Hi W,
In my hayday, engine turning was one of the things I used to do on most of my engines, especially on the dozens of finger engines I made for friends and relatives.
I used to use cratex rubberized bobs, from about 10mm to 25 mm diameter, wearing away on a strip of emery to get to the exact size required for the pattern and after working out the length of lines plus widths I usually work to a 1/2 D forwards by 1/2D sidewards and knock the cratex bobs down to the diameter needed and starting in the exact centre of the shortest edge of the plate.
Many a time it was for more than just one.
I can commiserate with your getting fed up of cutting the pattern, these three took four hours each plus one bob for each piece, but if you want it to look good, taking your time is an absolute must.
These two pictures show the same plate with the light shining at different angles, it is for this reason that engine turning looks so good, it is like having liquid surfaces.
If you want to see engine turning at it's very best, have a real good look around Eamonn Keogh's site, he is very approachable and he gave me many tips on how to do it a long time ago.
http://www.cs.ucr.edu/~eamonn/et/et.htm
Hope this helps
John
