Coffee Table Projector Hush Box

My small home projector is great, he does a good job at throwing light onto a screen in just the right way, so that it looks like people walk around on that screen, Its magic!

But, homeslice is too loud, the fan on that thing goes hard. So I built a Hush Box for him, a simple design to silence your loud projector while also keeping it safe from my kids' tiny grabbing and destroying hands.

It now lives happily in a box underneath my coffee table. Let me show you how to make one yourself.

SUPPLIES

Sheet of 15mm plywood 1m x 1m

wood glue and nails(or small screws)

high density sound absorbing panel: https://amzn.to/3omNTim
some old yoga mats or other foam

Noctua Quiet pc Fan, USB powered: https://amzn.to/34rR9lO

50x20cm flyscreen material: https://amzn.to/3B43h8A

50x20cm thin metal mesh: https://amzn.to/35PGmCl

20x10cm piece of 2mm ( or thicker) glass

black paint(optional)

TOOLS I used

tablesaw and mitre saw ( this can totally be done with a handheld circular saw as well)

bandsaw ( can be changed out by a jigsaw)

brad nailer ( can be changed out by nails and hammer)

spray adhesive: https://amzn.to/3HBMvjA

bosch 18v drill/screw gun: https://amzn.to/38fDihV

speedsquare imperial/metric: https://amzn.to/3hLyuDL

1 inch forstner bit: https://amzn.to/3B5kxu3

calipers: https://amzn.to/333toQu

paint brush and masking tape

I made a youtube video about the process as well, if you like watching instead of reading.

If you´re still reading this then I assume you prefer the latter, so welcome to the reading portion of this instructable! It´s quite the textual adventure.

The measurements were based on the space between the legs of my own coffee table, so the sizes really don´t matter. But I cut a piece of plywood for the bottom that was 85x40 cm and 6 strips of 15cm for the edges of the box. I used a box of butter waffles as a stand-in for my projector and dry assembled a box with an S-shape on the inside.

A projector is just a really hot lamp that shines light on a wall, making it look like there are real people hanging out on your wall. All this magic needs cooling and the small fan in the projector does that job loudly, so we will use science to stop the noise.

The S shape helps in stopping the sound from escaping the box. on the right side of the image an air inlet will be built and on the left the air outlet will come. The air has to go through this S shape, which is easy for air, as it gives no shits about going around corners. This is more difficult for sound, since sound has ADHD and bounces off the walls a lot, so every curve takes away some of the sounds´ power.

Then on the left side, a QUIET pc fan blows air out of the box. Creating a bit of a vacuum in the box and thereby sucking in air through the air inlet on the right.

I used a rabbet joint on the corners, giving it a bit more strength since the glue attaches to both faces. Using the fan to measure the width I cut out a hole for it to fit in. Next to the fan there was some dead space, so I decided it could be a storage cubby for the HDMI and power cable when this thing is not in use. I used a 1 inch forstner bit to cut 4 holes and then bandsawed out a square. This became the face plate for the cable cubby. Incidentally, Cable Cubby sounds like a great name for an electronics supply store.

To attach the bottom place I used wood glue and a bunch of small brad nails to hold it together until the glue dries.

Part of the reason I built this box is to keep my children's small electronics-killing fingers away from the projector so a piece of glass has to come in front of the lens and the air inlet and outlet are protected with thin metal mesh.

On the air outlet this mesh keeps their hands safe from the dangerous spinning blades of the fan and it keeps the fan safe from their dangerous small hands.

Om the air inlet I also added a piece of flyscreen mesh, to keep bugs and dust bunnies out of the box. since this inlet actively sucks in air when the box is operational.

For the lens glass I drew a line around the glas plate and used a router to cut along that line. about 5mm deep Then I cut an area out with the bandsaw that was just a few mm smaller that the glass plate. this allowed it to be inset in the box and attached with some 5 minute epoxy.

I cut up an old yoga mat and lined a bunch of the corridors with this foam. The actual sound absorbing foam is very thick and would obstruct the flow of air. So that got used only on the lid and around the actual projector. I used spray adhesive to attach them. Simply spray both surfacs, wait a few minutes until no more threads arise when you touch the, then combine. This firmly bonds both materials quite well. The combination of both these foams worked like a charm to shut up the loud projector. Then it was time to Rolling Stones this thing up and paint it black! Masking off the bits I did not want to paint with masking tape.

Under the yoga mat I added 3 small feet with holes in them these will be the points where the projector feed sit in, so if we ever bump into the coffee table it wont shake the projector around.

The quiet pc fan actually comes with a USB attachment, allowing the USB port on the projector to run it. I was obviously quite exited when it actually worked. This is fun because then the fan only runs when the projector is switched on. After attaching all the cables to the back I used a mini jack extension cable to extend the minijack port to the outside of the box, this way I can connect headphones or similar. Using calipers I measures the width of the cord, cut a piece out of the box and shoved the cable through ;)

I brought my coffee table to the workshop and let it meet the hush box for the first time. Match made in heaven. I used a few screws that held the lid in place to attach the box to the frame. Then added foam corners to the lid and placed it back on top. That is basically it. The video tutorials shows a lot more details then I can clunkily put in words, but I tried my best.

I hope you enjoyed and if you build a similar thing, plz let me know, I love reading about those types of builds.

all the best!

Love from Belgium,

Yves.