Designing a Sliding Lock Mounted Enclosure #3DThursday

from Designing a Sliding Lock Mounted Enclosure #3DThursday

by Noe Ruiz

This weeks project is an upgrade to our Flora Board project. In this upgrade, the circuit is way more efficient. Two 16x neopixel rings are mounted to the tucks making sweet headlights. A PowerBoost 500C makes running a lot of NeoPixels safe and easy. The trinket is nice fit for this project. A 2500mAh lipoly battery should give you a full night carving session. The enclosure is mounted to board with a sliding lock, similar to a gopro mount.

In this segment, I’m highlighting the main features of the build that make this a sturdy enclosure that will keep the components secured and locked into place. Seeing how we make these parts give you some insight on how to design for 3d printing.

I always started off by modeling all of the components that are the project. In this project, the largest component is the 2500mAh lithium polymer battery at 48mm x 61.5mm. So I used this as a base measurement for determining the right size of the enclosure.

Reusing some components I already molded, I was able to get the project finished faster. They are available on our 123D Project to customize and use in your projects.

Using a primitive cube, I created the enclosure at 56mm x 66mm x 17mm with a thickness of 2mm. This allow enough clearance for the Trinket, PowerBoost 500C and 2500mAh battery.

Using the ‘clear glass’ material option is a big help when modeling enclosures with components inside. This way you get an x-ray view of all the intersecting parts.

The sliding lock mount is two piece design that’s similar to a GoPro mount or a backpack strap clip. Two legs are setup with triangles on the ends that aree pinched inwards to allow the clip to slide into the mount.

I found this to be the best way to mount the enclosure to the bottom of the board because I’d like to be able to remove the enclosure easily for recharging the battery and reprogramming the trinket micro-controller.

These edges extend out past the rest of the clip part and have rounded corners to allow it to slide into the mount with minimal friction. It’s a bit rough to slide in and out but there’s a strong hold and I don’t suspect the tolerance will wear out too due to the thickness of the parts.

There’s wings on the side of the clip that keep the part secured to the mount. If these fixtures weren’t there, the clip would easily come off when lifted from the top.

The mount has overhanging top edges that keep the clip part secured in place. Those wings on the clip are held down by these overhanging fixtures.

To mount the clip to the sliding lock, position the clip into the mount and pinch the two legs together and push the part through. To remove the clip, pinch the two legs together and pull the part out. A lot like a belt clip or GoPro mount, right?

On the bottom of the clip, a channel is subtracted along the center to make the part slide along the railing of the mount.

The center of the mount has a railing that keeps the clip on track when slid into place.

The locking clip has two end stoppers that keep the part from sliding past the mount.

The walls on the side of the mount stops the clip from being pushed out too far.

The clip has tall edges on the legs to allow for your fingers to easily grab hold of the part to pinch them together.

The clip is mounted to the enclosure with machine screws. Two cylinders on top of the clip have a radius of 5mm that are 4mm tall with 3mm holes. The bottom of the clip has two cylinders that have similar dimensions but are subtracted to allow the screws to thread through less material.

The mounted holes on top of the clip are chamfered to minimize overhanging issues while 3d printing.

The enclosure has 4 square boxes with cylinders on each corner with and a cylinder in the middle. These are used to create an area for adding mounting screws.

With the boxes merged to the enclosure, the cylindered are subtracted to make mount holes for screws.

The Trinket and PowerBoost 500C are position onto the cover. I wanted them to be secured to the cover with machine screws so they don’t move around inside the enclosure. I positioned them so that the USB ports are accessible once inside the enclosure.

An array of cylinders are merged to the cover and used to create risers that will evaluate the PCBs from the surface, allowing clearance for any excess wiring, terminals or solder.

Another series of cylinder are subtracted from the cover for mounting screws.

I applied a chamfer to each edge of the holes on the bottom of cover so the machine screws are flush with the surface of the part.

The enclosure needed to have a hole for the mini USB port on the trinket. Most USB cables have larger handles than the metal usb connector, so its good to measure it one calipers and add a bit of padding.

Similarly, the enclosure needed a hole for the micro USB port on the PowerBoost 500C that allows charging recharger batteries.

I wanted to be able to quickly disconnect the enclosure from the neopixels so I needed to make a opening to allow wiring from the Trinket to be exposed. The slit allows me to remove the trinket from the enclosure without having to unsolder the wiring.

Slide switch adapter is on the opposite side of the hole and I was able to reuse the slide switch widget we’ve used in many other projects. It’s a great drop-in widget.

Overall this enclosure is a much better design than the previous Flora LED skateboard project. The parts in this project are available on to download on Thingiverse and 123D Design.

If you’d like to build or remix this project, check out the guide on The Adafruit Learning System for the full tutorial.

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Every Thursday is #3dthursday here at Adafruit! The DIY 3D printing community has passion and dedication for making solid objects from digital models. Recently, we have noticed electronics projects integrated with 3D printed enclosures, brackets, and sculptures, so each Thursday we celebrate and highlight these bold pioneers!

Have you considered building a 3D project around an Arduino or other microcontroller? How about printing a bracket to mount your Raspberry Pi to the back of your HD monitor? And don’t forget the countless LED projects that are possible when you are modeling your projects in 3D!