Its probably a given that metal is better for a lathe stand, especially when getting into around a 10' and larger - but... you do what you can with whatcha got!
I built this stand about 4 yrs ago for delivery of my new Birmingham 12x36, it was derived from some unknown apparatus won by my friend at an Air Force base auction - stainless steel tanks, loads of wiring/electrics, probably cost us taxpayers a gazillion dollars. Any way, after my buddy stripped the stainless and most of the electrics off, he gave me the frame. After doing some cutting/trimming/shortening, etc, I ended up with this, except for adding 3 pieces of 2x2x3/8" angle welded in to fit the lathes mounting bolts.
I added a piece of 3/4" plywood on top to make a table top area - it doesnt perform any support function - got the lathe mounted, painted it and moved it into its new spot
Built the cabinet/drawer modules - the far left is for short specific cut-offs, brass aluminum, cast iron, etc, the middle is for chucks, etc, and the drawers speak for themselves...
This is it today with my South Bend and with many more 'extras' gathered around for convience