So I've been having some keyboard problems, and Planet helpfully sent me a replacement keyboard. It turns out, however, that the keyboard is essentially the entire lower half of the unit, and replacing it necessitates complete disassembly of the lower half. This proved to be an interesting little adventure, which IRC user Steve-Goodey encouraged me to document. Unfortunately the only camera I had was the Cosmo itself - so sadly no pictures, apart from this one of the back of the replacement (we all know what the front looks like):
https://imgur.com/a/XeDhsj4 Without further ado...
COSMO COMMUNICATOR LOWER HALF TEARDOWN
Pull the back off by prising under the hinge side. Fingernails more or less work for this. Note that the back has tiny locking tabs - these go on the hinge side. Place the Cosmo face down, with the hinge on side furthest from you.
Remove the two end caps - they are held in by 3 and 4 retaining screws respectively.
SMALL PARTS WARNING: the little silver button.
Remove all the battery retaining plate screws but leave the battery in place.
There are two small ancillary boards, one on each side. Each board has a retaining plate to hold down the ribbon cable connectors it accepts. The right hand one accepts the power cable from the battery.
Remove the screws holding down the battery connector retaining plate. Gently disconnect the battery by prying up the connector.
You may now remove the battery and plate (on my unit they are stuck together with adhesive).
Removing the ancillary boards: nothing fancy, just remove the screws. All ribbon connectors are of the vertical insertion type, except the keyboard ribbon. The keyboard ribbon cable connector is of the type often used in laptops - horizontal insertion with a locking flap. The keyboard ribbon is the only ribbon cable that does not go into the screen, but loops over the top and out of sight. It is on the upper left.
SMALL PARTS WARNING: there are two tiny silicone ducts, one on each end of the Cosmo, underneath each ancillary board. They lead into a pair of MEMS microphones. They are easy to miss and easy to lose. Also, when putting them back, make sure the duct leads in to the microphone! It's possible to install them upside down, and you'll probably get muffled recordings if you do.
To completely seperate the two halves of the Cosmo, first gently peel all ribbon cables (except the keyboard ribbon cable) away from the surface. It doesn't take a huge amount of force, but try to pull vertically, not laterally. There are three hinges on the Cosmo. The middle one has a seperate subassembly which is screwed to the base with two screws. NOTE: These are the only screws which are different in the entire lower assembly - they are slightly longer! To remove the side hinge rods, gently pull with needle nose pliers. You might find it easier with the unit open. To full seperate the halves, disentangle them from the hinge spring by fully opening and unhooking the spring from the base.
Naturally, reverse the process to reassemble. Some screws go through multiple parts - it's helpful to stack the parts up "dry" so you don't put screws in too soon. And when you stick the ribbon cables back down, make sure you give them enough slack when the unit is fully closed.
Before I started I was quite afraid of putting my Cosmo under the knife, but actually it's quite a forgiving product to disassemble. Hopefully I haven't skipped any steps, as I wrote this from memory after the fact. Hopefully this helps anyone wanting to disassemble their Cosmo for some reason!
And the new keyboard is magnificent. Thanks, Planet!
EDIT: linked picture attached to the post. Varti
