Kai Robinson
Well-known member
For now this is mostly going to be a placeholder, until the SE boards are finished, but as the title explains, this is designed to save as many Mac Classics as possible. So many have died thanks to the stupid PRAM battery on the board. These are 4-layer PCB's with a mix of through hole and SMD component. You will need at bare minimum, a soldering iron, hot air soldering station, desoldering station and a decent selection of hand tools.
So - how do you reproduce a PCB?
First, get a Mac Classic PCB - in my case a 'dead' board from Mr Adrian Black!
Then, you get to work desoldering. Literally EVERYTHING. Not a single component must remain! However, 30 year old solder and my ZD-915 desoldering station caused a handful of through holes to just pull out of the board, or some traces would come up with it. I found that pre-heating the joint, with a little flux (AmTech RMA-223), would make the solder melt a lot cleaner when you use the ZD-915 desoldering gun. You must use a lot of heat on these boards. For hot air - i recommend a temperature of 360*c and a flow rate of 4.5 - you must use the right tools for removing the PLCCS - use the A1137 and A1138 nozzles for the larger parts - and the wide round nozzle for smaller 'birdseed' and SOIC parts.
For through hole joints that have been corroded, you must flood the area with flux, heat from both sides, then try and move the pin using a soldering iron (i find 420 degrees C suitable, with a standard flat tip) before trying to use the desoldering gun. Sometimes it won't always come out of the joint, in which case reflood with flux, and attack it with desolder braid. I use 2.0mm GootWick, which is fantastic stuff (thanks to Louis Rossmann for the recommendation). Preheating the board with hot air works wonders. Speaking of hot air - for SMD parts - be liberal with flux and don't just keep the hot air on the part - you want to move it around the part, on the legs and keep a little pressue on it with some tweezers - don't force the part to move, it'll loosen when the temperature is jsut right.
You want to save basically everything bar the SCSI and Floppy connectors, ROM Socket and the 'birdseed' (SMD Resistors, Capacitors, Transistors & inductors).
Once you've saved all those parts, it's time to get scanning! 800 to 1200dpi on your scanner. As the Classic PCB is rather smaller than a sheet of A4 paper - it'll all fit without having to merge mutiple images.
There will be a more to follow...but any questions so far?
So - how do you reproduce a PCB?
First, get a Mac Classic PCB - in my case a 'dead' board from Mr Adrian Black!
Then, you get to work desoldering. Literally EVERYTHING. Not a single component must remain! However, 30 year old solder and my ZD-915 desoldering station caused a handful of through holes to just pull out of the board, or some traces would come up with it. I found that pre-heating the joint, with a little flux (AmTech RMA-223), would make the solder melt a lot cleaner when you use the ZD-915 desoldering gun. You must use a lot of heat on these boards. For hot air - i recommend a temperature of 360*c and a flow rate of 4.5 - you must use the right tools for removing the PLCCS - use the A1137 and A1138 nozzles for the larger parts - and the wide round nozzle for smaller 'birdseed' and SOIC parts.
For through hole joints that have been corroded, you must flood the area with flux, heat from both sides, then try and move the pin using a soldering iron (i find 420 degrees C suitable, with a standard flat tip) before trying to use the desoldering gun. Sometimes it won't always come out of the joint, in which case reflood with flux, and attack it with desolder braid. I use 2.0mm GootWick, which is fantastic stuff (thanks to Louis Rossmann for the recommendation). Preheating the board with hot air works wonders. Speaking of hot air - for SMD parts - be liberal with flux and don't just keep the hot air on the part - you want to move it around the part, on the legs and keep a little pressue on it with some tweezers - don't force the part to move, it'll loosen when the temperature is jsut right.
You want to save basically everything bar the SCSI and Floppy connectors, ROM Socket and the 'birdseed' (SMD Resistors, Capacitors, Transistors & inductors).
Once you've saved all those parts, it's time to get scanning! 800 to 1200dpi on your scanner. As the Classic PCB is rather smaller than a sheet of A4 paper - it'll all fit without having to merge mutiple images.
There will be a more to follow...but any questions so far?