Importance of cap shrouds being in column ?

[Jon Neely]

PT.2, Got the mast down today!!! quick question, lots of screw that haven't been moved in years and where not coated at all. After heating them I still am breaking off about 50% of them. Do you have a better method? For the screws that have broke do I leaved the stainless or do I attempt to drill them out?

Thanks!

Jon

[Brion Toss]

Hi again,
Ah, frozen fasteners. Heat, Kroil or P Blaster, and especially an electric impact driver are your friends here. Also cursing. Even if you get all the rest of the fasteners out intact (unlikely), you will still have at least a few stubs. If you try to remove them by drilling, you will almost certainly have the bit wander off-target and punch through the adjacent aluminum. But if you leave them there, you won't be able to put the fitting they were holding back in its original place. What then? If you move it a slight amount, you'll have holes that are too adjacent for comfort. But if you move it a lot, you could end up with fittings that are poorly placed.
So do your best to get the rest out -- for reasons we can go into if you like -- and hope that everything is already poorly placed, so you can drill fresh holes, far away, in the right place.
As for altering spreaders vs. chainplates, the continuous reinforcement of the original structure is a good thing, especially for the uppers, which take almost half the total transverse load on your boat. On the other hand, most boats don't have that setup, and do just fine, so long as the chainplates are mounted with sufficient distribution area.
Fair leads,
Brion Toss