in mast reefing.- is it a problem

[ashtead]

I suspect this might depend on condition of system ?

 

[Baggywrinkle]

With modern in mast furling systems, can the sail area be increased/decreased at any point of sail, without modifying course/wind angle? Can one adjust the surface while keeping a steady course sailing with the wind from say 120-150° (polar)?

Pretty much if it has no vertical battens. You don't want the sail against the spreaders when you reef, so pulling the boom in as if starting a gybe and then easing a bit on the outhaul, then pulling in on the furler, you can take it in say 50cm increments while maintaining course.

 

[ashtead]

Don’t they all have vertical battens nowadays ? I’m sure the ones offered on Moody (ie from Hanse empire) did but we didn’t opt for them so not sure . Maybe Hanse owners know though?

 

[NormanS]

Don’t they all have vertical battens nowadays ? I’m sure the ones offered on Moody (ie from Hanse empire) did but we didn’t opt for them so not sure . Maybe Hanse owners know though?

The advantage of vertical battens is that they allow some roach. Mine has no battens, but I'm quite happy to accept the potential reduction in sail area.

 

[Baggywrinkle]

Don’t they all have vertical battens nowadays ? I’m sure the ones offered on Moody (ie from Hanse empire) did but we didn’t opt for them so not sure . Maybe Hanse owners know though?

Vertical battens are both a benefit and a disadvantage.

The main furls better without them as when the sail is under load they add resistance while going into the mast slot - the further off the wind the course, the worse it is as the battens have to be pulled across the edge of the slot before going into the mast and the batten pockets + battens are thicker than the sail.

They do however give a bigger sail area (more roach) and a better sail shape.

I moved from no battens to vertical battens and have noticed that it is better to head into the wind if I want to furl more than one batten spacing.

 

[Concerto]

My experience of a mast furler was on my parent's Moody Eclipse 43. We never had any problems with it in 4 years of ownership.

By comparison, I was alongside a boat of about 30ft some years ago that had a retro fit furler. When he bought a new mainsail he went with a slightly heavier cloth for better sail set. However the sail was now slightly bulkier and he could no longer completely furl it away leaving the last couple of feet always exposed.