Introduction: A Sliding Bevel for Woodworking (mostly)
Measure twice, cut once goes an old woodworking adage. The idea is that it is easy to make measuring mistakes, but much more difficult to fix them once you have used the (bad) measurement for cutting a piece.
So, measuring once is bad. Μeasuring twice is better. Even better, however, is not measuring at all. Or at least, not using numbers for measuring, opting instead to transfer the measurement directly from one piece to another. This is the idea behind "story sticks", and it works well.
When you are dealing with angles instead of lengths, the equivalent tool is a sliding bevel. The simplest sliding bevel would be two sticks joined at one end with a bolt and nut. Traditionally however, a wooden piece is used for one side of the angle and a metal blade for the other. This makes for a much more convenient and versatile tool. The blade has a slot which allows it to slide, hence the name.
In the past, woodworkers made their tools themselves, or at least some of them. Aside from their practical use, these tools were made in such a way as to showcase the skill of the woodworker. A sliding bevel is perfect for this purpose: It is relatively small, easy to make and the maker can with relative ease add "bells and whistles" to showcase his skills.
In the course of making this instructable, I made 2 complete sliding bevels as well as parts for more. In case you wonder why anyone would want not one but two or even more sliding bevels, there are many reasons. First of all, of course, the practical one: Some videos and pictures shot while making the first one did not come out very well, so I preferred to make a second attempt. Secondly, a nice sliding bevel makes a great gift for a woodworker friend. Alternatively, you can sell them (I have several for sale in my my etsy shop, some similar to the one made in this instructable and some simpler ). Last but not least, it is sometimes useful to have more than one, especially if they have different sizes. If you don't believe me on this point, check this: In the first picture of p. 67, you 'll see that the famous toolbox of Henry O. Studley contained not one, not two, but three sliding bevels. Of course, Henry O. Studley was the ultimate tool junky, so you don't need three sliding bevels just because he was using three...
A sliding bevel can also be used for metal work. Once you get acquainted with it, you 'll find that it will become your tool of choice whenever you need to transfer an angle - be it from another piece, from a design or even from a protractor.
As you will see in the last picture, the sliding bevel consists of 4 parts: A wooden body, a metal blade, a bolt and a nut. I made all four parts, but if you don't have a lathe you can use a shop-bought bolt and nut instead of making them. In this case, I would suggest a brass bolt with a hex head and a brass wing nut.
Note 2020-10-26: If you would like to make a sliding bevel but do not have the equipment needed for this build, please have a look at the new instructable I just posted: A simpler sliding bevel for woodworking.
Woodworking, as well as metalworking, are inherently dangerous activities. Before starting almost every operation, especially those that involve power tools, you must ask yourself two questions:
- What could go wrong here?
- How can I prevent this?
Whenever using a power tool, you need to make sure that the tool and the workpiece are held securely.
Do not use a tool if you are not comfortable with its operation. Do not rush things.
In cases where there are hidden risks, I will indicate this clearly with a "watch out!" section in the respective step.
Step 1: Gathering the Supplies Needed for This Build
The following materials and consumables are needed for making the sliding bevel:
--- Materials ---
- A piece of wood around 25X3X2.5 cm for the tool body. I cut two such pieces from a piece
of bubinga (Guilbourtia spp.) around 25X6X5 cm, from which I made two different sliding bevels. The rest will be used in some other project in the future. You want to use as hard a species as possible. You also want it to be rather straight-grained (to avoid it having internal stresses which may cause it to warp in the future). And you also want to use a species whose looks you like. A high-end woodworking tool needs to have decorative value on top of its usefulness. Bubinga is perfect for this project on all counts.
- A piece of brass around 27X3X0.25 cm for the blade. I had a piece measuring 60X3X0.25 cm. Each blade has a total length of 26.5 cm, so with this piece I could (and did) make two blades (and keep the change). The piece shown in the pictures is a different one, marked for making more bevel blades.
- A piece of 12 mm diameter brass rod for the bolt (optional - you can replace this with a shop-bought hex bolt). Each bolt is around 4 cm long (including the head), so a piece around 12 cm long will be more than enough for the two bevels I made (you need some extra length for holding it in the lathe chuck).
- A piece of 20 mm diameter brass rod for the nut (optional - you can replace this with a shop-bought knurled or wing nut). Around 5cm length will do for two nuts.
- A hex bolt and wing nut (optional). These are only needed if you don't want (or don't have the equipment needed) to make your own nut and screw.
- A piece of teak veneer (optional - you can skip this altogether. Its purpose is purely decorative). For my taste, the more figured it is, the better. I used material from a piece around 85X15 cm (itself an offcut from a previous project). One piece around 28X3 cm is needed for each sliding bevel, but having a bigger piece allowed me to choose the parts with the most interesting grain.
- A piece of inlay banding strip (optional - you can skip this altogether). The one I used is nominally 6 mm wide. I used around 80 cm for the two sliding bevels (4 sides X 20 cm each).
--- Consumables ---
- Cyanoacrylate (CA) glue (optional - if you skip the blade veneer and inlay banding you will not need glue).
- Walnut oil and shellac for finishing. I used walnut oil for the teak veneer and blonde
shellac for the tool body. Using oil on a highly lustrous wood like bubinga is not a good idea. On the other hand, I find that oil enhances the colour of teak. Both materials are extremely easy to apply.
- A pair of disposable gloves and some kitchen paper for finishing.
- Pieces of sandpaper of different grits.
- A piece of softwood, from which several sacrificial pieces will be cut.
Step 2: Gathering Tools: Drafting, Personal Protection
In this build I have used many tools, both for metal and wood working. I also used some "generic" equipment:
--- Drafting ---
- A computer with a CAD application and a printer. You can skip those, but I prefer to make drawings of all but the most trivial parts before starting to work on them.
- Compass: Not strictly necessary, I used it to draw a 45 degree angle for the blade edge. I could have done this in a zillion different ways.
- Ruler: Not much can be done without it.
- Indelible marker: I use it to mark metal (I later use alcohol to remove it) and wood (in places that will later be sanded).
- Pencil: Used to make marks where the marker cannot be used (e.g. in pieces that have already been sanded and/or finished).
- Marking knife: Unmatched for accuracy.
- Vernier caliper: Normally a machinist's tool, I use it all the time in my woodworking too.
--- Personal protection ---
- Protective goggles: These are a must. Wearing them is the first thing I do upon entering my workshop.Please do not attempt to recreate this project without wearing goggles.
- Ear protection: I always use those when using power tools. They are a major annoyance, especially in the summer, but they protect my ears as they will protect yours if you make a habit of using them.
- Shop vacuum: Not strictly necessary, but it helps keep the space and the air clean, which is important for your lungs, among other things. I have one with an auto-start feature which is very convenient: Just connect the power tool to it and the vac starts as soon as the tool draws power. In an ideal world, I would have many of those and wouldn't have to cart it around the workshop. If you don't have a shop vacuum, you should at the very least wear a face mask when working wood.
--- Other ---
- Several spring clamps (optional): You will only need those if you are going to apply veneer and/or inlay banding.
- A pair of scissors: for cutting veneer.
Step 3: Gathering Tools: Woodworking
For the woodworking part of this build, I used the following tools:
- A desktop bandsaw (mine is a Metabo BAS 260). Theoretically you can do without the bandsaw if you are very skilled in sawing straight. In practice, I wouldn't even contemplate this project without the bandsaw.
- My "poor man's wood milling machine". (optional but highly desirable). You can skip this if you forego the inlay banding and use the bandsaw for making the slot for the blade. It consists of a cross vice, a router with a 43mm neck and a drill stand. I have published a separate instructable on it.
- A belt sander attached to your workbench, with different grits of paper (P24 to P320)(optional). If you don't have one, you can use a palm sander instead. The belt sander however is much more aggressive, meaning you'll spend less time sanding.
- One or more 1/3 sheet palm sanders with different grits of wet-and-dry sandpaper (p280 to p1000). You can do your work with one, but if you have more you won't have to constantly juggle papers. Plus they are dirt cheep. I have 4 of those and used them all in this build. I could use a couple more.
- A power drill and 6mm drill bit for wood. My drill is an old Bosch model. Any one will do.
Step 4: Gathering Tools: Metal Working
I used the following tools for metal working. Some of them can be skipped (especially if you op to use a shop bought bolt and nut (but where is the fun in that?).
- A mini metal lathe with cutting tools and other accessories (optional). Mine is a 30-year old Russian model, which I bought second-hand around a year ago. It has a bad bearing which needs replacement, and results in a bad surface of the workpiece, but I work around this issue until I find time to fix it.
The accessories I used include
- a tailstock chuck
- a live center
- a quick-change tool post
- a knurling tool
- a center drill bit
- drill bits in different sizes
- a 5mm reamer
- several lathe cutting tools, including a shop-made one for the concave part of the nut,
- a 6mm carbide end mill. You can skip all those if you use a shop-bought bolt and nut.
Aside from those, I also used some of the woodworking tools from the previous step.
Step 5: CAD Drawings
Whenever I make something that is not totally trivial, I like to begin by making some drawings in a CAD program. This helps me better visualise the end result, try different variations etc. In some cases I try to then follow the design as closely as possible. In other cases I only use it as a rough draft and improvise along the way.
The sliding bevel in this instructable consists of 4 parts: The wooden tool body, the blade, the bolt and the nut. I saw no reason to make a drawing of the bolt (I had a perfectly clear picture of it in my mind), but I did draw the remaining 3 parts.
For the nut I also made a second drawing with a grid to facilitate measurements at make time. I also made a drawing of a simpler version, without the curved part. This one also came in two versions, with and without grid. I have designed the grid in such a way that I can measure dimensions at a glance, without having to count lines.
I am attaching the CAD drawing files here, in case you want to view and/or modify them.
Step 6: Making the Bevel Body - I (cutting, Shaping, Preliminary Sanding)
With the design complete, the next step is to make the bevel body.
In this step I used the bandsaw, the belt sander and two palm sanders.
I first cut a piece with the bandsaw. I left a little extra material, around 1 mm on each side, to account for the material that will be shaved away by sanding. In this step the exact size is not critical, except from the width, which must eventually match that of the blade.
After that, I started shaping the round edges of the body bevel. I did this on the belt sander, but I could have started with rough cuts on the bandsaw. I do feel pretty comfortable shaping wood on the belt sander, which is why I chose this approach. The first sanding belt I use is very coarse (P24) and makes quick work of the shaping, even with a wood as hard as bubinga.
The number one secret when shaping a curve with the sander (especially with a belt sander, which is much more aggressive) is to keep the sander (or, when the sander is fixed as in this case, the workpiece) constantly moving. If you leave it stationary, be it for just a moment, you will produce a flat surface instead of the curve you want.
The second secret is not to expect the shape to be completed when rough sanding. With the coarse grit, you should simply aim to approach the final shape. Instead of a curve, at this step you will only get a series of flat surfaces. As you progress through finer and finer grits, however, the workpiece will almost magically take the shape you want.
As you progress from coarser to finer grits, you should apply less and less pressure, in order to remove less and less material and leave a better surface.
One last trick: When you sand flat surfaces, use two steps for each one of them: sand it in one direction, then turn it around 180 degrees horizontally and sand it again (in the opposite direction this time). The reason for this is that it is very difficult to keep a uniform pressure on the workpiece. You may be pressing more toward the back side, or toward the right one. When you turn the piece around, you will compensate for this and remove an equal amount of material from both sides. Keep doing this with every successive grit and you will get good results. It goes without saying that here, as everywhere, practice makes (almost) perfect.
Having roughly shaped the body, I proceeded to sand it with progressively finer grits - up to P180 with the belt sander. I did not soften the edges at this step, as I will need them sharp to make accurate measurements off them in the next step. Having reached P150, I started wetting the workpiece between grits with a wet piece of kitchen paper. The purpose of this is to raise the grain and cut it with the next grit. Otherwise the grain is just pushed down and is suddenly raised when you apply finish.
- Whenever you use a bandsaw, you need to be careful to avoid approaching the saw blade with your fingers - especially the cutting side. Use a push stick whenever you approach the end of the cut.
- When you use a stationary belt sander (and many other machines), you need to be extra careful that the belt doesn't catch your sleeves. I 've spent thousands of hours on this specific belt sander, so doing this is second nature to me - but even this doesn't mean I am safe. I had a friend, a professional machinist with several decades' experience at the time, who lost a finger in a work accident.
Step 7: Making the Blade - I (Marking)
The next step is to make the blade. This consists of the following operations:
- Cutting the slot
- Cutting the blade edges
For marking, I based myself on the printout of my CAD design for the blade. For the first bevel, I opted to mark the 45 degree angle using only a compass and ruler, basically because I was in the mood of doing so. I could just as well used a protractor or any other method. I used a spare piece of plywood as "paper" (it will eventually be veneered, so the marks won't hurt). The drawing above shows the concept. I transferred the angle onto the blade blank with a ruler and indelible marker. I then marked the semicircular end freehand. For the second blade, I transferred the angle from the CAD drawing using a ruler. For the third one I transferred it, again from the CAD drawing, but this time I used a previously made sliding bevel (after all, it is my go-to tool for transferring angles).
I then proceeded to mark the slot. Using the printout, I marked the approximate ends of the slot. Then I used the ruler to mark the center points of the blade at the positions of the ends, marked the points at 3mm on either side of each center point and joined these points with straight lines. This (along with the cutting operation that follows) is one of the few operations in this build where we want accuracy, as we want the slot to be centered in the blade.
Step 8: Making the Blade - II (Cutting, Shaping)
Having marked the slot, I then proceeded to cut it. For this, I used the mini-lathe with the milling attachment. I attached the milling attachment to the lathe cross slide, placed a 6mm end mill in the lathe chuck, grabbed the blade blank in the vice of the milling attachment, adjusted the vertical position of the vice so that the end mill was exactly at the height where the slot needed to be cut, started the lathe, moved the cross-slide all the way to the front, then moved the carriage toward the headstock until the end mill had passed through the blade. After that, I enlarged the hole into a slot by moving the cross slide toward the back. Then I stopped the lathe, moved the cross slide back to its original position, opened the vice, moved the blade to the back, tightened the vice again, started the motor and enlarged the slot a little more. I repeated this until I had cut the entire length of the slot, as marked.
To cut the blade edges, I used the metal cut-off grinder. First I cut the 45-degree end, then I rough-cut the circular end, making 3 cuts just outside the mark line. Copper (the main ingredient of brass) is a good conductor of heat and the cutting operations produce plenty of heat, so I had a can of water nearby and immersed the brass pieces in it after each cut to cool them down. Next I moved to the bench grinder, where I proceeded to grind the ends of the blade to the exact shape I wanted and to soften the edges.
Having completed the cutting of the blade, I moved to the bench grinder to remove the angles from the curved end. Here, as when shaping the body in the belt sander, the same method applies: shape the blade by hand, guided by the marked semi-circle. As you approach the desired shape, apply less and less pressure in order to remove less and less material. Keep the workpiece moving.
When I had completed shaping in the bench grinder, I wiped the blade with alcohol in order to remove the marks, then used the palm sanders in order to get a nice, satiny surface and to remove any sharp edges. I used 5 grits of wet-and-dry paper: P180, P240, P320, P500 and P800.
When cutting the slot, at any given moment, the vice must hold the blade tightly. If at any point the entire part of the blade that is held by the vice is slotted, it is no longer held safely: it can (and probably will) be grabbed by the end mill bit, especially if it has a spiral shape like the one I am using, and be drawn toward the headstock. Once it leaves the vice, it may start rotating and may harm you or be thrown at you. Most probably the blade will be destroyed, and it may well harm you too! I hope the diagram explains this clearly.
Step 9: Making the Knurled Nut
To make the nut, I started with the CAD drawing which I had printed out and placed near the lathe, but I only used it for reference, without following the exact measurements. I found that I prefer the nut to be slightly smaller than the drawing, especially when I make it for a sliding bevel that is smaller overall.
First, I attached the 20mm brass rod in the lathe, placed a mark on it with the marker so I could reposition it with the same orientation in the chuck in case I had to remove and replace it (this is standard practice, but in this case it was unnecessary as I didn't need to remove it from the chuck). I began by turning down to 18mm the part of the blank that would be used for the nut.
With the lathe turning, I used the marker to cover the last part of the blank with ink. Then I made a line into the inked part with the dial caliper, 13mm away from the end of the blank (the size of the nut minus the knurled part). After that, I turned down the last 13mm to a diameter of 13mm. With the lathe turning, I used a metal file to soften the edge I had just turned, taking care to:
- Keep the file from getting grabbed by the chuck and thrown at me
- Keep my body away from its hypothetical trajectory, should the above happen
After that, I turned the concave part of the nut using a shop-made cutting tool I had ground for this purpose. Then I used the knurling tool to make the knurled part of the nut.
This completed the exterior shaping of the nut. I now had to make it into an actual nut, by making the hole and the internal thread. I did this work on the lathe for the accuracy it gives.
I wanted a hole with a diameter of 5mm (for standard metric threads, you obtain the hole diameter by subtracting the thread pitch from its size - in this case, I wanted a M6X1 thread, so the hole was 6-1=5). I started the hole with a center drill bit attached in the tailstock chuck. Functionally, this bit does more or less the same work as a normal drill bit, with one big difference: Its rigid, thick body prevents it from flexing and ensures that the hole will be started at the exact center of the workpiece. I then marked the depth I wanted (The size of the nut + an extra 10mm for the "nose" of the thread tap) onto a 4mm drill bit (slightly less than the final hole diameter - the drill bit doesn't give a good finish), attached the drill bit into the tailstock chuck and proceeded to drill the hole. Since I had started the hole with the center drill bit, the 4mm drill bit continued from there and remained on-center. I then finished the hole with a 5mm reamer, which produces a hole with a great finish. After that, I replaced the reamer with the first of a set of M6X1 taps (the 3 taps in the set are marked with lines - contrary to what one might think, the progression is NOT 0->1->2 but 1->2->0 lines) in the tailstock chuck and started manually turning the headstock chuck while pushing the tap into it. A bit of light oil helped get the cutting of the thread done with less resistance. After I had the first tap bottomed out, I removed it by turning the headstock in the opposite direction and enlarged the thread with the second and third taps in the set. I then completed the thread cutting with the long-shank tap, which could reach further into the hole.
The next step was to cut off the nut from the rod. I first inserted a 3mm drill bit nose-first into the tailstock chuck and moved the tailstock so the queue of the bit was inside the nut. I then proceeded to cut off the nut with the parting tool. The purpose of the drill bit (a plain rod would have done) was to hold the nut when it was separated from the rod and keep it from being huled at me (or elsewhere).
Then I removed the rod from the headstock chuck, attached the nut to it leaving the knurled part outside and proceeded to face the freshly cut surface. I completed the work with some more file work, very carefully this time as I was working very close to the chuck jaws.
Just before removing the nut from the lathe, I made one last pass with the long-shang tap, to make sure the thread was OK.
The nut was now complete, needing only some final sanding - the reason for this is that my lathe has a bad bearing and produces a less than perfect surface (I'll work on this when I finish this instructable).
Step 10: Making the Bolt
Making the bolt involved 5 steps:
- turnin down rod from 12 to 6m
- cutting thread for the part of the bolt that will protrude from the body.
- cutting off bolt from rod
- milling square head
- softening edges with grinder and sander
I gripped the 12mm brass rod in the lathe chuck. As with the nut, I started by marking the length of the part I wanted to turn down, using a marker and the vernier caliper. The length in this case was 20mm (the thickness of the body) + 18mm (the length of the nut) -5mm (the thickness of the bolt head) - 1mm(I wanted the bolt end to be a little shy of the nut) = 32mm.
After marking, I turned the bolt body down from 12 to 6mm. I used shallow passes of 0.25mm, each of them removing half a millimeter of thickness (0.25 from each side), but instead of relying on a calculation I repeatedly stopped the lathe and measured as I was getting to my target. When I reached around 6mm, I stopped the lathe and proceeded to cut the thread.
In order to cut the thread, I left the blank in the lathe, pressed the die wrench with the M6X1 die against the tailstock quill and moved the tailstock until the die touched the end of the blank. I then locked the tailstock in place and started turning the lathe chuck with my hand while pushing the tailstock quill against the die wrench. This procedure ensured that the die would be kept at a 90 deg. angle to the blank and a good, uniform thread would be cut. I stopped the thread around midway, as I didn't want the part of the bolt that would be inside the body to be threaded.
When the thread was complete, I turned (by hand, again) the lathe chuck in the opposite direction in order to remove the die and used a parting tool to cut off the bolt from the rod. Similar to what I had done with the nut, I used a piece of rod with a hole (around 8mm) in the tailstock chuck, to catch the bolt once it got separated from the rod.
Once the bolt was cut off from the rod, I marked a square at the top of the head. I then removed the quick-change tool post from the lathe cross-slide, replaced the milling attachment, grabbed the body of the bolt in the vice of the milling attachment and proceeded to make 4 cuts with an end milling tool attached in the lathe chuck. I now had a bolt with a square head. I prefer this to a standard hex head, both because it is easier to make a square hole in the bevel body and because it is an unusual shape for a bolt head. While I was there, I proceeded to flatten the top of the bolt head, which still had a small protrusion at the center, where it had been attached to the rod.
After that, I went to the bench grinder to give a slight curvature to the bolt head and soften the angles. Then I sanded the head using the palm sanders, until I got a nice matte finish.
Step 11: Making the Bevel Body - II (milling Work)
Having essentially completed the metal parts (functionally, if not cosmetically), it was time to return to the wooden body of the tool.
At this step, I needed to do the following:
- Make the hole for the bolt
- Mark the hole for the bolt head
- Enlarge the hole for the bolt head
- Cut the slot for the blade
All these operations were performed in my "poor man's milling machine. Each one of them could have been performed without the milling machine, but this would have been much more difficult.
To make the hole for the bolt, I placed the body in the "poor man's milling machine". To protect the surface of the body from being marred by the vice jaws, I wrapped it in a piece of paper folded 3-4 times. I then moved the cross vice until the cutting tool (a 6mm spiral bit) was exactly above the hole position. I then started the router and slowly lowered it to the body, taking shallow cuts and raising it in between to make sure sawdust was removed. I could have used a drill press, but the router bit makes a much cleaner cut.
I then screwed on the bolt and nut, turned it until the bolt head was exactly in the angle I wanted, tightened the nut and used the marking knife to transfer the sides of the bolt head onto the bevel body. In some bevels I place the head parallel to the body sides (this is easier to mill). In others, I place it at a 45-degree angle, which I find more interesting.
After that I removed the bolt and nut, replaced the bevel body in the milling machine (I used a jig to hold the body where I wanted the hole at a 45-degree angle. For the bodies where I want the hole parallel to the sides, I hold it directly in the cross vice using a sheet of paper folded a few times to prevent the vice from marring the workpiece), replaced the 6mm bit with a 2mm one, placed it into the existing hole (at a depth of 5mm, corresponding to the bolt head size), started the router and started moving the cross vice until I had enlarged the hole according to the marks. I then replaced the 2mm bit with a 1mm one and cut the angles. After that, I removed the body from the milling machine and tried the fit of the nut. Where necessary, I fine tuned the cut. In this case, it pays to go slowly and sneak up to the final cut - if you remove too much material the result will not look good. What you want is a tight fit, but not too tight. It must be easy to insert the bolt all the way through and to remove it, but it must not fall out on its own.
To cut the blade for the slot, I gripped the bevel body in the appropriate direction in the cross vice and started cutting with a 3mm milling tool. This one is an extra long tool, which makes it more prone to breaking. For this reason, I took several light passes of 3mm depth each. It is generally safe to cut a slot as deep as the width of the cutting tool. When I reached a little more than half the depth of the workpiece, I stopped the motor, released the workpiece, turned it around and started cutting from the other side. Again I used passes of no more than 3mm, but now I had a problem similar to the one encountered earlier, when I milled the slot in the blade (see the last paragraph of step 8): If I had continued all the way, when I removed the last shreds of material the jaws of the vice would have pushed the 2 "jaws" of the body inward, those would have grabbed the cutting bit but at the same time they would have been released from the vice. In short, the workpiece (and possibly I too) would be damaged. Of course, a similar problem has a similar solution: Instead of removing all the material at once, I removed a little at a time, moving the workpiece relative to the vice in between. See step 8 and the pictures here for a clarification.
In order to complete the blade slot, I had to cut its end at 45 degrees. In order to do this, I released the body from the vice, then gripped it again (from the part that had not been cut yet) at that angle. I cut the angled end up to half-depth, then reversed the body to cut the remaining half. Now I had to grip the body from the part that was already slotted, which presented the same problem again. This time to solve it I assembled the entire tool (i.e. body, blade, bolt and nut) with the blade at 45 degrees. This way, the blade was holding the "jaws" of the body apart and I could grip it securely.
Now the slot was completed, but its surfaces, after all this step-wise milling, were uneven. I used a thin hand file to flatten them, then sanded the slot edges with a piece of P240 sandpaper to soften them.
Step 12: Making the Bevel Body - III (inlay Banding and Final Sanding)
Having completed the slot for the blade, it was time to apply the inlay banding and proceed to the final sanding and finishing of the body.
To cut the slots, I first marked their ends.
I continued by cutting the slots for the inlay banding. To do this, I turned the body in the cross vice by 90 degrees. To make sure it is absolutely horizontal, I first used a flat piece of wood to register the top of the bevel body with the top of the vice jaws. To check that it was indeed horizontal, with the router motor stopped I moved the cross vice all the way toward me, lowered the router until the tip of the tool touched the top of the bevel body and noted the indication of the depth scale. Then I moved the cross vice all the way to the back and repeated, checking that I got the same indication. This step is important, as otherwise I would get a slot of unequal depth which would be useless.
I then started the router motor and, checking the depth scale, lowered the router bit a little less than 1mm (the thickness of the inlay strip) into the body. I locked it into position and moved the cross vice until I cut the entire length of the slot as marked previously. As the length of the slot is longer than the travel of the cross-vice, I had to stop midway, move the body inside the cross vice, readjust the body then complete the cut. Then I turned the body so the bottom side came to the top and milled the second slot.
With the slots complete, I placed the inlay strip next to the first slot and marked the position where I needed to cut it. I like to position the inlay banding so that its decorative features are centered. Although this is not strictly necessary, I find it looks much better this way. I cut the inlay strip a little oversize with a pair of scissors (around 1-2 mm extra on each side), then trimmed it until I got a perfect fit. Then I used a palm sander with P180 or P240 sandpaper to round the edges so they matched the ends of the slot. I only had to sand the sides of the strip to make it fit in the slot. Although the strip is nominally 6mm wide, in actual fact it is closed to 6.2mm.
When I got the inlay strip to fit in the slot, I could glue it in. I first cut a few pieces of kitchen paper and placed them on the workbench near me. I used CA glue for the inlay strips, because it dries fast and strong. CA glue, however, is the glue of choice when you want to glue your fingers together - again, it dries fast and strong. When you don't want your fingers stuck (and in this case I didn't), you need to wipe away immediately any CA glue you touch. I could have used gloves, but in this case I didn't bother. Next, I gathered the spring clamps I would need and placed them near the kitchen paper. I got a straight piece of wood against which I would clamp the body and inlay strip and wrapped it in a sheet of paper (there was bound to be a little overflow of CA glue and if this piece became stuck to the body it would be a minor disaster). Once you start applying CA glue, every moment counts, so you want to have everything ready and within easy reach.
I then applied CA glue inside the slot. In one case I overdid it and had to wipe off the excess with one of the pieces of kitchen paper. Then I inserted the piece of inlay strip into position, pressed the paper-wrapped piece of wood against the inlay strip and clamped everything together.
After around 5 minutes I removed the clamps and separated the bevel body from the backing piece of wood. Paper had stuck to the body in a few places, but his was expected - it would be sanded away afterward, along with the few stains from CA glue overflow. The inlay strip stood a little proud of the surface of the bevel body but again this would be sanded away afterward. I repeated the gluing procedure with the second strip in the flip side of the body.
Having glued the inlay strips to the body, I proceeded to sand it with progressively finer grits using the palm sander. I started with P240 grit, insisted until all the paper and glue stains were sanded away and the surface was smooth to the touch, then gave it a final touch with P320 and P500 sandpaper. I avoided using the belt sander at this step, as it is too aggressive and could easily cut through the inlay strip. With each grit I sanded all surfaces and smoothed all edges. As before, I used a wet piece of kitchen paper to raise the grain between each sanding step - this gives a much better surface and makes the finishing easier (otherwise I would have had to sand again between each successive coat of shellac).
The body was now complete. All I had to do was apply finish. Bubinga being a lustrous wood, I opted for the use of shellac. To apply it, I used a piece of kitchen paper. The secret here is to "caress" each surface with the wet paper, avoid stopping and just "fly off" at the end. Any defects (dust specks, uneven wetting of the surface) are ignored while the shellac is wet and fixed with sandpaper when it dries (shellac only takes a few minutes to dry), then the next coat is applied. It is very easy when you get the hang of it.
Step 13: Finishing Steps
At that stage, the sliding bevel was completely functional. There remained a few odds and ends which I wanted to fix for cosmetic reasons.
First of all, the finish on the nut was less than perfect. This is mostly due to a bad bearing in my lathe, which causes the motor pulley to vibrate and the vibration is transferred to the lathe chuck and the workpiece. This defect doesn't affect the operation of the sliding bevel, but it does affect its looks. Having devoted so much time to making this tool, I found it worthwhile to spend some more time to fix this imperfection.
I wanted to sand the nut, but in order to do so, I needed to hold it somehow. I thus turned a bolt with the same thread as the nut (M6X1) and left the head round (I won't describe how I did this: the procedure is the same as the bolt for the bevel, minus the squaring of the head). I then gripped this bolt on my power drill and screwed the nut to it. (Using the lathe for sanding would not have been a good idea: in general, it is not advised to use sandpaper on a lathe, as this removes particles of abrasive which can then nest in the lathe ways and abrade them.) Turning the nut with the power drill, I touched the surfaces I wanted to sand with sandpaper (first P240, then P500) until I got the result I wanted. I also touched up the edges to smooth any remaining sharp spots.
There was one last thing I wanted to do before calling it a day. You may have wondered why, although the blade is 2.5mm thick, I milled a 3mm-thick slot for it. Or, you might ask why I included the piece of veneer in the materials, which I have not yet used. Well, the reason is that I was planning to veneer the blade.
Veneer is usually applied to a wooden substrate, but there is nothing preventing us from veneering a metal blade. Now I like brass, especially when it has a satiny texture, but I like wood even more. I would have made a purely wooden blade, but tools must be able to withstand a beating, and a wooden blade wood sooner or later break. I thus came up with this solution, which gave me the best of both worlds: the strength of metal and the looks of wood.
To veneer the blade, I started by cutting a veneer piece slightly larger than the blade choosing the most interesting part of the veneer leaf I had at hand. I applied CA glue to the blade and used a wooden offcut to spread it all over the surface of the blade, making sure to leave no point without glue. Then I placed the veneer on top of a paper-covered piece of wood and placed the blade (glue-face down) on top of the veneer. I applied as many spring clamps as possible and waited for around 5 minutes for the glue to dry. I then removed the clamps, cut off as much extraneous veneer as possible using the scissors and a cutter, then used the sander to sand away the rest. For the slot, I placed the blade in the milling machine and using a 5mm bit I milled away most of the veneer covering the slot. I had placed the blade with the veneer facing downwards and was extra careful not to let the bit touch the blade itself. I then used a piece of P240 grit sandpaper folded in two to remove the parts of the veneer that still protruded into the slot.
I carefully sanded the face of the veneer with a palm sander and P240 paper and applied walnut oil (my finish of choice for teak) to the veneer. Oil finishes are notoriously easy to apply - you just brush them on the wood with a rag. For small parts I prefer to use a piece of kitchen paper. The only downside to using walnut oil is that it takes a long time to dry.
After a day the finish was dry and I assembled the tool. It was now ready to be used.
Runner Up in the
Build a Tool Contest