Thanks Hogleg!
No Patron, no rods. Back in the olden days, we would stack the blocks in a special glass block mortar (more adhesives), there were twist-off spacers that would help with stacking but the mortar was a mess and it was a PIA to keep it all plumb and level. Your choices for color was white or white. Strong in the end but it was never a question of "if" you would get mold but, "when". I have tried many times to drill little holes in the mortar and with a syringe, inject bleach to get rid of the orange and green mold visible thru the blocks themselves. I hated the old style of installing glass blocks.
Nowadays we use a "stack and grout" method. They (Seattle Glass Block) will build modular segments in any configuration, round, stepped etc. and using a plastic strip, they get glued together with 100% Silicone. On site we stack the pre-made modules, running thick beads of Silicone between each lift glueing it all together. Once the wall is built, it is wiggly but that's only because the silicone allows a 25% joint movement. It gets grouted with standard sanded grout in whatever color you choose and like a basic brick wall, it is solid.
From SGB website "stack and grout".
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On the palette at our job site, each lift was a pre-made row of two blocks. You can see the top row missing the last piece of glass cap to be cut to fit tight to the wall, and glued on after assembly.
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Bet pic I have of the grout.
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