Final Project

5/2/18

My final project is going to be a Captain America shield. I'll make it out of wood and engrave it, then I'll attach straps on the back, and have LEDs on the front that are wired in the back.

To start, I need to find wood that's light enough that the straps don't break off when that's the only thing supporting the shield. The wood also needs to be thick enough that the strap mounts can be screwed on without the screw penetrating all the way through.

5/3/18

The shield diameter is going to be 20-22 inches depending on how much wood is available. To attach the strap mounts, I'm going to try engraving a rectangular shape into scrap wood, then making a border that should fit in to the rectangle. I'm going to experiment with this to see if it works.

5/4/18

Today I made the outline of the shield in VCarve. It's going to have a diameter of 22 inches. One I cut the demo piece, I'll be able to see if that attachment method works. Until then, I can't cut the main shape.

5/7/18

Today I cut and measured the Demo piece. I drilled down the main board, and then followed the same steps as the Shopbot project. This was the result:

I measured the areas I'll need with the Caliper. The outer rectangle is 3.23 by 2.46 inches. The inner rectangle was 2.76 by 2.03 inches. The space engraved was 0.215 inches wide. With these measurements, I should be able to create a piece that locks into the lines on the piece.

5/8/18

Today am I designing a piece to fit into the engrave lines. First I make the outer rectangle, which is 3.23 inches by 2.46 inches. Next, I extrude the rectangle by 1 inch. I need a half inch that will fit into the line, and then an extra half inch on top.

Next I add the inner rectangle, which is 2.76 by 2.03 inches. I then make it so it is centered, with 0.215 inches of room to fit into the piece.

Finally, I make an extruded cut that is 0.5 inches deep, which is how deep the engraving is, and I fillet the edges to match the curve the Shopbot made. The fillet radius is 0.2 inches.

5/9/18

My part printed, but unfortunately, One edge was too wide to fit into the wood. After about a half hour of filing, it did fit in, but it was very, very tight. What I am going to do now is cut off one edge of the 3D printed piece. This will also allow me to slide a leather strap under the piece to secure it, and it will be easier to fit into the engraving.

First, I extend the extruded cut to 3.15 inches, so it cuts off the side.

Next, I remove the fillet on the two edges next to the cut I just made. After that, I shorten the length of the piece to 3.15 inches. This way, I know it will fit in.

Finally, I shorten the length of the piece that fits into the wood down to 0.2 inches, not 0.22. This will allow me to ensure it will fit, even if it is looser than the first test.

I print the piece so I can test it again tomorrow.

5/10/18

I printed the new piece, and it fit extremely well! However, the pegs are a bit too long, and the strap wouldn't be held down properly. I shorten the pegs to 0.35 inches instead, and change the total width of the piece to 0.9.

Now I need to figure out where to place the mount lines on the piece. I'm going to plan this out on paper.

Those are the relative locations of where the strap mounts will be. The coordinate points are used to place the rectangles in VCarve. I measured it out so the straps will rest on the right locations on my arms.

5/11/18

Using the coordinates I planned out yesterday, I create the rectangles in VCarve.

I make sure the cut depth is 0.5 inches, and the vector cuts ON the line, not on the outside or inside.

This is the final design for the shield. This will be the back of the shield, where the straps are.

5/14/18

Today I made the engraving file for the shield. I made the file 40 in by 28 in, which is the size of the big laser cutter. I start by making a circle with 22 in diameter, which is the size of the shield. The following rings decrease in diameter by 4 inches. There's a 22" ring, an 18" ring, a 14" and a 10".

Finally is the star. There are two radii inputs for making the star. The first value is the distance from the top point to the center, the second is the distance from the inner points to the center. Because the last circle is 10 inches, I make Radius 1: 5 inches, and Radius 2: 2 inches. This makes the outer points touch the circle edge, and the star is the same shape as the real shield. I delete the outermost circle because the shield will be cut there.

5/15/18

Today I added the 5 lines on the star that can be seen in the left picture. This is a screen shot from one of the movies which clearly shows there are lines crossing the star.

5/16/18

I cut the shield today! It worked out great, the test mount fit perfectly, and there were no Shopbot issues. Tomorrow, I'll hopefully engrave this and print the mounts.

5/17/18

I sanded down my piece today to make the edges less rough. The Laser cutters were all taken up by other classes, so I couldn't do the engraving today. I printed two of the mounts. I also changed the Adobe Illustrator file, because the shield's new diameter was less than 22 inches because of the way I cut it. I added the outer circle back, with a diameter of 21.75 inches instead of 22. I should be able to engrave it tomorrow.

On the 3D printer, to make the mounts sturdier, I changed the Infill to 100% and the number of shells to 10.

5/21/18

Today I engraved the shield. I bring it to the large laser cutter, and save my engraving file to a flash drive. Once the wood is set and ready, I can print the file.

I set the DPI down to 300 to SIGNIFICANTLY cut down time, and edited the file a bit. I removed the outer circle, and changed the star stroke to 2 instead of 5. This way, the points of the star don't stretch past the circle, which they had been before. I make sure Auto Focus and Vector Grid are clicked. I set the speed to 100% and the power to 15% in case the design is incorrect and I need to sand it away.

To make the star show up, I have to increase the stroke. To solve the issue of the points extending too far, I made a circle slightly bigger than the one around the star, and made it white so it covers up the points. This was a good solution to my issue.

I run the file a second time, increasing the power from 15% to 75%. This should make the cuts a LOT deeper, and really make the design visible.

The design is still pretty hard to see, but you can tell that it's there. This is all I'm going to do for the engraving.

5/23/18

Over the weekend, I bought screws and a belt for the straps. I can cut the belt to make the straps, and it's a simple alternative to raw leather. I also have my 2 strap mounts ready. I drill two holes into the each strap mount.

I cut the end of the belt off, and lay it in place over the slot. I slide the mount into place on top of the belt, and it fits in tight enough, and is very secure already. I drill the screws in, and they puncture through the belt and into the wood. I make sure there is enough slack for my hand to fit through, and I drill in the other mount. This side took a bit of sanding, but I made it fit.

5/24/18

I edit the strap mount and change the thickness of the pegs from 0.2 inches to 0.17. This way the next two mounts should fit in much easier. I print the next two with the same settings as before, 100% infill and 10 shells.

I made a change of plans for the LED part of the project. Instead of drilling holes and lighting up the front of the shield, I'm going to run a string of LEDs around the circumference of the circle. I'm going to attatch a switch to the lights so they can be turned on and off. To do this, I need to make a box to hold the switch. I measure the switch from end to end to see how big I need to make the hole in the box.

The box is going to be a cube, where each side is 1.25 inches long.

5/25/18

Here is the box before cutting. The lines on some of the sides are so I can have a flat base to glue to the shield. Rather than design the pieces so they are flat, I just added a line to cut off the tabs. The bigger hole is for the switch(0.785in diameter), the smaller hole is for the wires to come out of(0.4in diameter)

5/29/18

Today I attached the second strap to the shield, using the same process as before, but leaving more slack for my whole arm to fit in.

I also cut and pieced together the box for the switch. I printed it out on wood, and because it took two times to print, it didn't fit perfectly, and I used tape to hold it together. I used Vector only, and made the Speed 35%, the power 100%, and the frequency was 500 Hz.

5/30/18

Today I soldered the switch and lights. The switch was pretty simple. I took the positive wire from the battery and connected it to one end of the switch(red wire). Then I added a white wire to the other side of the switch, which will act as a negative wire. I attach the LEDs to the circumference of the shield.

There's a gap because there wasn't enough on either spool to wrap around the whole shield. So in order to connect the two strips, I need bridge wires connecting positive to positive and negative to negative. I solder these, and to hold the connection, I put hot glue on top of the connections.

Finally, I connect the switch and the battery to the LEDs. The black wire connects the the negative copper spot, and the white goes to the positive. I drill down the battery holder next to one of the strap mounts, and insert the battery. Now all that's left is to glue down the switch and glue down all the LEDs and wires to keep them in place.

5/31/18

Today I glued down everything. I started with the box and the wiring. You can see where I glued it in the picture. I also put strips of glue on areas of the LEDs, in case the sticky parts ever came off. This is how much progress I've made.

6/4/18

After spending a few days documenting my project, I'm deciding to add more to the shield. I'm going to cut out = the star, then glue it on to make the design stand out. I took the engraving file and edited it so it cuts out the star. Here are the settings I used.

The star cut out really well! I'm using wood glue to glue on the star.

6/5/18

After a bit of sanding on the extra glue, the shield looks AMAZING! I'm glad I decided to add this to the design. The only downside is that there were some stains from the glue, but they shouldn't be visible after I paint it.

That's the end of my project! It lights up well, and the straps are strong enough to support the weight of the shield. This project was a HUGE success and I'm really proud of what I made!

Here is a comparison of the first sketch and the final shield. The biggest difference is the placement of the LEDs and the switch. Other than that, the placement of the straps is exactly as planned.