I'll watch the video when I get time but would like to give you some advice that wood makes an excellent heat source. Well to me it does anyway. Good luck with the bench and remember cut twice and measure once.
Wood will work just fine. Don’t know exactly what you have in mind but if you are going to have long spans of unsupported boards split them and then glue back together. Really stiffens up the wood and there will be little to no warping.
TiteBond 3 and a Kreg Jig, your good to go… The Kreg Jig is available at the box stores and minus the special screws, makes things easy to build and strong…
Use somethin’ bigger than 2x4’s where you can. 6x6’s, 4x4’s and 2x6’s etc. Lathes be freakin’ heavy. And vibratey. And vibration and flex in your table is NOT a good thing.
subscribed to a interesting project…
I would do what you can to get a steel table. Big Chuck at the machine shop says you can find them used , cheap , and already made
This kind of machinery needs a solid foundation. I don't think wood is a wise choice.
I'm sure there's someone who can help fabricate a decent metal frame for it.
Don’t underestimate the strength and durability of wood. Properly braced, glued, and nailed or screwed wood is hard to beat.
This table was built 27 or 28 years ago. 2x4 bracing, 4x4 legs, and 2 layers of 1/2 inch plywood for the top. Built to mount a 4 stage reloading press on. Just as flat and square as the day it was built.
Next two tables were built around 18 years ago. 1x6 decking boards for bracing, 4x4 legs, and butcher block tops. Both are also as flat and square as the day they were built.
You don’t need to use a butcher block top, plywood will work fine. I would put a cross brace under the top running the shortest distance every 12 to 16 inches for rigidity. Using 4x4’s for legs lets you have a full 3.5 inches to screw to on both the sides and ends. I would use glue as well as screws and clamp tightly when assembling. All three tables also have bracing about a foot off the floor with a piece of plywood mounted on them to form a shelf. I would not hesitate to place a full size car or truck on any of these tables. A lathe is nothing for either of these table.
A sturdy wood table is very capable to hold that lathe.
I had my first Milling Machine on a wood table,(A 1961 stand-less Knee-Mill) the machine weighted over 500 Lbs. The legs were 4x4”s, the frame was 2x6”, and top was 2x8”s. Looking forward to watching you work your magic on the new lathe with the MagLites and anything you build. 
Metal ain't cheap around Tyler. The fab shop that I could find here, quoted $350 to make one and this one will end up being quite a bit less. Many hobbyists have used wood tables for these same lathe's and they work just fine. Have faith.
My gunsmith buddy worked on a table of his own make that was all wood. He bored holes through 2x4’s on edge and ran 1” all thread through the stack, glued em and bolted em together then cut off the all thread ends flush on the outside and glued on a last 2x4, screwed it on as a cover.
With 4x4 legs and a plywood shelf at the right height off the floor, the thing is virtually indestructible.
The size you’re talking about here should make it easy to make an extremely solid bench.
Good luck OL... looking forward to seeing this taking shape!
07/25/15 09:30AM. Updated the OP.
If you build it, and you find that it needs stiffening up, 5/8”* plywood connecting the legs at the back and sides will do wonders. (They could even be 2’ wide and still help massively, if you wanted to maximize the yield from a single sheet.)
Oh, and if the top needs stiffening, a layer of plywood underneath the top would create a crazy stiff torsion box.
- * ’course, it’ll be labeled 19/32”, just to confuse us home despot shoppers…
Wood is good! It dampens vibration. I have a wood bench my Dad made me 35 + years ago, still in use. I suspect that if Justin builds it, you could park a tank on it with confidence. 
Dan.
Regarding vibration , what about a rubber mat on top of the table,
so justin doesn’t wake up the neighbors at 4am.
I like wood. Gussets(glued and screwed)are a good idea for stiffening the angle between legs and top on a lighter weight table, as well as adding a shelf below. If the shelf below is too low you can attach cleats under the top for a debris tray. Wood is also compressible though so oversized bolt washers should be added under the correct sized ones.
Wow a hand saw—I couldn’t imagine cutting all that with a handsaw—I’m a carpenter in fact—as far as two lines —if you’re right handed you cut on the right of the line —two lines seems like it would make you cross eyed LOL—I sure could of sent you a skillsaw (circular) I only have around 15 not in use (retired framing/trim contractor) I have woodworking tools—If your table isn’t quite solid enough try boxing 3 sides with plywood or at least put something like a 2x12 tight in between the legs
Can’t wait to see what cool stuff Old Lumens makes !!
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