Rollers would seem the best way to do it. I think the only difficulty then would possibly be to make it portable. Which could definitely be done its just a question of good design.
If we were to build a narrow gauge one it could even be multi gauge. say 15inch and 2ft? I’m not sure how that would work but I’m sure a way could be found.
If you could do that Chris it would be very helpful as this is an area that I am quite interested in. I also think more knowledge on this subject will really help our projects now and in the future.
John, from what I’ve read in Wardale’s book I think you are right, but the reason that it was used was that it started to solve other issues like spark throwing. It was definitely a hindrance on the QJs in China.
I also agree with Jamie that micronized or pulverised firing is worth another look.