Building on the idea of the PVC, you can always get someone with a 3D printer to print some rings that match up to the inside diameter and length of the different sets.
That would be cheap and exact.
Just don't get @Boarderguy measurements.. his 6 inches has always seems a bit short for some reason
That would be cheap and exact.
Just don't get @Boarderguy measurements.. his 6 inches has always seems a bit short for some reason