All I use to clean the carbons I do is clean them with a wet rag, then when they' re dry fletch them.
You' re right that bohning vanes don' t have the activator for a fast set up.
You should be able to get the jig set so the base of the vane contacts the shaft for it' s full length.
The only other thing I can think of is that the alcohol you' re using may be rubbing alcohol that has an oil in it.