It's not exactly home-made, but it is home-modified. I used a $100 Chinese Grandberg knock-off for parts and rebuilt it with longer, heavier extrusions to fit the 36" bar on my 084. I had to run them through my other mill (ie: metal milling machine) to rabbit one edge on each, but the result is very sturdy.
I bought 2 Stihl .404 ripping chains. Seems to leave a decent finish. I didn't use a stopwatch, but it cuts a 10' length in Red Oak and Maple in about 5 minutes.
I hit a couple of hidden nails in the centre of one log. Surprisingly little damage to the chain, just a little kick that made me think "what was that?" It didn't even slow down for the rest of the cut. But I decided to switch to a carbide cross-cut chain for the next cut. Not gonna do that again! Terrible finish and very slow. I'll save the carbide chain for cutting off the stumps near ground level in the future.
The problem with this thing is that everyone else wants to try it out too!
After reading what others have done, I think future mods may include removing the rollers in place of the skids and a winch. Removing the bucking spikes and switching to the one-bolt method of mounting to the bar would not only maximize length, but also make it a lot easier to change chains. Does anyone know if the Stihl 3-foot sprocket nose bar is a suitable candidate for drilling the centre of the sprocket?
In the interests of full disclosure, this is not my first foray into chainsaw milling. My first attempt was 18 or 20 years ago, freehand, with my only saw at the time: a 16" bar on an 025 with a chain modified in what I thought was a suitable imitation of a ripping chain. I knew nothing about grind angles, I just ground the tops off alternating pairs of teeth.
The results were not pretty. No photos exist.
However, after much clean up with the bandsaw, jointer and planer and lathe, I turned that beech and oak into a staircase. And many, many bags of sawdust!