Step 3: Design: Pieces
The chess pieces are made from stacked pieces of acrylic that sweep the outlines of the various pieces. Picture 1 shows you a king.
I used SolidWorks to design my pieces. It's long tedious work, easily the most difficult and unappealing part of the project, but the pieces look pretty sweet when they're all said and done.
Step one is to rough out some dimensions. I checked all over the Internet for regulation sizes and ratios for the pieces. In general it's a bit nebulous, always ranges of values, but here's what I ended up using:
Height ratios for King:Queen:Bishop:Knight:Rook:Pawn are 27:25:25:21:18:14. I know what you're thinking, Bishops shouldn't be the same height as the Queen! Well, you're right, but I think it looks good this way, but how you do it is totally up to you.
Each piece is comprised of stacked rings. Picture 2 shows that each ring has a 0.125" inner diameter. The outer diameter will vary from ring to ring. I use the distance between inner radius and outer radius to define each ring's size. The inner hole is for the rings to thread over the 0.125" diameter acrylic rods, holding them all together and in line.
How do you actually design a piece though? Check out Picture 3, it's a snapshot of the type of sketch you should make in SolidWorks. This particular drawing is for the same king that you see in Picture 1. It shows the cross section of the king with its farthest left vertical line indicating the center of the piece. The 0.0625" dimension is the inside radius of each ring. Each of the far right dimensions corresponds to the defining dimension of picture two.
Don't add those right dimensions right away. Instead, leave those lines unconstrained in the horizontal direction. Define everything else, but leave those right hand lines unconstrained, Then, just drag them left and right until you are happy with what you see. Exit the sketch, revolve around your far left line, and admire your handiwork. If you like it, great! Add dimensions, round them off to the thousands place, and move on to your next piece. If your design needs tweaking, drag around the edges a bit more until you get what you want.
The knight is a bit special and your opportunity to get creative. It's not radially symmetric so it will need two central rods. You can do the sketch in a similar fashion except you'll be dragging bars on the left and the right. Picture 4 shows you how I accomplished it.
The rook is also a bit of a special case, it has a fancy top to make the top of a castle. You'll need to use little spokes. Check out the last image, it'll show you what I used.
But wait! You're just getting started! Doing this is just the design part, figuring out the dimensions for each ring. Now, bust out Excel, and record all of them.
USEFUL TIP FOR ONLINE ORDERING:
The top and bottom rings of each piece work better if the inside diameter is a a bit smaller, 0.12" should do it, to create a snap fit on the central rod.
Your next step is to create an individual part for every single ring. That's right, in the end you'll have over a hundred files, each a ring. I suggest a folder for each piece and a logical naming scheme. I named each part using the first letter of each piece and the number of the ring (from the bottom of the piece). For example, B_2 is the 2nd ring from the bottom of the Bishop. Ki_15 is the fifteenth ring from the bottom of the King.
Great! Now you have a ton of individual rings! And rectangles (for the knights)!
Now, drop them all into a drawing file, scaled one to one, and make sure they all fit into a 12" x 24" sheet because that's what you've got to cut them out of. Also, make sure the pieces are in order, because if you can't remember which ring is which, well, you're hopelessly lost and sad. Picture 5 is what my drawing file looks like.
Just for grins and giggles, I'll give you the numbers I used for my pieces, in case you like them so much you want to have a chess set exactly like mine. It's all in the attached Excel spreadsheet.