One of the builders, known as George is building a LLM locally and came round to compare some sails, but I noticed his amazing jig for making bushes to fit the 30mm square tube

the bush is set on the pin and the trimmed with a really sharp knife and dishwashing liquid as lube. If it was a hard nylon bush i think a hacksaw would be just right. Then turn 90 degrees and cut the other side

so simple , so clever