Special Project: Coffee Shoppe Chumby
TIME: 18 HOURS ** COST: $206.11** ** DIFFICULTY: DIFFICULT** ** PARTS** (1) Chumby latte (Chumby #CHLATTE3NXXXX; $179.95) (1) ¼-inch x … Continued
TIME: 18 HOURS
(1) Chumby latte (Chumby #CHLATTE3NXXXX; $179.95)
(1) ¼-inch x 2-foot x 2-foot sanded pine plywood (Lowe’s #7701; $3.00)
(1) 3″ leaf pewter handle (Lowe’s #140443; $4.97)
(1) Momentary SPST switch (RadioShack #275-609; $3.39)
(1) 4 oz Titebond II wood glue (Lowe’s #218256; $2.34)
(1) Semi-Gloss spray polyurethane (Lowe’s #45873; $5.97)
(1) Daily newspaper (local purchase; $0.50)
Hookup wire (RadioShack #278-1223; $5.99)
Remove the exterior leather trim from Chumby. There is enough synthetic
batting inside this critter to make a quilter green with envy. Gently
pull the leather away from the plastic screen bezel and the rear
Remove the rear speaker plate from the speakers and Chumby daughter
card. The speakers are held in place with some glue and the daughter
card is attached to the plate with a couple of screws. There are three
printed circuit boards (PCBs) inside Chumby: the main PCB, a daughter
card PCB, and a riser card PCB. The daughter card contains the Chumby
USB, power, speaker, and switch interfaces. The riser card holds the
USB Wi-Fi card.
Step 3.** Convert Chumby to battery power. This step might
already be done for you! Our Chumby came equipped with a 9V battery
snap connector already installed and ready for use. [This feature was
included as a Chumby backup power source for use during power outages.]
Unlike the stock power-cord Chumby, don’t expect to run Chumby from
this 9V battery 24/7. Rather, under battery power, you can turn Chumby
ON for gathering your news, weather, scores, and blog hits, then turn
it OFF for conserving battery life. In order to facilitate this regular
ON/OFF power cycle, add a SPST momentary switch (see Step 4) to the
outside of your new Chumby. Then press the switch to power ON Chumby,
read your info feed and press the switch again to power OFF.
Step 4.** Solder two wires to the Chumby main power switch on the daughter card. This is very delicate work with tight pin placement. These wires will be connected to the momentary SPST switch in Step 6.
Build an enclosure for holding the Chumby PCBs. I made a five-sided
(the bottom was left open for easy battery removal/replacement) plywood
box. My overall dimensions were: 5 ½- x 4-inches (front and back), 2- x
4-inches (two side panels), and 5 ½- x 2-inches (top panel). Cut an
opening for the touchscreen LCD in the front panel. Sand the opening
for a rounded edge. Glue four panels together: front, both sides, and
Mount all PCBs, speakers, and the LCD inside the box. Mount the
momentary SPST switch on a side panel. Solder the two switch wires from
Step 4 to the momentary SPST switch. Glue the back panel in place.
Finish the exterior with newspaper glued over the plywood base. Finish
the newspaper with several coats of polyurethane.
** Eh Voilà:** the finished Coffe Shoppe Chumby. **
In this portable configuration, the 9V battery can be drained even when
Chumby is OFF. Remove the battery when not using Chumby. Also, too much
pressure on the touchscreen LCD during installation can result in
Chumby displaying a “Special Options” screen. This screen can be
dismissed in a couple of seconds.
This hack does not prevent your Chumby from hooking back up to AC-power when not out on the town—simply modify your enclosure to accommodate the AC cord if you desire.
And finally, we have created a special Chumby Flash Widget. Use this Widget for reading an RSS feed from the How2.0 Blog. —Dave Prochnow