Introduction: Hardwood Hair Combs on the Scroll Saw - Made at Techshop

About: I'm a teacher first and a maker close second. I currently teach woodworking, CNC and laser cutting / engraving at several makerspaces in the San Francisco bay area. Humanmade, The Crucible, and Clayroom. In ad…
In this instructable I'll show you how I made a hardwood hair pick on the scroll saw at Techshop's wood shop.

I had a few reasons for wanting to make this. First, they look cool, and I've always just wanted to have one in my pocket. Second, I've heard that wood combs are supposed to be better for one's hair, compared to the plastic combs I currently use. No static electricity, no edge seams to catch and pull hair, and they naturally redistribute hair oils. 

Finally, I hope one or two of these guys can replace my current army of plastic combs. The picks I currently use come in 3-packs, and no matter how many I have, I always manage to lose them all - at the bottom of a backpack, behind my desk, lurking between shampoo bottles in the shower, etc... I think I have a dozen of the things, and most are lost at any given time. I had the same problem with pens in the past - and since I switched to using a single, nice fountain pen instead of many cheap gels, I stopped losing pens - in fact I haven't lost mine once in years now. I'm hoping I can achieve the same thing with these combs.

Pictured here are my first and second attempts - one is peruvian walnut, the other is purple-heart. I made some design improvements between the two, and I'll just be documenting the process of making the purple-heart comb.

Step 1: Tools & Materials Used

Tools used
  • Scroll saw with #6 reverse skip tooth blade & #5 fine tooth blade
  • Orbital sander
  • Adobe Illustrator software (Inkscape is a good free alternative)
Materials used
  • Thin-stock hardwood, 0.15 - 0.25 inches thick (thicker might work, but these are the two sizes I've used)
  • Sandpaper - 120, 220, 320, 400, 600 grit
  • Printed pattern
  • Spray adhesive + acetone remover
A note about the wood. If you want a THIN comb like the one I'm making here, it's important to choose a straight-grained hardwood, and position the teeth going the SAME direction as the wood grain. Some softwoods may work, but probably need to be thicker to keep their strength. And if the wood grain is the opposite direction, perpendicular to the teeth, the teeth will easily snap apart in the center.

The purple heart I chose is very hard and dense, so even the small tips tapered to ~.05 inches are strong enough to stand up under regular use.

Step 2: Design & Draw the Comb

This is actually my second attempt at a comb. Pictured, you can see one of my cheapo plastic picks next to my first wood comb. I originally just copied the size, tooth-count and tooth spacing of my plastic pick for the design. It looks okay, and feels good, but has a few problems.

The wood is much less flexible than the plastic, so it can't flex to accommodate my hair when I grow it out (right now it's short, I usually wear it really long). Every time I dig deep it gets bunched up and stuck. So this time I spaced the teeth further apart, and also make a wide opening at the base of the teeth, which lets bunched up hair escape - something I copied from the design of another maker who was describing the design of his metal comb (can't find link to that at the moment).

To make the comb pattern I used Adobe Illustrator (Inkscape is an open-source alternative). I've described my process below, but I've also made labeled screen captures to make the process clearer. The final design is included as a PDF and illustrator file at the end of this step.
  1. First I made a line slightly larger than the final width of my comb - I want my comb to be ~2.5 inches, so I made a 3 inch line - you'll see why later.
  2. I used Illustrator's effects menu, and selected distort --> zig-zag. This opens up the zig-zag effects box. I selected preview so I could see the effects of my settings real-time.
  3. The two settings on zig-zag are height (amplitude) and peaks-per-segment (line). My first comb had 11 teeth, which translates to 21 peaks (top and bottom) per line. So for my second comb I reduced the peaks to 15 peaks, which will give me 7 teeth.
  4. After applying the zig-zag I went to the object menu and selected "expand appearance. This changes the zig-zag from a preview shape into an actual vector line.
  5. Next, I made some ovals at the base of each tooth - then I used the pathfinder tool to unite the ovals and tooth shapes, creating the final design of teeth with a bulb-out area between each tooth. The resulting hole makes space for hair to escape.
  6. The reason I made my line larger (3 inches) than my target size (2.5 inches) is because I wanted to cut-off the last peak from the zig-zag. I used the direct selection tool to select the first and last segment of the wave and delete them. I also had to delete some stray lines created by the previous pathfinder process
  7. Next, I used the pen-tool to draw the handle shape. I'm not sure if it was necessary, but I created a second layer at this point, to avoid changing the shape of the teeth while I drew the handle.
  8. I played with the spline settings until I got a half-handle shape that I was happy with, then I used the "transform -->reflect tool to create a mirror copy of my half-handle, then joined the two lines together.
  9. Finally, I made sure the handle and teeth were lined up correctly, then used the "window -->pathfinder --> unite" tool to combine the handle and teeth together. This process created some incorrect artifact lines - I used the direct-selection tool to delete those.
Once I was happy with the pattern, I double checked the dimensions, and printed it out.

Step 3: Cutting the Rough Shape

I used a blank piece of wood that was slightly over-sized, just to make sure I could put my pattern cleanly in the center. I attached the pattern to the blank with 3M77 spray adhesive - I sprayed both the paper and the wood, let the adhesive become tacky, then put them together. Again, remember to position the comb teeth going WITH the grain of the wood, not across it.

Next I cut the outside shape. I did two long cuts around each half of the comb to make the rough shape. There's not a whole lot I can say about scroll-sawing technique - in my experience the tactile feedback and muscle memory are much more important than anything that can be described - if you haven't used a scroll saw much, I'd advise just choosing some easy projects to try cutting lots of different shapes.

I find I get my most accurate, clean cuts when I can tune out everything around me and sort of zen-out meditating on the line I'm cutting - too much thinking leads to hesitation and hand-repositioning, which leaves behind a very rough edge. I tried to cut down the center of my lines - but if you have any trouble try sawing on the outside-edge of the lines - any extra material can always be filed or sanded away later.

Step 4: Cutting the Teeth

When I cut my first comb, I tried to follow the zig-zag pattern in one long, winding cut. Not only was this tiring, it didn't really give my the results I wanted, and I had to do a lot of sanding to even out the teeth, and some teeth ended up smaller than intended.

This time, I made two cuts for each tooth, slicing down the right side and left side, cutting out a V-shape between each tooth. Notice that I left the bulb-out section at the base of the teeth intact - I returned later and cut these out with a different, smaller, blade.

After hogging out the space between teeth, I changed to a #5 fine tooth blade - I used this ti quickly pivot around the bulk-out sections between each tooth. I cut each oval in one pass - the only tricky part was pivoting sharply at the bottom of each one. As I said before, my cleanest cuts were when I cut quickly, with no pauses or hesitation.

I greatly preferred this method - it allowed me to rest my hands briefly between cuts, and led to much cleaner results. And using two different blades also made the process go much faster - the wide, reverse skip-tooth blade cut away large areas quickly, while the smaller fine tooth blade allowed me to easily pivot around the base of the teeth.

If there are any small artifacts remaining, you can try cutting them off with the scroll saw, but it's often easier to file or sand them off.


Step 5: Fine Tune the Edges, Corners and Teeth

To remove the pattern, I rubbed some acetone over the paper with a rag. The acetone dissolves the adhesive, allowing the paper to easily come off.

To fine-tune the edges and inside bits I switched to using a set of needle files and 80 and/or 120 grit sandpaper. I just went over each section and gently sanded / filed until it was the shape I wanted.

Once I cleaned up any obvious artifacts, I switched to just sandpaper and started sanding the edges with 80 grit sandpaper. To round-over the teeth and get rid of sharp edges, I took small scraps of sandpaper and wrapped them around each tooth and rubbed it up and down until I was happy with the roundness. Then I did the same to the sides and handle, until all the edges were rounded. Then I did the same with 120 - 220 - 320 and 400 grit sandpaper to make them smooth.

Finally, before sanding the faces of the comb, I tapered the ends a bit using the standing belt sander. Tapering the ends allows the tips of the teeth to slide easily into even tightly curled hair like mine. They ended up really sharp, don't try to get this thing past airport security :P - I sanded them down a little bit later to make them blunt, but I actually kind of like them a little bit sharp - it feels really good on my scalp.

Step 6: Sand It Smooth & Finish It

After I was happy with all the edges, I switched to sanding the faces. I used a random orbital sander, but it was a bit aggressive - a lighter duty vibrating palm sander might be better suited for small work like this, but this is all I had available. You could also just hand-sand it if necessary.

I sanded it with 120 - 220 - 320 - 400 - 600 grit. That seems like a lot, but I only spent ~10 seconds or less per side per grit, so it only took a few minutes. Since it was so small, I sanded it in two halves - holding one half while sanding the other, then turning it around.

For the finish, there are probably many viable options, but for now I decided to keep it simple and just oiled it. Any natural oil or mineral oil should work - I used the same oil I use on my cutting boards, hemp oil with a bit of beeswax mixed in.