Repairing a Wooden Mast

[Hampus]

Hey!

We just bought a new boat and it has wooden mast. All my other boats had aluminium. The mizzn is in excellent condition, but the main is suffering from wood rot just above the foot and around 1' up. It's a spruce box mast that is stepped on deck. The rot is worse around the corners of the mast and on two sides I can poke a knife right through it without any troble. It's good enough on the sides though and it stood during our 150 miles home in a force 8-9, but we really need it fixed. We're setting off on a 2 month cruise, starting in august and we are likely to see some autumn lows coming our way. There is an excellent wooden boat builder around here that could do the job for us, but he has too much work on his hands and his oppertunity is in mid august, which is way too late for us. I'm fairly handy and I know at least the theory around replacing parts of a mast. I would have to replace around 5' of the mast on all four sides. The only place I can work with the mast is on the dock beside the boat. is it at all possible to do it on location with electrical hand tools and how would I go about doing it? It's scary, since a broken stick is the last thing I want but I still trust myself more than I would any company without documented experience. Suggestions please!

/Hampus

[Amgine]

This is a tough call.

I rebuilt a near-solid mast with a clothes-pin splice due to severe rot at deck level (keel-stepped mast.) This was simpler than delaminating the affected portions, removing the rot, and re-building. However, I've never actually worked on a box mast.

However, with your box mast you may very well be doing exactly that. The lower portion of the box should have a near-solid plug inside, which may also be experiencing rot. The box should have taper, probably on 3 sides, so it's not likely you could simply cut off the bottom and slide an insert into place.

The best practice would probably be to delaminate the box, remove just the rotted lower portions of the mast strakes and splicing in replacement wood, then re-gluing the box together. (Make sure the scarfs are staggered, so you're not creating a weak spot.) This will also give you the opportunity to inspect/replace the wiring, the attachment for rigging/sheaves, and add aluminum foil to the inside of the mast creating the largest radar reflector you could possibly have.

But, as I'm sure you can tell, this won't be a quick and easy project. I think building, or rebuilding, a mast is something a reasonably handy person can manage, but xe would probably prefer the peace of mind of having a craftsman do this work.

[Wotname]

It sounds like it will have to be done outdoors, if so, what are the expected weather conditions?

You can control the level of workmanship, tools, design of repair, materials etc but you can't control the weather .

[Hampus]

Hey and thanks for your replies. In desperation I called every single shipyard within a couple of days sailing distance and found one just 71 NM away. They have rebuilt and restored seveal old gaff riggers and could take my mast in for repair in just two weeks. If only it stands a 71 NM sail Doing it myself is still option number 2.

Outdoors it would be and in worst case I could build a cover around it.

Thanks!

/Hampus

[PirateBarnabus]

Hi, I have recently aquired a boat with a wooden mast. It seems in fine condition but i wondered if anyone had any tips about maximising the protection at the bottom wher i would have thoiught that any trouble might start. I have seen mast boots and tape etc but I would be nervous about trapping moisture in as much as keeping it out. The Boat is in a warm climate so that helps I suppose.

I have also been told that the best Varnish to use is 'Epifarnes', which I intend to apply as last seasons sand and varnish operation did not last the rigours of the winter very well at all.
Regards
PirateB

[Randy]

Pirate Barnabus - epoxy.
Hampus - I can't imagine doing a repair like that dockside. The boatyard if they're good is a great option I think. Doing proper scarf joints isn't real simple at the dock.

[Amgine]

I only had a few years with a wooden mast, so I am by no means an 'expert'. However, here's my experiences:

'Warm climate' tends to accelerate rot and sun damage to the finish. Best way to avoid rot is to keep the step dry. My boat's mast had been stepped in old dolphinite compound, including all the nasty chemicals which they're no longer allowed to use, and was perfectly clear of rot. however, it had rotted at the partners under the wedges and below the mast boot, probably because the mast had not been regularly removed and the finish restored there in the wet.

When I repaired the mast I applied 6 coats of varnish. I applied an annual coat the next two years, and was about to pull the mast to inspect when I got rid of the boat. In between I did varnish repairs as necessary. This was in PNW, with low sun damage to the finish.

I don't think there's a 'best' varnish. I personally prefer, for this purpose, an oil-based varnish which does not require surface sanding for adherence, so I can go up on the bosun's chair and varnish on my way down in a single step for a coat. Whatever varnish you are familiar with, enjoy working with, works in your location, and you will maintain regularly is the varnish you should use in my opinion.

[clockwork orange]

Wow,talk about timely,i am doing pretty much an identical repair right now on a customers 47ft Luders yawls main mast,in this case the first thing i did was mesure up from the butt and put a mark on the mast as a reference point above the area of repair.I then cut off the bottom 17 inches to get past the rot and planed it square. This mast is built exactly as described in Amgines reply. The mast has fwd and aft staves of 3" thick with 2" side staves and solid blocking in the center.I have planed 36" long scarfs on the fwd and aft staves which is a 12:1 ratio. The center blocking piece which is 17" long is just butted to the bottom with a large dowel pin for location and is sandwiched between the fore and aft staves,i considered scarfing the center block in the other direction but as it is pure compression in this location i felt a butt would be better suited. The scarfs are not staggered which i would have done if the repair were in a location further up the mast but it was not feasable here,however as a guy who spent a lot of his earlier boatbuilding career building cold molded sailboats i have a lot of confidence in glued joints with correct scarf ratios.We are using vertical grain douglas fir instead of spruce due to availability and cost and remembering that while sitka spruce is the lumber of choice for spars and it has very good strength/weight it is not a particularly strong wood nor rot resistant.
Steve.

[mevysen]

Greetings one n all,
I realize these posts are a few years old but I'll ask anyway, when you glue a boxed mast of spruce back together which product is the one of choice and what preparation does it require. I have an Angleman Sea Witch and both spars are De-laminated due to a friend over tightening the dead eyes. Can this be re-glued with the masts in place. With the use of Spanish windlasses and 5200 for example?

[forsailbyowner]

In my research for an upcoming wood mast project I read hi heat resorcinol (sp?) Is the only glue that should be used for building/repairing a wooden mast.