i've been sitting on this for a few years, not sure if i want to release it, but since i see more people attempting to mech these days, i thought i'd help out a bit.
https://imgur.com/4fC58YoSuper (Inside Spawn) Notes:
-Designed so that 2-3 facts have vultures spawning inside
-Walls are made with 2 supplies, 3 factories, 1 rax all placed down before 2:30, before most midbuild zealots arrive at your base
-Be careful where gas is on the left side, 2-3 assimilators can be built so zealots can pass through
-If gas is on the right side, assimilators can be built but if you build a refinery, zealots cannot pass and probe cannot build assimilator.
-Zealot can't walk through with assimilator if gas on top or bottom (12 or 6)
-12:00 the wall is very tricky this is the best wall I could come up with. The rax is placed there for force scvs to spawn to the right side. It can't be repaired, but it can be floated if it is targeted by zealots
https://imgur.com/O29NozVSuper (Outside Spawn) Notes:
-Walls were designed for all 3 factories to spawn vultures outside, which may be preferable vs midbuild zealot/cannon aggression, as vultures can snipe probes trying to make cannons while just microing vs zealots. If they attack your wall you can just repair.
-Gas positions in the photos are all tested and scvs do not walk outside wall
-tried to design walls all as spacey as possible for room for supply depots.
https://imgur.com/0OoRIsuFPM (Inside Spawn) Notes:
-at least 2 factories spawn vults inside
-first supply needs to be the one near the gas, so that it pushes SCVS to have optimtal mining.
-all walls designed to be safe against assimilator trick, zealots can't go in no matter how many assimilators toss makes
https://imgur.com/mF06GEeFPM (Outside Spawn) Notes:
-Although the simcity is meant to allow T to skip producing any marines at all, all walls are designed so that marines pop inside the wall.
-for 7:00 and 6:00, 2 factories spawn vultures on the outside
-for 5:00, the best i could come up with is only 1 factory spawns vultures on the outside
-the rest of the bases have all 3 factories spawning on the outside