SIO2SD/XM301 Case Conversion 3

Entry posted by flashjazzcat April 15, 2010

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I didn't get around to blogging progress yesterday, so two days worth of updates today.

Since the LCD display needs to be rotated, I decided the cabling would be more flexible if I separated the wires and the baled them with cable ties:

Before I got hold of some LEDs, I decided to start work on the case. This is far and away the most fraught and perilous part of the job, as one wrong cut can ruin the case (XM301's are plentiful, but the supply is not inexhaustible and they're not available for free!). The tool I'm using for most of the work is an inexpensive Dremel-type made by Draper:

First job is to mark out the holes for the LCD, LEDs, buttons and card slot. I decided to position the card slot on the lower half of the case this time, enabling the PCB to be secured to the backside of the screw recesses:

The aperture for the LCD display and the holes for the LEDs and buttons are marked out on the top of the casing:

Then it's a case of drilling out the holes and using a milling bit to cut out the LCD aperture, which is then finished with a flat file and emery board.

This time, I've decided to make use of the remaining screw pillar (which I removed last time) to attach the bottom of the case and to hold the button mounting. I just noticed before cutting off the right hand pillar that it easily clears the SIO2SD board, so it seemed sensible to use it to hold the bottom of the case in place as well as to hold the button mounting. Note that I've also recessed the back of the button holes.

I used a spare offcut of plastic as a base for the bottons, and drilled a hole in the appropriate spot. The button mount (once the switches are glued in place) will slide up the screw pillar, and the switches will hold the silver button tops in place from beneath:

All cut edges, once smoothed, are then "sealed" with acetate on a cotton-bud to remove the chalkiness and restore the lustre of the plastic. The top of the casing - which unavoidably sustains the occasional mark when being worked on - is then gone over with a magic eraser, which removes the glossy patches from the acetate and gives the top of the casing a uniform matte finish.

All that remains is to cut the SD card slot, wire up and fit the buttons and LEDs, glue the LCD display in place, secure the PCB to the bottom of the unit, and screw the top to the bottom. That's a job for the weekend.