[Nexus 7 Accessories] l3iggs:
Hey everyone, I've grown tired of waiting for Asus/Google to release a dock for my nexus 7 so I built one myself. I'd like to share my work with you all.

I cut my dock out of 6.0mm thick acrylic with a 30W CO2 laser. Cutting all the pieces for one dock takes around 9 min on my machine (more watts=faster cuts). If you have access to a laser this is a very easy job. Maybe you could go use one at your local tech shop or something. The dock consists of 5 pieces that snap together and stay that way by virtue of friction. You could probably cut this design out of wood instead of plastic like I did here. That might look kinda cool.

I bought the acrylic sheet I cut the pieces out of as scrap from a local plastic store (TAP Plastics) for US$1.

The pogo pins I used are manufacturer part# 0933-0-15-20-75-14-11-0 made by Mill Max, purchased from newark.com for $1.20 each. I use bluetooth for audio so I didn't wire up the two middle stereo out pins, so my BOM comes to a grand total of US$3.40. I'm happy with the result for that price.

The dock works great. The device recognizes the dock and begins to charge first time, every time I seat the device. I've tried to avoid blocking any of the speaker grills, plugs, microphones light sensors and cameras. Unfortunately my dock does kinda block the ambient noise microphone that's right next to the pogo pin pads (stupid spot to put that).

For now I've just soldered pogo pins 1 and 4 to a 5v charger I had laying around. So charging works great.

EDIT: I'm working on making a PCB that supports:

-- stereo audio out via 1/4 in headphone jack

-- Micro USB B connector for charging

Stay tuned here for an updated parts list and schematic and PCB layout files.

As reported elsewhere on the forum, I can confirm that the device stops drawing current via the pogo pins when a USB OTG cable is plugged in (although the device still indicates that it is charging in the menu bar, seems to be a bug). So pogo pin charging while using USB OTG seems to be a no-go (pun intended!). Update: this may be fixable with a modified kernel.

I expect a 1st party dock will come out very soon since the OS software is now ready for it. Several of the features added by recent updates seem to be aimed directly at dock mode (Daydream, portrait home screen) and they work great (the daydream screensaver auto-starts properly when docked).

I'll attach some pictures of the docks I made. I made 3, two out of white and one out of black plastic. I like the black one better although the glossy acrylic in black is a fingerprint magnet.

I created the design files using the free Autocad clone software called Draftsight. I'll attach it here so anyone who wants to can get out and cut themselves a charging dock for their favorite tablet. The units for the drawing are mm. The drawing format is autocad 2010 ascii dxf.

If you do try to use my design to cut your own dock, be aware that the tolerances on the two curved side pieces are very tight to ensure that the other three pieces fit in snugly enough to hold everything together. If the cut width for your laser differs greatly from mine, you might end up with a dock that doesn't snap together or one that is loose and falls apart. Don't say I didn't warn you! In the case your dock doesn't fit together properly, you can make some very simple tweaks to the inside cuts on the side pieces to get things to go together for your laser.

The design will need some major adjustments if you use anything other than 6mm thick stock. The holes in the side pieces will need to change as will the width and possibly position of the slot in the cradle piece.

Be aware that it's actually pretty easy to put the dock together incorrectly (design flaw). There are 4 assembly possibilities that change the locations of the pogo pin holes, three of them are wrong. You'll figure that one out easily enough. The one that is tricky is the cradle piece (H-shaped piece) which is basically two rails that create a slot between them that the device rests in. If you look closely, you'll notice that the slot is not exactly centered in the piece making one rail ever so slightly thicker than the other. The thinner rail should be towards the front of the dock (there are only two ways you can assemble this part so you have a %50-%50 chance of getting this wrong if you're not careful here). If you get this wrong the device won't lean up against the back rests so it will be very unstable and will sit very awkwardly in the dock.

Cheers!

p.s. I'm happy to help anyone out who wants to try making their own dock. Ask away and I'll do my best to answer any questions.