When I was a kid (~40 years ago) you could get spiral coping saw blades
similar to the ones now available for fret saws. They mounted in a
standard pin-mount frame by having a pair of right-angle bends on each
end. They were one piece, and were only slightly more expensive than
regualr blades. They worked very well, but I have long since used up my
supply. I did a Google search, but came up empty. The only spiral
coping saw blade I found had large loops on the ends and were pricey. I
don't think they would work on my frame.
Does anyone know where I could get such a thing anymore?