OK I finally got pictures taken of the progress. Some of the pictures were taken about a week ago, but the latest ones (easy to tell which) were taken just today. But after about a week of shoveling dirt, rock and sand, as well as raking it all out fairly level I was finally able to get going on building the greenhouse structure.
First to elaborate on the lids for the
nutrient reservoirs. The small twist off top wasn't going to be adequate for maintenance. So I simply cut a larger opening with my trusty rotary tool. I created a flexible lip using vinyl baseboard. Though I forget what the actually call it, but it is the vinyl baseboard typically used in commercial buildings. It comes in either 4 foot pieces or rolls of 20 feet. It is 4 inches wide so I cut into two 2 inch wide strips. Then just bolted it to the reservoir to create a one inch lip all the way around. Then I added two 1x1 composite decking pieces for added support. I still have some handles to add to it, but haven't gotten around to that yet.
There are 12 tubes coming out of the ground. That is 2-1/2 inch electrical conduit. I cut 6 of them out of each 10 foot long tube. Their 19 inches long each, and 10 inches deep in the ground. I used a small level to make sure they are plum vertically, and a string line to make sure they are lined up correctly. They are spaced 4 feet apart on center on the long side, and 10 feet apart on the short side.
The 2 inch electrical tubing will slide snugly right down into the 2-1/2 inch tubing in the ground. They will then be bolted together. Then a baseboard will go all the way around the greenhouse, and that will be attached to the electrical conduit with 3 inch decking screws. I got a real good deal on the wood for the baseboard today. I was going to use something else, but Home Depot had plenty of 2x6 pressure treated wood in there "cull" bin. And at $0.51 cents for each 4 foot length piece, I'm now able to do the entire baseboard around the greenhouse in 2x6 pressure treated wood for less than $15 total. The 8 foot 2x6 pressure treated wood goes for $8.97, and the 10 foot goes for $10.97. I literally saved over $50 by luck.
The two poles sticking up are about 1 foot taller than their going to be I think, so they will likely be a little shorter. Leaning up ageist the retaining wall is the upper "A" frame that will go on top of the vertical poles. If my calculations are correct, the greenhouse will wind up being about 13-1/2 to 14 feet tall at the top apex. I don't have a later that tall that I will need to attach the horizontal framing with, as well as the 6 mil plastic covering. So I will build a ladder/platform out of some of the other "cull" wood (I don't know why they call it that) to be able to reach it.
As for the box frame around the in-ground reservoirs, most of that was made from the "cull" wood I bought a couple weeks ago. But at that time they only had 2x4 pieces of the pressure treated wood. I had to cut 2 of the 2x4's I bought for the greenhouse framing to finish making all 3 boxes. I built them above ground (I forgot to take a picture of that), then just used a large rubber mallet to pound the 4 stakes (in each corner) into the ground. I used a level as I was going to make sure they were straight and level. Then we just back-filled the dirt in around the boxes.