Introduction: Tetris Bookshelf
In honor of the longstanding tetris rivalry between members of the instructables staff, I designed a set of tetris bookshelves for the instructables office using Autodesk AutoCAD and new preview version of Autodesk 123D Make. These shelves are great because they can be rearranged and stacked anyway you like, and you can always make more if you need them. I used a laser cutter to cut the shapes out, making the whole process quick and minimally labor intensive.
Step 1: Modeling in AutoCAD
The tetris shapes are fairly straightforward; each piece is made of four unit pieces arranged in seven different orientations. Since I chose to make my shelves without a back panel, the S and L shaped pieces can be flipped over to produce their mirror images. This means that I only needed to make 5 types of pieces.
I modeled the shelves in AutoCAD by drawing the shapes in 2D, extruding them into 3D and subtracting the inner volumes. The final shelves will be made from 3/4" plywood, with each unit piece measuring 9" inner diameter and 10.5" outer diameter. The depth of the shelves will be 15". For now I've only built a prototype set which has been scaled down by 1/3 and cut from 1/4" plywood. I exported these shapes from AutoCAD as a single stl file to send to 123D Make.
I've attached the dwg and stl files for both the full sized and scaled versions of my tetris shelves.
Step 2: Send to 123D Make
I imported the stl file into 123D Make, a free app that lets you prepare your 3d files for laser cutting. I'm using a new preview version of 123D Make that is not available to the public yet, so I had a lot of control over the type of joints to use for my tetris pieces. The public version of 123D Make will be getting regular updates in the coming moths, so hopefully you will be able to use these features soon too! In the meantime, I have attached my 2D vector files (eps files) for both the mini prototype and full sized tetris pieces.
In 123D Make, I set the joint type to finger joint with 12 fingers for each joint. I specified the dimensions of my material and 123D Make created 2D vector files with the correct finger size and fit them onto sheets for laser cutting.
Step 3: Cut and Assemble Pieces
I sent eps files from 123D Make to a laser cutter and cut them from 1/4" plywood. If you do not have access to a laser cutter or cnc cutter, consider using an online fabrication service.
I removed all the pieces and inspected the edges, some needed additional sanding/finishing. I separated the pieces by size (there are 6 different lengths) and compared them to my 123D Make model. To be safe, I assembled my tetris pieces without glue first.
Step 4: Gluing Pieces Together
I applied wood glue to the joints, assembled the tetris shapes, and clamped them together to dry. For best results, use a corner block to clamp all joints to exactly 90 degrees.
Step 5: Finished Product
Once the wood glue dried I removed the clamps and the five tetris prototypes were done! At this point they could be stained or finished depending on what you like.
More to come when I finish the full sized shelf set...

Participated in the
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1 Person Made This Project!
- arsalanhn made it!
25 Comments
10 years ago on Introduction
Thanks, Amanda. I was ecstatic when an update for 123D Make was released this week. Little disappointed when I had to update Mac OS X to be able to get it. Even more disappointed to see that it still doesn't have the plate function. The only new construction technique is Folded Panels, like for sewing or riveting.
If you have ANY influence with the developers, PLEASE encourage them to make this awesome function public.
Or just send me your preview version. I mean it's a free app, right? Same username at gmail. ;)
Reply 10 years ago on Introduction
I will do my best to get it released :)
Reply 6 years ago
Still not unavailable :(
Reply 7 years ago
Do you take orders?
9 years ago on Step 2
I like the instructable, but I am wondering where I can get my hands on the copy of 123d Make that allows finger joints for construction?
Reply 9 years ago on Introduction
that's not released yet unfortunately, I'm hoping it will be out soon
9 years ago
Super awesome! It would be cool if you made them all the djfferent tetris colors!
10 years ago on Introduction
123D Make app came out on Feb. 4th! I see it in the App store now.
10 years ago on Introduction
I LOVE this design! Especially the laser cut "patina". I had been working on my own design (in Illustrator) but had trouble with the joint design. Then I found your ible, and through it 123D Make! So cool!
But here we are in 2013 and I don't see any way to do finger joints. I need different dimensions than you did (mostly the depth), but as far as I can tell I can't set up those finger joints as you did. Am I just missing something? Or is it still just vaporware for the rest of us? :(
If I could use this program to design boxes, especially speaker boxes, I would be so happy! Until then I'm very sad, because it feels like you're teasing us. :'(
Reply 10 years ago on Introduction
ah, I'm sorry, I thought it would have been out by now, but it's not unfortunately. I'll definitely let you know if I hear anything about it going live.
10 years ago on Introduction
Hello.
How did you get your hands on the new preview version.
11 years ago on Introduction
I have access to a laser cutter but not autocad. Any idea if these files can be imported into Inkscape?
Reply 11 years ago on Introduction
No, but GIMP will open the EPS file that Amanda included in step 2. From there you can save it as a DXF for use in Inkscape.
Reply 10 years ago on Introduction
Thanks for the tip! I'll give that a try!
11 years ago on Introduction
Want. Definitely adding to my long list of build projects.
11 years ago on Introduction
Nice! How are you going to cut the joints on the big ones?
Reply 11 years ago on Introduction
we're going to be using a very high power laser cutter
11 years ago on Introduction
Just a question, how stable and strong is this design in practice? I love the concept but some of the pieces look like they may sag under the weight of books and more robots. Maybe applying some backing material to ensure the pieces retain their shape would help?
Reply 11 years ago on Introduction
The 1/4" plywood pieces are actually pretty stable, I guess it depends on what you plan on storing in them. Yes applying backing material would help, we decided not to do this bc we like the way it looks without. The set pictured here is pretty small, not really large enough to put books in. We plan on making a larger version with 3/4" plywood, so we're hoping that the larger joint surface area and stiffer wood will help out with stability. I'll keep posting as the project progresses!
If there's interest I could model the set with backing, compute the finger joints on 123D, and post the eps files.
11 years ago on Introduction
Great Stuff!