Last weekend I was able to have a go with my friend Rich's Logosol Big Mill / TimberJig chainsaw mill:
The basis of the TimberJig is an attachment for a chainsaw that lets it run along the aluminium bar or a square corner of wood:
Rich had built a log ladder, and on top of that had a couple of Logosol log-lock clamps. These can be set up with the jaws close together for a round log:
Or further apart if you're putting the flat face of a partly-milled log on them:
Once a log is lifted in..
... you just push the jaws firmly onto the log, and then lock the clamps in place.
The aluminium bar is fixed to a pair of adjustable brackets, which are used to change the height at which the chainsaw is cutting. They can be screwed to the end of the log itself if you're out in the woods, but Rich had mounted them onto the log ladder. He'd also added some spacers, made of sections of copper pipe:
These ensure the saw chain doesn't hit the log locks!
Rich thought I ought to have a 'trainee' badge as it was my fist go...
It's actually very easy to use, you just open the throttle and walk slowly along pushing the saw, making sure to keep it firmly placed on the aluminium bar.
Here's a couple of close-ups of the milling I took when Rich did some:
The only downside is that I gather you end up having to sharpen a lot of chains!