Introduction: Bunk Bed With No Screws
Here's a project I've been working on during my spare time for the past ~two years. It started off as a simple Tinkercad prototype which was printed as a scale model on a MakerBot Replicator 2 for testing purposes. The idea worked great, however development was put on hold. Project finally resumed at the end of 2017 when the family grew yet again and the kid's room required a makeover.
A common pattern when thinking about furniture design is using screws/bolts to fasten things. This got me thinking if there was another way, a way which requires no fasteners – just simple design thinking.
The bed was designed around three main constraints:
- the crib mattress size (52"×28"×7"),
- tight space the structure must fit into (72" in length) – with 1/4" of clearance on each side, and
- ability to be cut out of freely-available materials – a standard 3/4"×4'×8' panel was selected for this reason.
I wanted to cut out as little material as possible out of the side panels to keep them as strong as possible... I wanted to be sure it’s the safest it can be for kids. To commemorate the location of where this bed was designed, the top panel actually resembles Golden Gate bridge – the first bridge you see as you enter the Bay, and the oldest one, just like my oldest son (where he sleeps). Bottom one is the newest portion of the Bay Bridge – it is elegant and not as old as GG bridge, just like my younger daughter.
The beauty of this idea, however, is that one could truly customize their bed with anything from child names, to other, more complex/intricate designs. I wanted to keep with the super minimalist style for v1.
Another added bonus of this design is that, unlike most bunk beds on the market, it can be easily mirrored, meaning you could have the steps either on the left or the right side just by flipping a single panel! Speaking of stairs, they were integrated for extra storage (can fit 12" books standing upwards) and at the same time greatly increase the overall strength of the bed structure. Addition of books provides for added weight, which attributes to added stability of the bed. Initially I had designed the bed to feature drawers, but due to the recent explosion of kid's books in our library, we desperately needed the extra book storage.
You would also be pleased to know that the assembly of this bed requires absolutely no tools; only the disassembly requires pliers (for safety reasons).
Now, unless you go out of your way to try and disassemble the bed, it will stay in-place without any problems. That might not be the case with kids, however. My children dismantle anything and everything, so it was important to add an extra safety layer. In the spirit of not using any type of common fasteners (bolts, screws), as well as the open design nature, I've designed a simple locking clip mechanism which can be easily 3D printed on ANY FDM (and others) 3D printer.
Speaking of safety, the bed was designed with the following in mind:
- Guardrails on both sides of the upper bunk, except for up to 15 inches at each end of the bed.
- The upper edge of the guardrails shall be no less than 5 inches above the top surface of the mattress when a mattress of the maximum thickness specified by the bed manufacturer’s instructions is on the bed
(7" in this case).
Guardrails shall be attached so that they cannot be removed without either intentionally releasing a fastening device or applying forces sequentially in different directions.
- That openings in the structure surrounding the upper bunk be small enough to prevent passage of a tapered block having a base measuring 3.5 inches by 6.2 inches.
- That openings in the end structures and the FHSA rule addresses hazards associated with bunk beds intended for use by children.
The rules are issued under both the Federal Hazardous Substances Act (FHSA), for bunk beds intended for use by children, and the Consumer Product Safety Act (CPSA), for bunk beds not “intended” for (but often used by) children. These rules came into effect on June 19, 2000 and apply to all bunk beds manufactured in the United States, or imported.
But yeah... Use this bed at your own risk!
Best place to get the most up-to-date information on this open source project is the official website: www.freebunkbed.org
I should make a note that this bed is free for personal, non-commercial use. In case you have commercial ideas/suggestions, please do reach out!
Read on in case you're here to know how to build one for yourself!
Step 1: Materials
As previously noted, this bed was designed to be as accessible as possible (in every meaning of the word), and as such, you will require 5-6 sheets of standard 4'×8'×3/4" plywood. Why the range? Initially I've designed the bed to fit 5 sheets - the most cost-effective way to build it. After examining the bed design, my friend recommended that I add an extra support for the top bunk, which was a fantastic suggestion, and is currently how my kid's bed is set up. With that in mind, the top bunk with support can hold anywhere from 150-250ish LBS, while without support it can handle up to 150(ish) LBS. You guessed it. If you want your top bunk to have extra support, prepare to use 6 sheets of plywood. Cut it out and experience it for yourself. [The bed can easily handle adults, given they can fit].
Depending on your budget, the cost of plywood can be as little as $20-50/sheet, and go into several hundred dollars per sheet. Initially I was planning on using Russian 11-ply, however right before cutting the bed, decided to switch to a local USA-made 7-ply maple, which ended up working just fabulously! This was in the range of $60-70/sheet, or $360-$420 for 6 sheets.
BONUS: in case you'd like to build the miniature version (a scale model) of this bed, feel free to download the SVG file. As seen in STEP 1, it can be cut out of various materials, so you'll have to manually scale the file depending on the thickness of your material. This can be a great addition to any doll house or a [useful] showcase piece which could be used for storing essentials such as keys and wallets! Check out the laser cutting class in case you're interested in this version of the bed.
Step 2: Cutting
This bed can be cut out with any ShopBot/CNC that can accommodate 4'×8'×3/4" sheets of plywood.
Check out the many photos here to get an idea of the process. The CNC we used was quite incredible, actually, and, unlike ShopBots, where you have to clamp everything down, this one was using a powerful vacuum system to hold the sheet in-place. This reduces the work by at least an hour, I'm assuming... I won't get into details of how to use a CNC - there's actually a class for that, so all I'm going to say is that you can grab all the files from here. Be sure to create dog bone fillets, otherwise you'll have issues with assembly.
Once cut, you should consider rounding all of the sharp edges - my wife/kids appreciated that little big detail. Use the 3/8" round over bit for that.
Step 3: Finishing
If your plywood came finished on both sides, all you'll have to do is round off all the edges for best usability experience using a router, and then thoroughly sand all the edges. The better your sending job, the longer your bed will last.
In case your plywood came finished only on one side - like mine - you'll have to manually stain the other side. I got recommended this BeesWax product by a friend who is very particular about the products his kids come in contact with, so rest assured that this has been deemed very safe for child use. It also makes your room smell nice for the first couple of weeks! :)
Be very thorough in your staining as bed's lifespan greatly depends on how well you protect otherwise exposed wood. One bottle covers single bed.
Step 4: 3D Printing
This step is required in order to complete your bunk bed. Head over to the downloads section and grab 3D printable STL files for clips that are used to secure all panels in-place (to prevent them from coming out).
The idea, just like the bed itself, is very simple:
- Insert panel.
- Slide panel down.
- Insert clip into the remaining opening to secure it in-place.
See the attached diagram for more detail.
Depending on how dark your wood is, there are two options of PLA filament you can go with. See attached photo of the darker locking clips, and lighter clips that hold LED lights (I prefer MakerBot filament for its consistency/ease of use).
Be sure to check out the official Store section in case you're interested in some 3D printer recommendations.
Step 5: Assembly
Be sure you have the 3D printable assembly clips before proceeding with the assembly of your bed. (Check the previous step for more info.)
Assembly of this bed is meant to feel more like an enjoyable puzzle, rather than instruction manual-referencing-fastener-selecting torture, that furniture assembly is turned into most of the time. In fact, the assembly is so intuitive, that most of you won't require a manual in order to "solve this puzzle".
Perhaps I will get around to creating a dedicated manual, but for now, please use photos included throughout this Instructable to get an idea of how the bed comes together.
Step 6: Accessories/Add-ons
Besides the ability to add ambient, energy-efficient LED lighting to the bed itself (as seen in the photo), as a bonus accessory, the bunk bed design includes two night tables, which could be made spill-resistant by creating a 1/2" groove using a round router bit (see photos). My kids love them!
In case there's enough interest, I'll consider releasing several other add-ons that make your bed even more useful!
Step 7: Enjoy the Zzzz's!
We have a be nice policy.
Please be positive and constructive.
Could you replace the 3D printed parts with small wedges cut from the same wood. You could sneak them into areas that would otherwise be scrap. This would reduce the number of materials needed and reclaim some of the waste. Combine that with the Maslow CNC and you have a pretty powerful design that could be utilized in areas of need.
- I wanted the project to be as little labor intensive as possible. You could cut out the clips which secure the bed together, but you'd need to create a way to get them out once they have been pressed into the bed. 3D printed design allows for that to happen by incorporating two small holes, just big enough to fit the ends of [needle-nose] pliers (so that the clip could be pulled out). You would have to most likely drill to create these holes. If you drill in such a small piece of plywood, there's a high chance that the whole thing will either fall apart, or start to lose some of the sandwiched boards, compromising on its strength.
- Plastic is a bit more forgiving/flexible. Clips are designed to get wider towards the end, so they don't easily slide out.
- Most will want to attach the lights too, at that point you'll definitely have to 3D print the attachment clips, as there's currently no elegant way of attaching the lights without them.
- ...And if you've already established a system that works, why not share it with other potentially similar in their purpose/use components?
- Plus, 3D printing is AWESOME!!! ;)
You're absolutely right - that could be invaluable! Will definitely consider a plywood-only design in the future version. I actually just wrote a comment regarding why I chose to go with 3D printing in this case. It's the long one just a few comments below this. Take a look.