just stripped the mast: need some advice

[rebel heart]

Hey everyone! My name is Eric, and I have a Hans Christian 36 here in San Diego. We bought it a few years ago to do a "big trip" once we save up the correct amount of freedom tokens. It has a (varnished) wooden spar, and one of the spreaders was rotten. I needed to haul out for a paint job, so I also took the opportunity to pull the (deck stepped 44' spruce) mast. I knew there would be problems, as I doubted anyone else had pulled it in quite sometime. Looks like I was correct.

All the pictures, so far, are here:
http://rebelheart.squarespace.com/pictures/march-2008-haul-out/#gallery86935

We found a rotten patch, about four feet from the mast head. Not exactly what I wanted to find, but oh well.
When scraping out the rot, we found termites in the rot. We think we got them all, as we scraped until there was absolutely no trace of them, or their little holes. What worries me is that one of them could have fallen further down into the mast, and I'm none the wiser.
We found a small pocket of rot, maybe the size of a quarter, and about half an inch deep. It's right above the thru-bolt location of the intermediate shrouds. I'm thinking I can hit it with epoxy.
The scariest thing is a screwed in (non scarfed) end to end patch that someone put in. It's right near the rake bend, I have a fixed backstay, and I have no idea what's behind it. The pictures for that one are near the bottom, about 5 from the bottom. You'll note the plugs.Any advice or feedback I can get would be welcome. The mast is sitting in Koehler Kraft boat yard, which here in San Diego is the Holy Grail of wooden boats. Even still, I'd like to get some other opinions, if for no other reason to get my own head screwed on straight.

[Larks]

Hi Eric,
I represent Specialists Researching Environmental Social Scenarios Of Termites (SRESSOT) and wish to express my concern regarding your treatment of the species that you found resident in your mast...............

actually - read SRESSOT backwards, I just couldn't resist the take after seeing your pic's and thought I'd welcome you to the forum and wish you all the best with the project. I can't help with the mast but their are some great guys here who can so 'hope all is not as bad as it seems for the repair
cheers
Greg

[John B]

Scarfs are easy. 12:1 is good. I've done this sort of thing to similar spars.
It looks to me you could do some nice repair work with a router and a ramp so you could cut the scarfs into the rotten panel between the good panels. I'd do the same where that butt is as well ...get rid of that.. The little quarter of rot.. I think I'd just engrave a patch into. I'd rather see a disc of wood put back in than just filled with epoxy .
It seems dramatic but honestly its not hard once you get your head around the fact that a scarf is as strong as the original.;)

[Ian McColgin]

I've done lots of mast repair and it's easy, if tedious. Gouge the rot out where ever it is. Regularize the shape. I generally make vertically oriented rectangles. Get the sides parallel with each other and the ends 12:1 beveled. I'm happiest doing this by chisel but some who are used to power tools make some nifty jigs that guide a router. In WB a few months ago - anyone got the number - there was a nice idea that guides for both the hole and the dutchman. If the mast is hollow and the hole goes through, then the bevel can be guided if you use a pull saw to lay in kerf lines to chisel to.

Make a dutchman to fit standing a trifle proud. Do some test fits so it's really good. I use carbon paper here to show where I should be touching the plane or chisel.

Get masking tape on the mast to keep the epoxy off that. This is important because the epoxy is so much harder than the wood that it's hard to sand fair, especially at the bevel ends. I use robust gaffer's (duct) tape. Once you've planed or sanded the high part of the dutchman down really close, like clipping off the epoxy lying atop the tape, it will peel off easily and you can finish fairing.

If you're not familiar with epoxy, put some unthickened epoxy on the bevel surfaces and be sure it's well soaked up before final glue up. I like to thicken the epoxy as little as possible, going for a good fit instead of over-using epoxy's gap filling ability. A thick bit of epoxy is really a different structure than the wood, but a thin epoxy line will flex with the wood.

You don't want to just fill with epoxy. Epoxy behaves too differently than wood. You can use good quality fir even if the basic mast is spruce. It can't hurt to prime the whole mast with CPES before painting or varnishing.

Edited to say: Took a while to load the pix. You're on the right track, especially pulling out a whole side section where appropriate. Looks good.

G'luck

[redbopeep]

Any advice or feedback I can get would be welcome. The mast is sitting in Koehler Kraft boat yard, which here in San Diego is the Holy Grail of wooden boats. Even still, I'd like to get some other opinions, if for no other reason to get my own head screwed on straight.

So Koehler is allowing you to do the work on the boat yourself (or you're just trying to make sure that what Koehler does is the right thing?) I'd heard through the grapevine that he no longer let owners any serious work on their own boats there whereas it used to be a great yard for owners who wanted to do their own work, though.

Good luck on the project :)

[Jay Greer]

Ok RH,
Not to be the harbinger of bad news, but since what you are dealing with is what I have done for a living for many years I will make an educated comment that you are dealing with a fifty fifty project. That is, once you have messed with the old mast, you might just as well have built a new one. There is a tight balance of labor to repair vs. labor to build new. Often the repairs take longer and cost more than building a new mast or boat. Certainly, I would have that mast termite tented. That is the only guarantee that all of the residents will expire. So far as the rot is concerned, what has happened is, most likely, because there was not proper drainage built into the mast. The bee hole, "sheave mortice" was most likely not painted or sealed with varnish or shellack. Chances are that the mast also contains rot spores further down on the inside and all of your efforts are merely a process of putting a band aid over cancer. If you can rent a fiber optic inspection tool, you can view the interior of the stick. My gut reaction is that you would be better off building a new mast. I could, possibly, take a look at your problem as I am still in S. CA for a few days and do need to come down to San Diego on business.
Jay

[Thorne]

I don't have any experience with big wooden masts, but some of the guys at work do, and there can be a lot of surprises once they get older. The head of IT here just had the wooden masts replaced on his Cheoy Lee 41.

At work I sit next to a guy just returned from a 7-year circumnavigation, and some of the stories are pretty hair-raising...

If you were just daysailing that would be one thing, but if you really plan some serious bluewater sailing I'll guess that building new would be the way to go. Mast failure in heavy weather offshore could easily cause injuries, loss of the boat at the very worst.

[rebel heart]

Hey guys;

Thanks so much for the feedback so far. I'm trying to put all the pieces together in my mind, and get my options on the table. This morning, we found a new termite hole, about 15 feet away from the previous spot. No idea where they came in.

At the same time, I'm hearing from people that if we bag & gas the stick, and then epoxy seal it shut, it should dramatically reduce the live-ability of my mast as a termite banquet.

I'm going to get some quotes on a new wooden mast, and an aluminum. I'm sure it will be expensive, but as you guys said, I'd like to get all my options on the table. In the mean time, I'm going to keep sanding and doing prep work. Maybe I've seen the worst of everything, but I'll get some more options infront of me just in case that's not the case.

Thanks so much everyone, and I'll make sure to keep taking pictures, posting updates, and absolutely reading your responses.

[Dan McCosh]

I wouldn't pretend to make any judgments based on a few pictures, but I have done considerable mast and boom repair. You have a simple, box-sections spar, which is relatively easy to either repair or replace. The main benefit from repairing it is the cost of saving the wood itself. If there are two or three major scarfs, the labor of doing these, fitting, etc., could quickly equate to gluing up a whole mast.
One example of this is if the glue joints themselves are opening, and the whole thing can be split apart into its original stock. This was what we did for the boom. The original stock then was planed, and re-glued. Patches made more sense for the mast, which in our case is about 73 ft. with an oval cross section. The construction of a full building jig, plus the new wood, would have been substantial.

In your case, it's difficult to assess the current condition. Not being in a climate where termite abound, the issue has been water-induced rot. Spruce is pretty vulnerable, and the spots you describe more likely run some distance.

Another issues is that if substantial sections of the current mast are sound and well-glued, building (with long scarfs) even 25% or so new can be done with no loss of strength or appearance.

A friend with four circumnavigations preferred such spars, mainly due to the relative ease of making such repairs in far corners of the world.

[redbopeep]

Hi, again,

There are some sources of used-but-good-condition wood and aluminum spars here in San Diego. How long is the mast? If you can keep a wood spar, imho, it is best rather than going to aluminum.

:)

[rebel heart]

Thanks so much for your help so far everyone (especially redbopeep!). The biggest problem I've had over the last few days is a lack of prospective in regards to my overall options. I'm not a (total) idiot, so I'd like to think that if I had the options infront of me of:

a) Repair existing.
b) Have a new wooden spar made.
c) Find an existing wooden spar, and have it customized.
d) Have an aluminum spar made.
c) Find an existing aluminum spar, and have it customized.

, I could make a good choice in regards to what's going to work best for my situation. Redbopeep helped me out a lot in regards to my options, and I've got some investigating to do before I spend anymore money than I have already.

I'll keep this thread updated, and possibly will be asking some of you talented folks for a bid!