The BFD (Big Fast Delta) got moved across the room, for reasons unrelated to the printer itself. On the way, I broke the one diagonal brace it had installed. It was always planned to have three… but I installed one, started printing things, and never went back.
Many large Deltas have diagonal braces made of aluminum. I didn’t like the look of that, so I elected to brace with non-stretch fishing line. There are many choices, I used “Berkely SpiredWire Stealth-Braid” 60 lb test. Primarily because it was on a peg at a local WalMart.
I designed “Winders” to provide even tension.
This seems to work. Wiggling the frame with no braces results in a lot of movement up top. Wiggling the frame with the lines installed results in lifting the lower corners.