Craig

I'd be very surprised if its a mm...thats huge. I have seen tubes when the shrinkage varies the fit, its worse on the smaller tube dia's The Rookie one used to suffer too. A light sand to key and a brushed coat oif wing skinning resin should cover it and allow you to sand to fit with a smaller dowl and some 240 grit paper. The Factory usually covers this before shipping (your wings might have been done) Sorry this one slipped through QC.
Its near impossible to mould a perfect fit...when I did my MR Lightning it took me 6 attempts to get four tubes!!

Dw