After successfully splicing 1/2 inch line as a learning exercise, I bought some 3/8th inch line for a spinnaker halyard. I bought extra in case I screwed up the splice, but 3 tries later, I still couldn't get the core back into the cover. I can't see photos of your coat hanger tool here at work, but I'm going to check it out when I get home.
S/V Old Shoes
1973 Pearson 30 #255