Background follows:

To see an example of a type of press I'm considering, please see this:
https://www.dog.itshisworld.com/gpage1.html

For my press I had intended to place the hydraulic cylinder beneath the compression chamber- eliminating the chance of contamination. Everything else will be hardwood- or possibly (fir, pine) depending on size.

I would like to 'rest' the hydraulic jack on two pieces of angle iron that are then braced with 2x6 or 2x8. They form the floor of the wine press, and might possibly have a small 'filler' board to keep them from shifting. I expect to use several carriage bolts to hold this angle-iron reinforced structure together. I have access to a OxyAcetylene setup but had not intended to use it for this design.

This floor beam would transfer the force to a pair (4x) of vertical beams on either side. A small filler and stop would separate the two vertical beams. As before, a carriage bolt or two would be used to keep the beams in alignment with each other. These could be made out of laminated plywood (3 to 4" thick) or 4" post beams.

The top of the press would have either one, two, or three 2x8 or 2x12's to transfer the force to the follower. Square stock (spaced with holes- I can't recall what it's called) would be set with a pin to allow me to drop the press further and further down as the pomace was drained of juice.

I was thinking of making the follower (the piece that covers the pomace/must) from simple 2x3/4 plywood and a steel cup to help distribute the force.

That's the background. My concerns are bracing the 20 ton jack properly and preventing the entire press from disintegrating. I do not expect to exceed 6 tons of force with this design as that would exceed 100 PSI on the pomace, and I'm told bad things begin to happen to grape seeds around there.

Given that the pot is 12" in diameter and I'd like to upgrade to at least 18" in the future, that requires a minimum floor beam length of 30" + vertical beam thickness, or about 40" total.

How does one go about calculating the yield strength of angle iron in this case- am I over engineering the bottom? Are my concerns justified?

I have been using this as a source of information:
https://www.auf.asn.au/scratchbuilder/wood_strength_values.html

I'm afraid to admit it but I'm a ChemEng/Chem, although it's been so long since I took my materials courses that I don't even know where to begin.

Thanks in advance for any insights you may have-