Been a while.
I've finally finished off my A4000 Rev B with full ceramic capacitors using a polyimide heater and a 450W PC PSU.
Polyimide heater won't be cheap, I bought 3 different ones as a lot for a total of $650 USD but I think because they now have the artwork for the heater you would be able to get them for far less.
The copper plate is 3mm thick 35cm x 25cm with the heater stuck to the bottom using the provided adhesive (it's already on the heater when its shipped) and you just have to make sure it's flat and there's no bubbles in the heater.
When you first turn the heater on it draws around 12 amps of current before settling down to around 10 when it gets up to temperature. My first experiments with the heater in open air could only yield around 80 degrees C, but by putting it into the pine frame and putting a layer of alfoil beneath it I was able to get it to 120 degrees.
The wooden surround is good because it gives you somewhere to rest your arm when you are soldering the capacitors in place. You must ensure that you have cleaned up the pads as well as possible or you will have a hell of a time trying to solder the new caps down keeping in mind that your hand is hovering above a board at 120 degrees C!
The small screws holding the stand offs in place under the copper plate won't cause an issue with the board because the component legs / SMD parts keep it above them anyway.
The heater takes about 40 minutes to come up to temperature and it doesn't cause any of the plastic to melt so you don't have to remove anything before you start which is nice.
C181 is made using two 47uF capacitors stacked on top of one another
I'm going finish my A3640 in the same way along with one more A4000 board and then nothing else. If you have any questions feel free to ask via the usual email.
zero242@internode.on.net