Surplus holes in mast.

[Ian G Wright]

Patience has a strong solid wooden mast. This winter/next spring I'm doing a minor re-rig which will reduce the number of eye bolts through the mast by three.
How best to plug them? A dowel to fit the hole plus a cross grain plug at each end? Dowel straight through?
Opinions please,,,,,,,,,,,

IanW.

[Bob Cleek]

I doubt it makes that much difference, but for my money, I'd take a nice piece of the same wood the mast is made out of, hopefully with about the same number of rings per inch, well dried, and turn a dowel and put that in. That should ensure that the shrinking and swelling stays about the same rate. What you don't want to do is stick something in there that is going to swell up more than the spar and split the bugger.

[Mike Field]

And I'd go with both of you -- same timber as a dowel, but with each end covered by a plug so that the end-grain isn't exposed.

[martin schulz]

...best thing is not to put any holes and eyebolts through the mast.

I just have rope or leatherprotected steel loops around the mast held in place by small wooden wedges screwed in the mast with bronze screws. Workes fine.

[Ian McColgin]

If the concern is either strength or looks, then a dowel does not appear a good solution.

Why not a conventional dutchman scarfed in place? If this is a solid spar, go ahead and dowel repair first, then make a dutchman for the outermost say 1/4 radius, where the strain really is anyway.

I doubt that strength is a problem here.

G'luck

[Scott Rosen]

I suppose you consulted a professional rigger about the changes. If so, he could tell you if the holes would create any structural problems. I'm guessing that you only need to fill the holes to keep water out and for cosmetic reasons. If that's the case, then I agree with the dowel capped with a bung. Or you could fill the holes with an epoxy filler capped by a bung.

[Ian G Wright]

Originally posted by Scott Rosen:
[QB]I suppose you consulted a professional rigger about the changesQB]Good Lord, no! Apart from Brion Toss that is, (does he count?). Look I designed the rig in the first place,,,,,,I did what I normally do; think about it for a year or twelve, look about me for what other boats do, ask for opinions here and on other trusted BB's, think about it again and try to anticipate any problems, talk about it in the pub, do a cost/benefit analisis, draw out a rough plan to check the angles, caculate loads, think some more, drink beer, get round to doing something about it,,,,,,,,
Don't you,,,,,,,,,?

IanW.

[Scott Rosen]

Since you put it that way . . .

The loads on a mast are mostly compressive loads. I would guess that the strongest fix would be a scarphed in piece, properly glued, etc. I would also guess that a properly glued dowel, even though the grain won't be running with the rest of the mast, would have sufficient strength to handle the compressive loads.

The problem is, you see, I'd just be guessing.

[Bruce Hooke]

If the holes were not a structural problem with the eye bolts in place (which they presumably weren't since the mast is still in one piece, I trust :D ) then I don't see why they should be a problem with the eye bolts removed, so we are basically dealing with cosmetics and keeping out moisture. So, I would go for a softwood dowel, with a cross-grain plug at each end to protect the end-grain of the dowel and blend in better with the mast. I would also leave a little space between the dowel and the cross-grain plugs so that as the mast shrinks and swells with moisture changes it doesn't lift the cross-grain plugs.

[Ian McColgin]

The bolt makes for a hole with no supporting structure as it is, so if it does not break with the bolt there and if there is no new strain added somewhere else that has the effect of putting a greater bending strain than already existed, it will hold up even if left as a hole.

Don't worry. Make it look nice.

[wolfietuk]

When plugging or patching semetrical patches are noticeable. a perfect circle or square will be seen. You may want to use a dowel and then cut a dimond shaped plug. Get a nice long angle against the grain. and match the grain as well as possible. Also remember that if it is over about 6 feet in the air 99.99% of people wouldnt notice an ebony plug in a spruce mast.

Rick