As I remember, the tie cutting was usually done in the winter and the snow would help stabilize the logs. I don't recall any other devices, although the tie hacks might have improvised something if a log tended to roll. The bark was probably removed in the woods, although this would be tough to do in the winter.
On the Sumpter Valley we have quite a number of hand hewn ties, all relay stuff, and some of them are considerably larger than eight inches. A few must be close to 16 inches on the butt end. These can be heavy, but not as bad as Oak ties.