Split in an old pine mast?

Seagreen

Seagreen

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Now that I have scraped all the old varnish off my solid pine mast (pitch/columbian/sitka - dunno but smells lovely when scraped) I've noticed it has an old natural split down the grain where it had dried out over the years. This split runs between two knots and is about 6' long and possibly up to 1" deep and about 1/4" wide. A PO has tried to nullify this by pinning the split every 6" with brass pins and filling the crack with some weird varnish/sawdust combo which has now dried out and fallen out.

However, since its now up to me, should I try and fill the gap with pine splines (pitch pine, not B&Q. The Yard has a supply knowing I'm a regular) or just fill with a flexible filler? I'm thinking splines as the mast hasn't moved in years. I'm reluctant to just leave well alone as I know rot will ensue. What does the panel think?
 
A friend repairs old masts all the time, not so sure about splits but when the joints dry out they saw the joint open and reglue.
I have made a couple of hollow wooden mast's that were epoxy glued but from what you describe I think I would clean up the gap and glue in a spline with a water proof polyurthene adhesive, but thats just my opinion.
 
Probably douglas fir. You could route and spline the shake but should one of the glue joints fail that's more likely to cause rot than leaving it open where at least the air will keep it nice and dry. If you want to stop it up with something I'd go for something thick and tar like though to be honest I'd leave it be and just be sure to work the varnish in well when recoating the spar.
 
john_morris_uk said:
As a connected issue, the last time I glued a wooden mast back together, I was advised NOT to use epoxy, but Cascophen, as epoxy is too brittle for mast applications.
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People often talk of 'epoxy' as if it's just one substance with precise characteristics, whereas 'epoxy' only refers to the type of bond formed between resin and hardener, and has become an umbrella term for numerous glues of different formulations (all having epoxide bonds).

The resin used in one epoxy glue can have very different characteristics to another, and it is true that some epoxy is as brittle as glass, whereas some remain relatively flexible.

I'm a bit loath to actually recommend using an epoxy glue/filler to repair a mast, but if the OP should decide to go down this route, then General Purpose Epoxy Resin from http://www.resin-supplies.co.uk is what I would use - it remains semi-flexible even when fully cured, and I've never had a problem with it over many years and a whole variety of different jobs.
 
I've certainly heard the advice not to try to stop up mast shakes, as it's liable to trap water and cause rot. Although I presume a good job of laying in a well-fitting new piece would be ok.

Pete
 
Funny ol' life ... I've got some excess beeswax and wondered if and how it might be used on wooden boats (thinking that maybe a turpentine/beeswax mix might be good for proofing wood, rather than varnish ?), and lo and behold I came across this site: http://svrowan.wordpress.com/
where - guess what - beeswax is being used to seal their mast shakes.

Talk about live and learn.
 
Yes, I liked the beeswax option, but I've used an exterior builders' caulk to great effect on the boom with no ill effects and I was wondering if it would work as well on the mast. I'm inclining towards putting in splines with cascophen, at the moment.
 
Working boat people lived with shakes. Since a shake runs with the grain it has little effect on the mast strength. I would have thought that by cutting across the grain to insert a graving piece, you would be damaging the integrity of the mast, far more than the shake. Like the idea of the beeswax, but I really think I would thicken epoxy with pitch pine sanding dust and varnish over. Strength is not an issue, but it's a cosmetic issue (Puts head down below the parapet)
 
I'd be tempted to use West's G-flex epoxy and use a heat gun to let it run deep into the gap, following up with a sawdust/G-flex paste.

G-flex epoxy does what it sez on the tin...........
 
Seagreen said:
Yes, I liked the beeswax option, but I've used an exterior builders' caulk to great effect on the boom with no ill effects and I was wondering if it would work as well on the mast. I'm inclining towards putting in splines with cascophen, at the moment.
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Beeswax mixed with pine tar (Stockholm Tar) has been used to stop leaks below and above the waterline in wooden boats for years. It's called ettan in Sweden.

I would think that beeswax will melt in the sun? making it unsuitable in the mast.
 
Well RobbieW, its great once you are sailing, but the maintenance can get a bit frustrating, especially when the weather is consistently bad.
I've decided to go with my builders' caulk sealant. Its worked on the boom, and all I need is something brown and flexible to keep the water out and make a base for the varnish. Everything on and in the mast has to be both waterproof and flexible, so I don't think G-Flex is flexible enough.
 
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