I just came up with an idea for completely replacing the most problematic part in the sega cd model 1 - the door closed switch.
Its a leaf switch that closes when a pin on a gear pushes up against it. Problem is that the pin just barely pushes up against it.
the door open switch isnt nearly as much of a problem because when the tray is open it is slammed against the switch as far as it can go.
here is my solution using a long arcade lever switch.
If you bend it just like that it will make contact with the back of the tray and can be bolted on top of the bios board cover.
these are the points to solder to. there are two points right underneath each leaf switch. and door closed would be the ones to the right.
this will replace that pita switch with a switch that is many times more reliable.
I havent worked out the door open switch yet but i rarely have problems with it because it seems to make better contact because it gets pushed further.
I will post some more pics when i get this wired up.
EDIT: my first attempt at this was a failure because the top cover wouldnt close. Ive since bent up the side of the cover and moved the switch underneath and bolted it to the underside. its hard to believe but the screw on that corner still holds the cover down with it bent like this.
i also have an idea for just bolting a pushbutton to the metal frame at the back of the tray which would be even better. id have to make a bracket for it though.
BACK to the drawing board. None of this is going to work because even though the switch is being pushed when the tray is closed there is still the motion of that gear that hits the switch that occurs after the tray is closed. the timing on this idea is way off.