Jason Miller commented on an earlier post:
Hey Alan, one little piece of advice with the Shinohara’s that you may want to consider implementing before you move on? Is ensuring that there is no cork roadbed underneath the switch point blocks, I have found that when gunk (usually after track cleaning & dust) gets underneath it it can sort of bind the movement a little.
I took Jason’s advice to heart and have been preparing Tortoise throw rod slots accordingly. Since the process represents an evolution from the originally described process and is my new standard procedure a diagram is in order.
The process yields slots that are all but invisible from above while at the same time removing any possible contact between the switch throw bar and cork roadbed even with gunk buildup underneath. There is a tiny gap on the opposite end of a fully thrown throw bar exposing the 45 degree trimmed cork but it is so minimal. Nothing a drop of ballast colored paint won’t hide completely. End result: free moving switch points with no gunk accumulation worries. Thanks Jas!