Just finished up making the first loop "permanent".
Found a smaller diameter pipe to interface with the heat block and I wired in the devices in their final positions. I ended up going with oversized linear 5V regulator modules for the monitoring panel at the front:
This whole section runs off of its 12V supply and their is a single little relay available to patch through some logic to the final external power supply. Depending on the control configuration of the supplies (for the peltiers), I may need some more relays for interfacing.
There is also now a 4-switched power-board that I intend to run:
-->Loop 1 @ 12V
-->Loop 2 @ 12V
-->Cooling fans @ 12V (just for low power loads, serious stuff pipes to external heat dissipation or buffering)
-->Main 1kW power source (with logic interface for on/off I hope).
On the way in the mail are:
Slowly but surely getting there. I'm also concerned about the galvanic corrosion between the copper (which everything is made of) and the heat blocks (only available in aluminium at that size). However, the copper is almost all coated and and permanent installation that has time to start significant corrosion I'd be able to use an anti-corrosive coolant I imagine. Still, I'll try to make sure the aluminium blocks are "removable" just in case and won't trap them in place.