Have run out of bagging tape - just a foot too short! Sprayed GC50 on Saturday, if the tape arrives on Tuesday - will the epoxy still bond after 4 days?

As Dravis eludes to, the longer you leave it, the less likely you will get a good bond.  Reducing the working temperature is one factor that can slow the cure and buy you more time.  However 4 days is a long time and you may well find it is too far gone.

You could slightly pre-stretch the gum tape or cut it in half length ways to make enough tape to bridge the gap.  Obviously this is not ideal and will leave you less room for error and more vulnerable to a leak but it might be worth trying it and if you can hold a good leaktight bag then crack on while the GC50 is still bondable.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant