Old log needs New Stringer.

So I have an elderly Jacobs I purchased last summer. It’s a 10’4", has this great channel or concave running 18" up, down thru the tail. Has a big black fin, sort of wedge shaped. Looks like it will be fun one day…

So whoever owned it back in the day let water seep in thru the wood tail block and the 2" balsa stringer soaked it up and rotted and shriveled like a mummy's leg. I knew it was bad when I bought it, and the guy selling it made it perfectly well known that something bad had happened. The seller posts on here I believe. 

  A few weekends ago I cut the glass on the bottom up the 18-24" to where the balsa looked good. I got the glass to flap open and pulled out the old shriveled wood. I am figuring on just up and replacing the balsa. Pure and simple. I found a place that sells 2" x 4" x 36" blocks of balsa. The foam is alright except for some mold. I'm planning on cutting the joint between the old and the new to resemble a V shape, and glue it together with some "Git Rot" which can be purchased from West Marine, or the boat place down the street. I'm thinking of just relamming the old glass to keep it more uniform looking  when completed. 

I did a crazy job like this on an old Hansen when I was in High school using the Git Rot. The stringer was in better shape, but the finished job was rock solid.

I'm going thru the trouble because I think the board will be a hell of alot of fun, Hap might appreciate the effort, and it will be a challenge. 

What do y'all think.

I think you ought to take lots of pictures and post 'em up. That’s what I think you should do. Yup. Then, once done with the board, I think you ought let me try it out. In the box.

Kidding. Can’t wait to check it out. Neira, who posts here, seems like an ace repair guy:


No Logs in the Box Bubba!!

I’ve had to replaced complete stringers on three of the boards I have restored. Your plan sounds feasible to me. The old dry rot gets them in the end. What is Git Rot? platty


You did the Whole stringer then. Maybe that is the way to go, huh? Git Rot is a two part goo that you work into rotted, compromised wood. It penetrates the fibers of the wood and sets up as a super tough, dense rubber. It has a little give, but that is maybe good for the application.


Just found this while doing a search on Git Rot. I haven’t opened up the board much further past where the wood “looked” good. It was a bit soft and It may need to dry out for a bit yet. But I certainly plan on doing the Joint where the old stringer is in decent shape.

Platty, do you have any more pictures?

Oh dear- what you have is definitely why I never liked wide balsa stringers- they soak up water like a bricked camel and this is precisely what happens. Balsa in its natural, in-the-tree state is something over 50% water, and you might say it really, REALLY wants to be that way again.

Now, personally I will have nothing to do with any WEST product, lots of very good epoxies out there for this purpose and you don’t need to pay their WEST ripoff premium prices. System Three, for instance, makes their Clear Coat resin for this sort of thing and there are lots and lots of others. And here’s how I would approach the problem;

You will need some strips of 1/4 inch plywood, call them 4" wide by the length of the rot plus some length for ‘just in case you find more rot inside’, a plunge router with a collar ( as is used with jigs and such - Ryobi makes a cheap one that’s more than adequate for this and any woodworkers store has the collars ) and a hot glue gun and lots of glue sticks.

Carefully mark out alongside the stringer on the bottom, offsetting for dimension A above. Use hot glue to stick your ply strips down, go a little nuts with it, you don’t want those puppies to move. And it might not be a really bad idea to go maybe 1/8 oversize on width. That’ll get rid of the old stringer glue as well, which is probably Pretty Ugly by now.

Now comes the tedious part. With many passes and slowly increasing the depth, rout out the rotted wood and go fairly well into good wood, cutting through the glass too. Note that I show the router bit not going all the way to the bottom - you will want to scrape out the last of the rotted balsa with a narrow paint scraper and watch out for the sharp edges of the glass you just cut. If the rot doesn’t go all the way, then taper the end with a sharp chisel so you can make it look good where new and old meet. I don’t think you can save the old glass, plus it’ll look like hell on top of that nice new wood.

Pop the ply strips with a putty knife, don’t worry about hot glue residue just yet. Put in your balsa, ripped to the right thickness and as close to the nose-tail deck curve for that section as you can come plus some extra thickness for planing - whatever you’re comfortable with, slightly rounded on the deck side ( a light sander and coarse paper is a good way to go for this) . Bed it in epoxy, use plenty. Remember that the balsa will soak up epoxy almost as well as it’ll soak up water.

Okay, I’d then use a belt sander to take down the balsa to ‘close’, one of the few uses for a belt sander anyplace near a surfboard. Finish with a random orbital sander, taking off the hot glue and excess epoxy as well. Glass a strip on to bridge the gap - I’d use a couple layers of 10 oz Volan, the first maybe 4" and the second at 6-8" wide, the edges of both layers well feathered with the sander - hotcoat,sand, gloss and go surfin.

Oh, before it slips my mind:

Now that you have your nifty new plunge router, and as you got rid of the old fin sometime in the process, I’d rout in a nice new Fins Unlimited/Bahne box in your new wood rather than trying to re-use the old fin in some way. Same deal about making a fin-box routing jig as with the strips above, it wants to be oversize by dimension A in all directions, so that it’ll fit the fin box nice and snug

leastwise, that’s the way I’d tackle it…

hope that’s of use


Thanks Doc,

  Most of the for has already pulled away from the foam, leaving only the glue (old natty) on the foam. I'll probably clean it with some dragon skin or 60 grit. Up where the wood is marginal, though, I might employ your method. I'll try to get some pictures up of this thing, because it's a really neat board. I will deffinatly stick with the old fin though. It's not going anywhere that I can't drive, so no need to futz with the fin.  

Gotta run, work calls!

Platty, what great cheap clamps you have. Sometimes the simplest idea is the best. K.I.S.S

fantastic method Doc, and VERY well explained too, only on sways could you find people willing to put so much effort into a post reply, you’re a champ.