One helpful trick is to file the base of the rail sides (both sides) so there is more playing room in the alignment. Make the flangeway a bit tighter - then open up some with a very thin file afterwards. I used to get "automotive point files" from a tool distributor - but since they don't use points in distributors any more, those are not available. There are some fine very thin diamond coated files that come with some of the file sets. I hate to buy a set to get just one file for use - but I've sold the sets without the nice thin file at need at silent auctions and made out well enough.
-ed-
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-ed mccamey-
COSLAR RR -
http://www.coslar.us/NMRA Standards and Conformance Department
PROTO & FINE Scale Coordinator
I estimate I have about 5 pounds of coupler springs somewhere in the vicinity of my workbench.