of carbide in the form of discarded tooling. Manufacturers that perform CNC cutting provide good options for repurposing carbide cutting tools.
For this example I have chosen an old 6mm solid carbide router bit. The third tool to be discussed here is the micro chisel also shown above which was made from a broken triangular file. Custom tools like these are indispensable for a multitude of tasks such as cleaning out dovetails and recesses for inlay or banding. Old drill bits, metal taps, files and allen keys can all be turned into effective tools after a few minutes on the grinder followed by honing on water or oil stones. The handle design is shown in fig.1. If you don’t have access to a lathe then a simple alternative is also shown below.
Photo 10: Select a suitable hardwood blank and rough turn it to a cylinder. Mark out the length of the handle and with both parting tool and calipers reduce the blank to the sizes required by the pattern and ferrule.
Photo 11: With the ferrule diameter roughed to size the final fitting can be accurately done by following a few simple steps. I use the method outlined by Richard Raffan in AWR#44*. First, ensure the tenon is cut longer than required for the ferrule and then cut a chamfer or taper on the leading end. Fit the ferrule over the chamfer and mark the inner diameter via twisting the ferrule into position to leave a burnished mark. Reduce the tenon to the diameter marked by the burnishing on the chamfer for a guaranteed firm fit. Use a skew to cut a square shoulder to ensure the ferrule sits tight against the remaining blank.
Photo 12: Again with the skew, trim a small taper on the tenon end which leads into the shoulder. This important step ensures that as the ferrule is driven into place, any waste that curls up ahead of the ferrule can be removed before it becomes trapped against the shoulder preventing a clean fit. Drive the ferrule into position watching for and removing any waste that is cut from the tenon. Use an extra ferrule to guide the last few taps to ensure it is firmly seated on the shoulder.
Photo 13: Run a suitably sized drill through the ferrule end of the blank to the required depth to take the tool shaft. Finally return the live centre to position before final shaping with skew or detail gouge and finish sanding.
Photo 14: Drive the tool shaft into the handle for a
tight fit. In the case of the micro chisel, the file teeth are removed on the grinder on the surface that will become the chisel back. The bevel is then ground ahead of final honing.
A birdcage awl is one of those tools you’ll wonder how you lived without once you have one in your kit. It differs from a standard awl in that the cutting blade is square in cross section and sharpened to a pyramidal point as opposed to the conical point used on a typical awl.
It’s the pyramidal shape that sets the birdcage awl apart. Where the standard awl has a tendency to split the timber, the sharp edges of the birdcage awl actually cut the timber when turned and will effortlessly drill a hole suitable for small screws or centre marking. Their name comes from the fact that they were initially designed to drill the hundreds of small holes that were required to house small diameter dowels in the making of birdcages.
Photo 15: Select a hardwood blank around 50mm to suit the pattern shown in fig.1. Follow the guidelines provided above for the burnisher handle to mark out the transition points in the pattern and fit the ferrule. Run a drill through the tenon to a depth of 40mm to suit the size of your selected tool steel shaft. With a detail gouge, bring the handle into final shape and sand before parting off. Fit the tool steel blank and then polish with thin shellac.
Photo 16: Grind the facets of the awl with the help of a fence clamped to your grinder. Ensure the tool is kept cool through frequent quenching in water. The fence should be positioned to establish a facet angle of approximately 10°.
Photo 17: The finished tool showing the facets straight from the grinder. A steeper secondary bevel can be established on a coarse stone to provide increased strength to the tip making it less prone to breakage.
No lathe, no problem
Don’t be fooled into thinking you need a lathe to make effective handles for custom tools like these. The last four photos show a simple technique to make an effective traditional non-turned handle.
Photo 18: Begin with a blank 22mm square and at the drill press pre-drill a centred hole of correct diameter and depth. After drilling, use a block plane to create a curved profile on all four sides. When complete, the handle should be 22mm square in the centre and around 16mm square at the drilled end.
Photo 19: Pencil mark an arris on each face which will allow the handle to be shaped to an octagonal section.
Photo 20: Plane each facet to the marked pencil lines.
Photo 21: Smooth off the ends of the handle with a rasp or file prior to applying a finish and fitting the tool shaft.
Troy McDonald is an engineer and woodworker based in Brisbane who writes regularly for Australian Wood Review.