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LlamaHouse Ltd.
10-23-2008, 05:50 PM
Hello all,

This is my first post here, so please forgive me if I commit any breaches in etiquette. I am a relative neophyte in the wooden boat arena as well. I am currently rebuilding a 30' wooden cutter built originally by Daschell-Carter of Benton Harbor, MI, Circa 1935. I have already replaced the: stern post, rudder, deadwood, stern knee, part of the keel, and half-a-dozen floors and frames. Work is progressing well, and I was planning to strip the mast this winter (it was painted white) when I found that carpenter ants had taken up residence. Of all the pieces of wood in my shop they decided to climb halfway up the side of the building to eat the most expensive piece!! :eek:

The ants have since been eliminated with extreme prejudice, but the damage may have been done. There are two ant holes in the mast, and God-knows what damage inside.

Should I waste my time trying to bore the holes wider, scope them and try to repair the local damage, or is the general consensus that it is firewood?

Secondly, is there any practical way to deconstruct the mast? It is a glued boxbeam. I assume (maybe erroneously) that due to it's age it is glued with resourcinol, but I haven't stripped the paint away from a seam to look for purple.

Thoughts anyone?

Dan McCosh
10-23-2008, 06:47 PM
Carpenter ants don't usually attack good wood--they seem to prefer something rotton. This could mean your mast is pretty good, or pretty bad. A simple box-section mast can be dismantled, even if it means sawing it apart. Masts that old often are glued with non-waterproof glues, although that is also just a guess. A repair of a section, even a fairly large one, is quite feasible. Long scarfs can be used to replace almost any length. I would strip the paint off, and then look again--sound for rot, etc.

LlamaHouse Ltd.
10-23-2008, 07:10 PM
Thanks Dan,

Hmm...Maybe the ants are smarter than I am. I'll definitely strip it before deciding. As for dissasembly, maybe I'll try running a ultra-thin kerf circular saw blade down the seams of one side with a batten guide. The reinforcement blocks could be a problem though, I assume they're glued to the sides....maybe pry up an edge after cutting and aim a wallpaper steamer inside to loosen the glue? Ahh, the wonderful head-scratching that wooden boat work generates!!

MiddleAgesMan
10-23-2008, 07:29 PM
I don't know what sort of adhesives were used for wooden box masts back in 1935 but it just might be old fashioned hide glue. Except in the custom musical instrument business hide glue is rarely seen now'days but luthiers know how to work with it and if that's what you have you should be able to disassemble the mast, repair any damage, then put it back together with either epoxy or resorcinol. Cutting it apart even with a thin kerf blade is pretty drastic, IMO, and would change the whole picture, not to mention the difficulty involved in making straight and true cuts through the joints.

Heat will soften most adhesives including hide glue. I don't recall the proper temperature but it's higher than both epoxy and regular white or yellow wood glues. If you can't get the joints opened with a judicious application of heat I would suggest repairing any visible damage and hope for the best.

Or replace it.

LlamaHouse Ltd.
10-23-2008, 07:47 PM
I'll do a little research on hide glue and see what I find. I suspect it would be difficult to only remove one side by heating, and I'm a little afraid of weakening the remaining joints. I'll definately look into it though..Thx

sandingblock
10-23-2008, 08:14 PM
Having recently scarfed a new butt onto an existing mast, and done other repairs, I'm of the opinion that if there is a significant amount of work to be done then it is probably easier to build a new mast.

This is in relation to box section masts which are simple to make.

So if I were you I would take paint off the mast until you can make an accurate assessment of the condition of the wood and glue. Then you'll have to make a judgment call.

Just remember that if you have to do a lot of work involving re gluing and scarfing you'll need a spar bench of some kind. With all that work it's not much more to build one from scratch.

MiddleAgesMan
10-23-2008, 09:37 PM
Luthiers take wood instruments apart with heat blankets or blocks. You can buy electric blankets that will do the job or you can get a good flat chunk of metal, heat it in an oven or a fire, then set in in place where you plan to start opening the joint. The difference in wood thickness between guitars and masts will have to be addressed, however. The heat transfers through thin guitar parts without too much problem. You might have to add an insulating blanket to keep the heat in--and leave it place a lot longer--to give the heat the time it needs to get to the joint through thicker wood. With a blanket or metal block you don't have to worry about weakening other joints. The heat will have enough trouble affecting the closest joint--the one you want to start with. It will have no effect on the other joints further away. The localized heat is quite different from putting the whole mast in a steam box or oven.

If you're going for a museum quality restoration such a tedious repair might be feasible. If you just want a serviceable mast try a repair from the outside, with a little reinforcement if you think it's needed.

Or replace it.

LlamaHouse Ltd.
10-28-2008, 08:49 AM
Ok folks, I think I have a plan of attack based on all your info: strip the mast, bore out the two ant holes and scope them, attempt a local repair if the damage is not too great, or build a new mast if it is. I'm actually very interested in building a new one, but it will put off my launch plans for another season. Hopefully I can successfully repair it for now.

Thanks for all the info,

Joe

Jay Greer
10-28-2008, 11:06 AM
Since it can take a long time for real damage to be done by wood eating insects, my approach in the past has been to fumigate a suspect boat or mast and watch for any adverse wood conditions that may indicate the need for more drastic treatment.
Jay