OK Bonding Day !
Simple really, drill a few holes, tap a few holes, crimp a few tubular lugs and shrink some heat shrink sleeving on, what could be easier

Well very oddly my Cembre HT45 hydraulic lug crimper (of 1985 vintage) decided that today was the day to start playing up - it was somehow hydraulically locked and would neither open nor close. After a bit of an oily session on the bench dismantling its pump mechanism and its release valve, cleaning and putting it back together normal service was resumed - I'd only used it late yesterday afternoon to do that test crimp, and it was fine then - very peculiar.
So, slight delay starting, but I've decided to bond the Furnace Body, and Chiller Unit to a common point on the roof of the Furnace driver, and from there to the steel frame of the foundry building.
The very fine strands of the 70 mm CSA welding cable that I'm using make it nice and flexible, but it's a bit of a challenge to get the strands all into a crimp lug at the same time and also manipulate the crimper. I hit on the idea of compressing them with a small Ty-Wrap right at the end of the stripped length, then pushing the crimp lug on, which pushes the Ty-Wrap back towards the un-stripped cable sheath. When sufficient is in to be stable I then cut the sacrificial Ty-Wrap off pushing the strands fully into the lug. Unconventional, but it works for me !
So everything in the actual foundry building is now bonded together with ridiculously heavy cross section cable - better bigger than smaller

Yet to do is bond the Generator, and the frames of the four buildings to each other.
I should perhaps explain:
A/ My Welding Shop is a steel framed 'lean to' added to the South side of my main workshop, and is made of bolted together RSJ's and angle iron, fitted to flying brackets welded to the steel frame of the main workshop.
B/ My Foundry is a steel framed building added onto the west end of my Welding Shop, and although again of RSJ and Angle Iron construction is fully welded but as far as I can tell is 'free standing' as far as the steelwork is concerned, and just joined by the roof so no real electrical connection between the two.
C/ The 'Stable' where my big generator sits is another 'lean to' added to the North side of the main workshop, and is made from RSJ uprights and rafters as three frames, but they are held apart by timber purlins and free standing so again no electrical connection
So bonding this lot together gets a bit complicated. Certainly I will bond the generator frame to the adjacent RSJ frame of the stable, and try and get a cable through the wall to bond them both to the steel work of the main workshop. And I will try and bond the foundry, main workshop and welding shop frames together where they all come together at a corner. But I don't think I'm going to go as far as bonding all the stable frames together - not fully decided - we'll see!