Many thanks for all of the advice, it has been a great help.
Your welcome and please pay us back by helping another newbie in the future.
I think widening the boat to F16 is the most logical. Can I use my old mast section to replace front beam?
Yes. You'll have to get a new dolphinstriker strap and a new rearbeam but all other fittings and parts can be re-used.
Am I crazy to look at using a second hand A class carbon mast as a replacement wing?
Only if you can't find a mainsail to match. You can only sail solo then as the A-cat mast will not withstand double trapezing. In the way of drive and balance you should not have to many issues. At least no issues that you can't solve be raking your mast backward or forward. The A-cat boom will be to short however, so you'll need to fix something up here as well. Not a biggy, however.
Am I crazy to look at ex carbon masts as replacement for front beam and glue rather than bolt?
These will be too small to fit properly in the beam landings and I'm not to confident that teh mast section will like this new role much. Darryll, you're more experienced in carbon mast layup then I, What do you think ?
I notice some 18s are doing this for a more rigid platform.
What 18 's
Wouter