ааа HOME иа PROJECTS иа PEOPLEаиа BREWING и LETTERPRESS ...
juicebox
Lasercut Acrylic
Case Tutorial
Home | Up
Body
Graphics
Assembly
Finishing
Buttons
Finished Collection
   
Lasercut Acrylic Case Tutorial - Assembly
Tapping the Core
The overall assembly consist of one thin plate and potentially some side plates glued or otherwise adhered to the core, and one thin plate attached with screws. Usually I glue the front plate to the core and screw the back plate on. Having one face removeable is nice for servicing the electronics package.

Having one face attached with screws means that the core needs to have some tapped holes in it. I really like using 2-56 stainless flat head torx drive screws which you can get from Small Parts. The autocad file for the core includes holes which end up more or less the size needed for the tap. All that remains is to actually run the 2-56 tap through these holes, which must be done carefully since the core is pretty flimsy at this point. You can run the tap by hand if you are timid, but I like to just chuck it into the cordless drill and go for it.


Tappety Tap Tap

Mounting the Core to the Face
For this step, some adhesive is used to stick the core to the front plate. My typical procedure is to cold roll laminate a sheet of 3M 300LSE adhesive to the core acrylic sheet before laser cutting. This leaves a perfecly cut, aligned, and laminated piece of adhesive on the core for later. You could also probably stick the front plate on with epoxy or superglue, but we have stacks of 300LSE sheets at E Ink from an old product so I just use that. Also the stencil printing process leaves some unevenness on the back of the front plate, which I feel is taken up reasonably well by the layer of gummy adhesive. One thing to watch out for if you use sheet adhesive is to make sure the adhesive is on the right side of the plastic when you put it on the laser bed! I have cut the parts with adhesive on the wrong side more times than I care to think about; it gets tricky with things being mirrored, etc.

So I just peel off the release and line it up by eye with the front plate, bring the two together, and laminate by pressing it against a desk all around the edges.


Peeling the Release


Sticking the Front Plate To the Core

Mounting the Side Plate(s)
Next comes glueing the side plates in. These are seperate pieces cut from the same stock as the front and back plates, with graphics applied in the same way. They are designed to be as wide as the core is thick, so that when set on edge next to the core, they perfectly span the distance between fron and back sheet. The cad file for the core is adjusted to have a notch cut out or a face truncated such that when the side plate is combined with the core, it forms a solid filling in the required areas between the front and back.

When I took these photos, I was still using epoxy to mount the side plates. I like using a static mixer tip and gun dispenser for epoxy:


Freaky Needle

The glue is used to bed the side plate into its pocket in the core. Also apply glue to join the side plate to the front plate at the edge.


Snug as a Bug in a Rug

I also used to drill, tap, and countersink a 2-56 screw on each side of the side plate after the glue was set, to help hold the side plate to the core. Since the time of these photos, I have moved to using a good quality superglue like Loctite 401 to mount the plate, and have eliminated the extra holding screws as redundant.

The Back Plate
The back plate is held on with flat head screws, so the first order of business is to countersink the plate so the screwheads will lie flat when tightened.


Use a Good Countersink

Finally, assemble the plate to the core with the chosen screws and move

On to the finishing section.
Design partially original and partially ripped off from other websites
by Holly Gates