Introduction: Bear Coin Bank

About: The FabLab at Ball High School campus is fully equipped MakerSpace with a Universal Systems 60W laser cutter, GlowForge laser cutter, OtherMill CNC milling machine, Ultimaker 2+ & 3 3D printers, MakerBot R…

Some friends of mine have a daughter and when I see her she's always giving me coins she finds on the ground. Her birthday was coming up so I decided to make her a coin bank that looked like a bear since she likes bears. I wanted to try using the ShopBot CNC with cedar. I like working with cedar and it lasts a long time and has a nice smell. The body is cut from two pieces of 1.75" cedar and then glued together. I used the ULS 660 laser to engrave and cut a piece of scrap plexiglas to make a cover. The cover is held in place by really strong neodynium magnets.

Supplies

VCarve Pro or Carbide Create

Adobe Illustrator or CorelDraw

CNC

Laser cutter

Jig saw

1.75" x 7.75 x 12" cedar board

Wood glue

Plexiglas

Magnets

1/4" x 2" downcut end mill

1/2" upcut end mill

Sandpaper

Superglue

Step 1: Draw Your Design As an Outline

I first started off by drawing a bear outline with Adobe Illustrator and included a belly, eyes, nose, mouth and made the legs even on the bottom so it will stand up.

Step 2: Save Vector for Export From Adobe Illustrator

Next I exported the vector for Export as .dxf, .dwg, .eps, .ai or whatever your software requires. I used .dxf since that's what VCarve likes to import.

Step 3: Create Toolpaths in CNC Software

Next I imported my .dxf vector into VCarve Pro so that I can apply toolpaths for the ShopBot CNC to cut. I exported each toolpath separately because I like to be able to intervene if something goes wrong during the cutting. I used both 1/2" & 1/4" flat end mills (FEM)

I created the following toolpaths based on my 1.75" x 7.75" x 15" cedar stock

I ran the 1/2" FEM first with these:

-Coin pocket 1/2 FEM cut all of the through to 1.7499" on the front piece of the bear

-Back pocket 1/2" FEM at .50" depth

-Coin slot 1/2" FEM at .20" depth (this is the slot where the coins can slide down)

Then changed the tool out for the 1/4" FEM and ran these:

-Eyes 1/4" FEM cut to .50" depth

-Mouth 1/4" FEM at .50" depth

-Nose 1/4" FEM at .50" depth

-Inset cover 1/4" FEM at .20" depth (this is where the plexi cover will sit just below the surface)

-Outline cut out of each piece 1/4" FEM at 1.7499" depth with 3 tabs on each piece

Step 4: Set Up Your Material for Cutting

I took my 1.75" x 7.75" x 15" cedar board and clamped it down on the spoil board of the ShoptBot Desktop 24 CNC. I used some clamps that I got from Rockler and put one at the top left corner, lower left corner & right corner. In addition, I also used some wooden clamps that I made on the CNC to push against the middle top and right side using the inset threads on the spoilboard.

Next I calibrated the Z height with the 1/2" FEM and everything was set to go!

Step 5: Running the CNC

I made all of the 1/2" FEM cuts first and then changed tools to the 1/4" FEM for the remainder. I also double checked all of the clamps between tool changes and re-tightened them just to be sure.

Step 6: Finishing Up the Parts

Once the CNC is done I used the jig saw to cut out the tabs that I put around the front and back pieces. I used some sandpaper and a bandsaw to clean up any rough edges. I also made a 3D printed dowel sander that I made to get into the smaller areas.

After all the sanding is done I used wood glue and clamps to assemble the front and back pieces and let it sit overnight.

Step 7: Engraving the Front Cover

Next step was to make a front cover with a name engraved from plexi. I had some scrap plexi from another project so I used a small piece of that for the cover. I used the "belly" shape from the toolpaths to make the outline for the front cover and added "Evie" for the engraving.

I use a ULS 660 laser cutter so I set the cut out to .001 RGB red and the name engraving to black.

Step 8: Adding the Front Cover

Once the cover was cut out from the laser and engraved I used super glue to attach the neodymium magnets to the plexi cover and the inset.

Step 9: That's It!

Once it was all done it was time to drop some coins in the slot!

CNC Contest 2020

Participated in the
CNC Contest 2020