## Introduction: Custom Hexagon Shelves Using 3D Printing

We recently redid our basement as a maker space, and we wanted to add more storage while also encouraging the maker vibe we wanted. I’ve also been 3D printing for about four years, and while printing toys and figures is fun, I am always looking for ways to make practical use of my 3D printer. After a little inspiration from the Internet, I decided to make these fun custom hexagon shelves from some 1” x 8” pine and 3D printed parts. My favorite part about this design is that you can create any hexagonal pattern you want to fit your needs and your space.

Let's get started!

## Step 1: Planning Your Shelves

The first step is to plan out the pattern you want to build so you can determine exactly what your material needs will be. You can create whatever pattern you want with whatever board length you want - the flexibility of this design is fantastic! In my case, I started with the space the shelf needed to fit in, which was about 28" tall, and making a hand-drawn picture of my design.

To determine the length of each board I needed, I had to do a little math. I looked at the tallest portion of my design, the two hexes on the sides. Starting from 28", I subtracted 2.25" for the three horizontal layers of wood, that left me with 25.75" for the hexagons. I had two hexagons stacked , so each one was 12.875" tall. If you know the distance from the center of the hexagon to the edge, this handy calculator will tell you the side length you want. Under "Choose a Regular Polygon", select Hexagon, then under "Choose a Calculation" select "Find a, R, A, P | Given inradius r". The inradius is the height of the hexagon divided by 2, then look for the value of "a" in the results. I rounded to my inradius to 6.5" for my design to get a side length of 7.5". You can see my results at this link.

As you plan your design, remember you need a connector for the front and back of each intersection, so count the number of two-board intersections and the number of three-board intersections, then double those numbers to determine how many of each connector you need. For my design, I needed:

• 24 boards
• 24 double connectors
• 16 triple connectors

Later on, I decided to model the entire thing in Autodesk Inventor to make sure everything would go together the way I expected it to. This step is entirely optional, but was pretty fun to do!

## Step 2: Collecting Materials

The materials I used to make the shelves are as follows:

I decided to use the 1” x 8” select pine because I didn’t want to finish the wood right away, and the select pine comes with a pretty smooth surface. You can use any 1”-thick wood you like, but you may need to do a lot of sanding to clean everything up. For my build, 24 boards for the sides at 7.5" each meant I needed 180" of board, plus a few inches of waste from the kerf of the blade. Make sure you plan for the kerf - you'll be making a lot of cuts, and for my build, it added up to about 3" of lost wood.

Tools:

• Miter saw - Any saw would work as long as the cuts are square and straight
• Sandpaper
• Orbital sander - This is optional, but saves a lot of time.
• 3D printer
• Drill
• Screwdriver
• 1/16” drill bit for pilot holes - This self-centering drill bit worked perfectly!

If you don't have a 3D printer, you could use a print and ship website like 3dHubs or printathing.com. When I uploaded the parts, 3DHubs quoted \$4.75 for each double connector and \$6.00 for each triple connector. I have never used either website myself, so I cannot vouch for their work.

## Step 3: Cutting and Prepping the Wood

The next step is to cut all of the boards you need. Consistency is absolutely essential here, and depending on your design, you may have a lot of cuts to make. If your boards vary in length more than 1/8" or so, your final assembly may not come together correctly. I took the time to make some practice cuts on scrap lumber to make sure I was happy with my setup, and the extra time really paid off in the final product!

The best way to quickly get consistent cuts is to use a stop block with your miter saw. My saw came with a small arm that I used to clamp a scrap piece of 2"x4" in place, but you could also use double-stick tape on a piece of scrap wood or a piece of masking tape stuck to the fence of your saw. To set your stop block, bring the blade of the saw down - with the saw unplugged - and measure the distance from the saw teeth to your target length, then use that measurement to set your stop block in place.

The stop block was also essential because my miter saw only has a 10" blade, which isn't enough to cut through the 1"x8" board I was using in one go. I had to make one cut, flip the board, and finish the cut from the other side. The stop made this process quick and painless. I did have a few boards where the cuts weren't aligned well and left an edge, but I was able to sand them down and hide the edges behind the connector pieces.

After cutting all of the pieces, I sanded all of the pieces to knock down all of the edges and surfaces using 220 grit sandpaper. I did some of it by hand, then switched to an orbital sander to finish the job. In hindsight, I could have done some of the sanding before I cut the boards, which would have saved me time at this step. Also, if you wanted to stain or paint the boards for your shelf, this would be the time to do it.

## Step 4: Computer Modeling

I modeled the connectors I wanted using Autodesk Inventor, which I use for my job. Since the design was based on hexagons, that made all of the angles involved easy. Each branch of the connectors also has a countersink hole sized to fit a #6 wood screw.

From Inventor, I was able to export the files as .stl files to use with my 3D printer. You can download the files here or at Thingiverse.

## Step 5: Printing the Connector Pieces

With the .stl files ready to go, it was time to print the parts I needed. My printer is a Printrbot Simple Metal with a 0.4 mm nozzle, and each part was printed with 3 walls with 20% infill to make the vertical walls solid and as strong as possible without printing the parts completely solid. If you don't have a 3D printer, you can use a service like 3Dhubs.com or printathing.com to print and ship the parts. I've never used either service myself, so I can't address the service or the quality of the prints.

I was able to print two triple connectors or four double connectors at a time. My design called for 16 of the triple connectors and 24 of the double connectors, which used a total of about 1 kg of filament and about 45 hours of print time. My roll of yellow filament was already partially used when I started this project, and when it ran out, I switched to grey.

After printing the parts and cutting the wood, all of the materials are ready to go!

## Step 6: Assembling the Shelves

As I finished printing the connector pieces, I started rough fitting everything together. The connectors slid into place with a solid friction fit, so I basically just had to slide everything together. As you assemble everything:

• Add one hexagon at a time by putting all of the connectors in place on one side of the boards, then lay the assembly down on that face to put the connectors on the back side.
• Get the connectors snugged up against the wood so there are no gaps between the plastic and the wood.
• Be careful not to force the 3D printed parts too hard to avoid cracking them. If the connector won't go on, sand that corner of the board a bit more then try again.
• Put any connectors with print defects on the back side of the shelf where they will be less noticeable.

Once I had everything assembled, I put in the wood screws. For each hole, I drilled a pilot hole using a 5/64" self-centering drill bit to avoid splitting the wood, then drove the screws into place by hand. Be careful not to over-tighten the screws as this may cause the layers of the 3D printed parts to split - I had this happen to me on one connector. The split wasn't bad, so I took the part off, then super-glued it together using Loctite Super Glue - Ultra Gel Control. Not every super glue works on PLA plastic, but this one works with the Hatchbox filament I print with. I let the glue dry, then carefully put the connector back on and gently screwed it into place.

And that's it! The shelves look great and are extremely solid. I actually probably could have skipped the screws and just used the friction fit for the parts as I won't be putting any significant weight on the shelves, but I liked how the screws looked.

I hope you found this Instructable useful! Thank you for reading, and good luck building your own set of custom hexagon shelves!