Great project you got going. Thanks for taking the time to document your progress. I've built 2 stands using the same structural design as you. Let me tell, when I read how you made the cuts in the 4x4s all at once, I was like "doh!" I did them all one at a time.... oh well, measure twice, cut once, right?
If you're worried about being able to slide out the sump, you could frame up a side door on the stand & slide it out that way. With proper framing and reinforcement on that side, you shouldn't lose structural support.
As for repairing the chips in the glass, have you looked in to using one of those windshield repair kits that they sell at auto parts stores? I haven't tried in an aquarium, but the (small) repair on my windshield is nearly invisible. I believe it's an epoxy, but I haven't looked into it's "aquarium safeness".
GL with your project & keep us updated!
If you're worried about being able to slide out the sump, you could frame up a side door on the stand & slide it out that way. With proper framing and reinforcement on that side, you shouldn't lose structural support.
As for repairing the chips in the glass, have you looked in to using one of those windshield repair kits that they sell at auto parts stores? I haven't tried in an aquarium, but the (small) repair on my windshield is nearly invisible. I believe it's an epoxy, but I haven't looked into it's "aquarium safeness".
GL with your project & keep us updated!