Hi,
Hell's yea, if you provide all the schematics and parts list
I'm always down for a little tinkering.
OK,
here it is.
The BOM is here:
Partlist for 12V/12A SLA Charger
R1 1R8 (2W)
R2 1k2
R3 0R2 (5W)
R4 220R
R5 22k
R6 2k2
VR1 470R trimmer
C1 100n
D1, D2, D3, D4, D6 and D7 BY550
D5 1N4148
LED1 Red or green LED
Q1 BC557
Q2 BC547
IC1 LM338-TO3 (on heatsink)
RL1 Relay
PB1 Momentary action Push Button Mains Rated Switch
X1 4-way Screw Terminal Block
X2 2-way Screw Terminal Block
X3 2-way Screw Terminal Block
If you cannot find a relay that fits into the PCB, or if you have another 12V activated relay with mains rated contacts (SPST, SPDT or DPST would all work as well), tell me and I can change the pads into whatever measures you give me - I just found a random relay for the layout.
The PCB can be cut along the white line and mounted as a "sandwhich" C1A should be connected to C1B etc. and not with a too thin wire (mains wire would be fine), whether you cut it or not.
The BY550 diodes could be BY550-50, BY550-100 etc. and could be replaced with any other 5A diodes.
Any questions I haven't foreseen, just say so.