Mast rebuild\hardware questions
 

Hi,
I'm in the process of completely refurbishing\rebuilding my boats
masts. Looking for some thoughts on the following.

I'm replacing the wire halyard winches with 20std winches and spectra
halyards. The only winch model I could find that will fit the existing
pfd is a two speed. Are these commonly used for halyard winches?

Also the original sheave boxes on the mast were made up of two sheaves
with the wire running between them. These don't seem to exist anymore.
Can I assume that single sheave boxes will be o.k, exit angle not too
shallow to cause chafe?

I also need to replace the cheek blocks for my boom reefing. In the
larger block sizes that I require there are no models with curved bases
or adaptor plates to match the boom profile. Why is this, and any
suggestions on options. Reefing is external.

And lastly on the stripped back spars where some of the stainless
screw/bolt heads have sheared and left the shaft behind I'm intending
to extract or drill them out and epoxy the holes. Mast will be 2
packed. Do I need to do this, can I just grind them flush or would
corrosion still be a problem?

And lastly - fill no longer required rivet holes in the mast with epoxy
bog or put a rivet with zinc chromate in these holes?

Thanks in advance

Mast rebuild\hardware questions
 

I can answer some, but not all, of your questions. A 2-speed winch is
pretty common, and in fact is preferred to 1-speed. There's a lot of
sail to hoist, and most of that is pretty easy work -- perfect for the
fast speed on the winch. But you'll want to get the halyard tight at
the end of the hoisting, and that's work for the slow speed. Actually,
we use 3 steps in hoisting the mainsail on our 50-foot cutter: First,
we simply haul on the halyard. This gets the sail to about the upper
spreader, when its weight more or less balances one of us. Then, the
high speed for the last 10 feet or so, and finally the slow speed to
put some tension on the halyard. Note that the halyard will 'creep',
i.e., stretch a few inches and then stop stretching. This is due to
straightening of the fibers in the halyard, not to stretch og the
fibers themselves, which is miniscule.

I assume you mean the exit blocks low on the mast. You might be able
to get away with no blocks at all, as we do. But be very careful to
check the lead through the exit slot to be sure there's no chafe. I'm
pretty sure you can still locate exit blocks with double blocks, though
I'm not sure where.

Boom reefing. Have you looked at cheek blocks with brackets that
run fore-and-aft? That solves the spar curvature problem, but might
not work in your case. Other than that, lots of pople use pieces of
wood, cut to fit, or filled epoxy molded in place (with wax applied
liberally in advnce, so the block isn't permanently attached to the
boom or to the cheek block).

No idea about your SS screws.

Of course you can fill unused holes with filled epoxy -- or just leave
them; that's what we do.

Rob

Mast rebuild\hardware questions
 

On 7 Dec 2005 17:58:37 -0800, "Matt"
wrote:

I'm replacing the wire halyard winches with 20std winches and spectra
halyards. The only winch model I could find that will fit the existing
pfd is a two speed. Are these commonly used for halyard winches?

Yes, usually on boats that have the halyards led aft to near the
companionway hatch (via turning blocks, line stoppers, etc).
By using line stoppers you can reuse the same winches for reef lines,
outhaul, cunningham, etc.

Also the original sheave boxes on the mast were made up of two sheaves
with the wire running between them. These don't seem to exist anymore.
Can I assume that single sheave boxes will be o.k, exit angle not too
shallow to cause chafe?

If you go single sheave it will need to be very large, at least as
large as the mast fore and aft dimension. You can eliminate the need
for double/oversized sheaves by going to internal halyards which I
recommend for other reasons. Otherwise you can get double sheave exit
boxes custom built at ang good rigging shop. I recomend consulting
with an experienced rigger in any case. A good rigger will have
solutions to problems that you didn't even know existed.

I also need to replace the cheek blocks for my boom reefing. In the
larger block sizes that I require there are no models with curved bases
or adaptor plates to match the boom profile. Why is this, and any
suggestions on options. Reefing is external.

You can use some small pieces of teak to create fairing bocks, or if
you can find cheek blocks with mounting holes on centerline, it may
not be necessary to do anything. Most larger boats have a boom
section that is flat, or nearly so, on the sides.

And lastly on the stripped back spars where some of the stainless
screw/bolt heads have sheared and left the shaft behind I'm intending
to extract or drill them out and epoxy the holes. Mast will be 2
packed. Do I need to do this, can I just grind them flush or would
corrosion still be a problem?

There are several ways to do that. Grinding flush is one option as
you mentioned. Drilling out SS hardware is problematic because of
potential for drill wander. You might be able to punch them through
with a center punch and big hammer, especially if the threads are
corroded.

Filling with thickened epoxy and sanding smooth will work, as will
tapping to a larger size and instaling a "decorative" machine screw.


And lastly - fill no longer required rivet holes in the mast with epoxy
bog or put a rivet with zinc chromate in these holes?


See above.

Thanks in advance