Intro: Dragon Backpack With Laser Cut Scales
I teach a maker class at a middle school and was thinking this summer of new projects that they could do. I have been inspired by all the cosplay makers I see on the internet. Specifically the scale mail projects I have seen. I decided I "wood" give it a try using wood and our school's laser cutter.
- pine plywood
- 1/8" hardwood ply for laser cutting
- Sinew thread (does not wear rubbing on wood as fast)
- Wipe on polyurathane
- Coping saw
- Belt sander
- Sand paper
- Box cutter
- Laser cutter (we use Glowforge)
Step 1: Making the "Strap" From Plywood
I started off with some rough measurements of my chest and back to get a shape of the inside of the strap. With these I rough sketched on a piece of 3/4" pine plywood and cut it out intentionally small and with plenty of extra so that I could trim until it fit me comfortably. I used a bandsaw to do this. Once I was satisfied with how it fit me I could sketch out the outer perimeter that would not be touching my torso. I put the triangular point on the back to give it a wing look and to act as a handle. I cut this area out using a coping saw since a bandsaw can not cut a hole without cutting through one edge.
The bandsaw does not give a perfectly smooth edge so before using a router with a round over bit I used a belt sander to blend the curves that I had cut. After routing I sanded everything smooth.
It this point I decided that I would carve a little dragon face on it. I like to use a box cutter for this type of carving. Changing out blades when they dull is easy. I also put hole for the bag to be attached to later using a drill.
Finally I applied three coats of wipe on polyurethane. This does not get the plywood shiny but it seals it. If you want it to be shiny you will need many many coats and to sand between layers.
Step 2: Designing and Laser Cutting the Scales
I decided to use TinkerCAD to design the scales. It is very easy to design simple parts for laser cutting here. Also my students are very familiar with it. I googled scale mail to get and idea of what the shape of the scales that other use. I ended up designing two versions of the scales. Both are linked here
Then I exported the SVG from TinkerCAD and uploaded directly to our Glowforge to start cutting from 1/8" ply. I like the cheap stuff from home depot for my class, only $12 or so for 4'x8" sheet. I ran the Glowforge at full power and 190 speed. The material has a bow to it sometimes and does not cut all the way through at times. I don't mind and just punch them out and call it good. You will need a lot of these.
In the future I Think it would be fun to play with the shape of the scales even more and get even more interesting patterns.
Step 3: Sewing Up the Bag
I do not have sewing machine. I know that I could have made the bag a lot better if I did. I have done some sewing in the past and now some of the issue that I have run into when sewing a bag. I decided I would try to eliminate them by using an old pant leg and sewing a taper at the bottom to look like a dragon tail and a really bad hem on the top that I will later fix to put in a drawstring. For now I just wanted to show my students and get them thinking.
I held the pant leg up to the plywood "strap" and sketched in pencil the shape I was going for. I made sure I gave myself about and extra half inch for seam allowance. Then I cut it and turned it inside out to sew it up by hand. I did a very large stitch hem on the top since I knew I would be fixing this later.
Then I had my bag shape and was ready to "scale it up!"
Step 4: Sewing on the Scales
This takes a lot of time. So join a knitting or crocheting group wile you do it :)
I was going for an of set pattern like scales typically are and like you can see in the photo where they are all laid out. The sewing of the scales was started from the bottom. This makes it easier since the other scales are not in the way as you build.
I laid out one row at a time trying to keep the pattern that I wanted. I would trace the hole with a pencil at each location. Keeping the pattern proved difficult since the diameter of the bag changes at it goes up. I just tried my best and any error I tried to hide near the seam that would be attached to the strap since it would be more hidden.
I have two stitches on each scale so that it does not move too much and stays in the orientation that I want. One stitch would not be enough I do not think. I used waxed sinew thread. The video shows the method to my madness.
Step 5: Attaching the Bag to the "Strap"
Once all the scale are on I attached the bag to the "strap" using waxed sinew. I have found that this does not wear on wood as bad and is strong. By hand stitching through the seam that was in the pant leg I though I would get more strength and hide the seam at the same time. I attached the top and bottom end first so that everything was a little taught. I thought this would make it easier to sew up the rest of the bag. I stitched through each hole in the "strap" twice as I attached it.
Step 6: Get Yo' Dragon On!
This means wear it and have fun!
Second Prize in the