First off, peel the masking off all your laser cut parts.

Next, you'll mount the BeagleBone to the bottom using 14mm M3 bolts, M3 nuts, and 1/4" OD 1/4" high nylon standoffs.  Make sure to mind the resistors on the back side of the board around the power connect (labeled R150 and R189).

Next, you need to partially thread all the remaining M3x14 bolts into the T-slots of the spanning pieces and the end caps.  This is physically possible without assistance, but it's hard.  You'll want to save yourself some time by using some scotch tape and securing the nuts in place before inserting the bolts.

Once this is done, you can slide in the bottom, sides, and top before finally tightening down the bolts.  Don't overtighten the blots, the enclosure is all acrylic and it will crack under extreme stress.

Bottom Installed

Sides Installed

Top Installed and Bolts Tightened

Other Side After Assembly

You can simply leave the top off if you want easy access to the expansion headers.  The Adafruit BeagleBone proto cape will even fit with the top off:

Here are some additional pictures of the enclosure with the USB host and peripheral interfaces plugged in (notice that you can see the status LEDs above the peripheral connection):

Grab an enclosure kit including handy hex wrench from my store and you can grab all the design files and BOM from the Thingiverse entry.

You can grab a sled kit there as well, if you feel like your BeagleBone would like a little more of an open air prototyping environment. You can find the design files for the sled, BOM, and instructions on its Thingiverse entry here.

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Above is a picture of a recent project I did for a client that wanted a custom enclosure for some experiments with mice. It's constructed from laser cut ABS sheets and held together with screws, but it doesn't use the now somewhat ubiquitous T-slot construction used in many laser cut enclosures.  Because ABS isn't extremely brittle like acrylic and doesn't have a grain or laminate layers like wood, you can simply screw it together without significantly effecting structural integrity if you do it right.

I first used the method I'll be outlining here to construct a "dark box" add on for a piece of lab equipment.  It had to fit very snugly inside an existing box, not let light through, and not provide climbing holds for the mice under test.  I didn't want to end up gluing everything together (I'm glad I didn't, I had to modify the setup for an additional experiment later), and T-slot and bracket based attachment methods were not ideal.

First off, in my enclosure design I've added tabs to ease alignment of all the connecting parts.  If done correctly, tabs will prevent you from assembling your enclosure incorrectly and allow you to quickly align edges of parts you're screwing together.  Tabs also allow you to insert screws into both of the parts you're joining perpendicularly, which a regular butt joint wouldn't allow you to do.  I use 1/2 inch #4 flat head sheet metal screws for 1/4" ABS.  I drill a 3/32" pilot hole is drilled into the parts that will be joined.  Pilot holes are a must, as you can drive a screw in to ABS with a little work, but you'll see stress lines and bulging, if not outright splitting of the plastic if you don't use an appropriately sized pilot hole. I place the pilot holes at design time and cut them into the part so I have a nice guide when it comes time to drill.  Here's an example of a part with tabs and pilot holes in place:

To make sure I hit the correct depth, I add some tape to the bit to let me know I've drilled far enough into the piece.

I use right angle clamps to hold the parts I'm joining in place while drilling.

Here's a close up of the tabs and pilot holes after they've been drilled:

Next I countersink the holes and install the #4 screws:

You can prep and screw a side together relatively quickly with a little practice.  Once you've got a few sides on your enclosure, you can rely less on clamping parts together and simply hold down the panel you're installing with  one hand while drilling with the other (assuming you've added tabs to your parts so they align properly and stay in place).

Here's some pics of the finished product:

I've also used black oxide coated screws with this method to make the final enclosure look a little cleaner as well.  Overall I like the look of this method over T-slot construction for some projects since you don't have to oversize some parts to accommodate the tabs and screw holes and the joints seem a little sturdier as well.

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PE00001 - First Stage of Construction

I’m hoping to overcome MakerBot Industries’ understocking problems by making some slightly modified motor controllers and using some alternative drive components, but for the most part I’m sticking to the design that they’ve laid out for my first foray into 3D printer construction.  I’ve got all the parts I need for the body cut and all the parts I should need from McMaster Carr already, but still need to get the parts for the extruder and drive system cut as well as order all the parts I’ll need from SDP-SI.  SDP-SI seems to be out of a number of needed components as well so I’ll likely end up experimenting a bit with alternative drive system.