Originally Posted by
wizard
Interesting concept that I kinda like. However I have a concern or two.
1. I really don’t see 3” being thick enough. You will want to reinforce the concrete with rebar or wire mesh or both. And frankly I think 3” is a little thin for that.
2. The other thickness problem is that you will likely want to cast in place mounting hardware that is well embedded in the concrete. In some cases you will need solid concrete support around those inserts. The inserts could be J bolts or bars to tapped holes either way you need thickness to assure security. While you might be able to use threaded inserts or anchor bolts after the concrete has hardened it might not be the best solution for every mounting need. Locating and drinking precision holes in concrete will be a huge challenge.
3. I really don’t see the point in leveling and grinding if you are Going to epoxy level. If you are going to grind why not do it with the precision needed for your rails. My understanding is that companies do grind concrete to particularly nice flatness so that is always a possibility. Terrazzo floors for example can be ground rather flat. (They have to be otherwise you would see the defects in the polished surface). The big advantage though is that your rail system gets bolted directly to the hard aggregate filler.
4. By the way I’m not too certain grinding in the green state makes sense, I’d wait a good three months for the concrete to harden and stabilize.
5. Your wood base needs refinement to avoid collapse under weight. At the very least add some X bracing or other structural improvements. By the time you are done that table will weigh in at several hundred pounds, it’s rolling over onto somebodies feet will be painful. In fact the top heavy nature of the table is a real concern.
6. While it might not be a concern at the moment moving the table will one day become an issue. The lower runners connecting the legs do not look like the could handle a pallet jack under them, raising the table to move. When your build is finalized and comes close to a ton (maybe far more) you need to think about how you will handle it.