I /think/ what BobL means by "roll your own" is to make your own mill from scratch. I take that as his meaning from context and from the fact that I know he has made several Alaskan type (and maybe other?) mills from scratch. "Roll your own," generally, refers to rolling one's own cigarettes, which the Brits and Aussies are more prone to do than Americans. They end up using the phrase to mean any type of "make your own thing when there's a mass-produced version of that thing available but for probably a higher price." Sorry if this explanation seems patronizing - I don't mean it to me. I just thought I sensed a mis-communication happening.
If you look at several pictures of Granberg or other Alaskan mills and are fairly handy, have time, can weld, etc. then it's probably not a big deal to make something similar more cheaply from commonly available stock. And just like with cigarettes, if you know what you are doing and use quality components, there's a pretty good chance that you can make something as good or possibly quite a bit better for less money.
Again, my sincerest apologies if I have misunderstood the above situation but I lived in England for a year and found that the small differences in the way the language gets used can cause major mis-communications. For a quick example of how things can go terribly wrong, look up the subtly (but very important) difference in how Brits use the word "horny" as compared to Yanks.
