Spruce Spar Repair

[sainted]

Folks,

I just acquired a 1981 Cheoy Lee 38 with spruce spars. Overall, the spar seems to be in pretty good shape, but there is a spot at the base of the spar where the pervious owner has squished in some epoxy. When I probe around this area, the wood is soft. The area is about 2" wide by 5" tall. The rest of the spar seems ok, at least at the base.

I imagine that I can scarf in a hunk of spruce with some thickened west system. I would taper the interface and all that. Should I replace the entire bottom of the mast (on general principals? Any other thoughts?

Thanks!

Scott

[Brion Toss]

Hello,
And oh dear. Rot is almost entirely preventable, and remarkably fast-traveling in spars, once it gets started. Plan on replacing the entire base and then some, just on the (likely) chance that spores have already migrated to adjacent areas. And be braced, once you get the mast open, to find other soft spots, further uphill.
While the mast is out, aside from an excruciatingly thorough survey, plan on seating all fasteners in epoxy.
Fair leads,
Brion Toss

[sainted]

Thanks, Brion. I'll replace the base and give everything a good coating of epoxy.

Scott

[Ian McColgin]

A few thoughts based on having dealt with rot and rot-induced breaks in quite a few spars both hollow and solid, a couple of thoughts:

Try to duplicate the original structure. If the stick is hollow except for the very butt, don't stick a solid replacement up past the partners.

I'm not really sold on compression blocks except where fastenings go right through, like the terminus of lower shrouds, but if you must have blocks, shape the top as a sort of dish with a hole in the middle to let condensing vapor drain down.

Put a drain at the top of the solid part of the butt.

To save wood in solid areas, use a "cloths pin" scarf. Like this: ===<<=== with each bevel 12:1. That takes up only 6:1 over all and gives a great scarf with bend charactoristics that will match the original. I point the apex of the male end up for looks but it makes no structural difference. I make a small flat off the pointy end of the male end to ensure a clean tight fit. That leaves a gap that can serve as a guide to drill and stick in a small dowel like a stop-water. It's not a stop-water, just a hole filler, but it looks spiffier than a glob of epoxy.

In hollow areas I do each stave at 12:1 staggering the ends of any adjacent staves that get replaced.

Wooden masts are great - so repairable.

G'luck