Since I've found out that turning Cocobolo will give me a nasty rash for a couple of weeks, I don't use it any more (well, unless the price it right).
It is said that there are two types of woodturners:
- Those who are allergic to Cocobolo, and
- Those who will be.
Seriously though, once you've been sensitized to Cocobolo, your reactions will only become more severe. It is primarily the shavings or dust that is the allergen, so simply handling the wood does not usually lead to a rash. If you have good dust collection, use a respirator, wear tear-away gloves, and wash your hands afterwards, you can probably prevent any after-effects. The final solution, however, is to avoid Cocobolo altogether.
Getting back to the original topic, I generally put a CA finish on Cocobolo (so that any users don't run the risk of a reaction). When I do, I wipe the wood down with CA accelerator (or acetone) on a paper towel to strip the surface oil from the wood first. Then the CA will adhere better. I do a few layers of thin and then medium. I don't use BLO anymore, but there's no reason it wouldn't work with the medium CA layers.
I hope that helps,
Eric