Termite damage

[Kevind767]

Hi All,
I have a 1983 38' Convertible III with termite damage to the bulkhead between the engines, and the fuel tank.

Just about impossible to get in and scarf in new plywood to repair it properly, without removing engines.

Git-Rot has been suggested, but does anyone have experience, 1) with this type of repair, 2) what product would be best to use?

Thanks for any in site.
Kevin

[Rawleigh]

Is there room enough to epoxy another piece of plywood over the damage to sister it?

[Carl]

I believe I heard here that Git-Rot is nothing more then thinned epoxy resin.

That said Git Rot is sold in the correct ratio with nothing extra to add.

My boat had the old style wood deck and hatches that each year got a little bit softer and I started using Git Rot to fix...repair.
And it did fix the issue at hand and it did last but the area next to it became the new problem area...or the other part of the floor, a hatch an upright support. Finally, I just pulled it all up and put down a fiberglass deck.

So yes it works, it adds weight, but it's pretty strong...you can add saw dust to mix to fill voids.

[Tony Meola]

Like Rawleigh said if you can laminate another piece in there that is how I would do it. But at some point you will need to bite the Bullitt and pull everything apart.

[Carl]

Building is not my thing, so I take my thought process for what it is.

If the bulkhead has been compromised by termites, they entered from the bottom or sides, no?

The center section your going to cover (sister) is going to adhere to the compromised wood panel...while the new wood will be strong and bond to what's left of the original panel...the bond is only as strong as the wood from the original. Plus you are not adding any structure to the compromised areas you cannot reach...like the tabbed sections that are bonded to the hull and stringers.

Just thinking if we have a beam supported by two pillars, the beam has been eaten away and starting to sag in the middle. To fix do we add a sister to "just" the middle to stop the sag or do we make sure the sister is long enough to be supported by the pillars as well?

[Kevind767]

There is room to epoxy in a sister, but will need to remove copious amounts of wiring, lines, and everything else attached to the bulkhead.

Don't want to do that , if I don't have to, as then that will be a real PITA.

This bulkhead does not appear to be a load bearing structure, so I did not think it would be a bad idea to inject the epoxy.
Just looking for ideas.

Thanks everyone.

[Amberjack]

I used Git Rot years ago on my first large wooden boat. As I remember it does come in a syringe looking applicator which is really just a two part mixing device without a needle so there is no "injecting", you simply squirt it onto the affected area and (hope) it absorbs into the surface. If this area is hard to reach it will be a mess and you want to be sure to not epoxy your wiring etc to the bulkhead. It can add some structural rigidity in areas but nowhere near the original. That said if not urgent, maybe just be sure the termites are eliminated and just leave it for a future project.

[Tony Meola]

I am not sure how the 38 was built and what function those bulkheads serve. Normally they support the hull and keep it from flexing and collapsing. I have always been told the 31 is built in such a way that the bulkheads are not really needed to support the hull.

If you know a marine surveyor, I would ask.

[Anthony]

Not sure if this helps or not On my 38 the bottom of the rear bulkhead was rotted cut out the bad bulkhead and the sill. Dug out as much rotted wood as I could and filled with a mixture of glass and filler and epoxy. Glassed all the way to the top and capped it with teak and repaired rear bulkhead. Seems pretty strong and a lot easier than replacing the whole thing. That rear bulkhead is a bad design. Hard to keep water out.

[Kevind767]

Anthony,

You are correct on the fact that the plywood bulkhead is a bad design.

Overall been happy with the boat, but the way it was put together, makes me wonder why Bertram had such a good reputation.

For just little extra work, it could have been done so much better.

Sigh,
Ya I know I'm dreaming

[Tooeez]

I've used Git-Rot for repairs for over 40 years--it's a great product, but only if it's applied correctly--and it's not easy to use. But done right it is as close to a permanent repair for rotted wood as you can get without surgery. The last big repair I did with it was the rear cabin bulkhead on my 28---at the bottom the wood core was just about gone, leaving just the formica on the inside and the outside. I drilled 1/4 holes on the inside surface, about a foot up from the bottom, and filled it with the Git-Rot. Ten years later still holding fine, with no additional rot.
As far as I can tell Git-Rot is just a thin epoxy. It is expensive, and it does not go very far, especially if you have a big area to repair. I think if you could thin out regular epoxy it would work just as well.
Application is a mess unless you are prepared. This stuff works by running into any voids it encounters, and capillary action will draw it into any spongy wood. That works great on flat, horizontal pieces that are not too thick, but it works against you with a vertical bulkhead. If there are any openings, gaps or holes at the bottom the epoxy you inject at the top will just run out the bottom--and sometimes it doesn't start leaking right away, it waits until you have a decent amount of product inside the piece, and then starts coming out and won't stop. If there aren't any gaps at the bottom, then the space is full of air, which has to escape in order for the epoxy to run in. If the voids aren't big enough to allow the air to bubble up the epoxy will harden on top of an air-filled void.
Here's what I've learned to do: I start by sealing the bottom of whatever I'm working on as best as I can. The seal isn't meant to be permanent; just enough to hold the product in until it cures. On something like a bulkhead I would use a cheap waterbased widow caulk, like Dap, where the bottom of the bulkhead meets the hull. Determine, as best you can by tapping and drilling small exploratory holes, the extent of the damage. I use disposable syringes to inject the epoxy, starting from the bottom up. I drill holes the size of the nose of the syringe (or the size of a piece of tubing that fits the nose of the syringe) along the bottom, and another set of holes up about six inches, and another set above that, as far up as the damage extends. I have self-tapping screws that fit those holes at hand; I inject the epoxy into the bottom holes, slowly, until it begins to come out the holes above. I then remove the syringe tube and plug the hole with a screw, move the tube to the hole above, repeat until the epoxy comes out the hole above that, then plug that hole. No matter what you do it makes a hell of a mess--have lots of rags and acetone on hand.

[Tony Meola]

Anthony,

You are correct on the fact that the plywood bulkhead is a bad design.

Overall been happy with the boat, but the way it was put together, makes me wonder why Bertram had such a good reputation.

For just little extra work, it could have been done so much better.

Sigh,
Ya I know I'm dreaming

Kevin

It all comes down to dollars and cents. A few years after we had our 31, the steering block rusted out and broke. While replacing it, we found that the two Angle Iron pieces they attached too was pretty rusted also. When I ordered the new blocks from Bertram, I asked them why wasn't the angle iron support made of Stainless. The response I got was that would have added some extra money to the price of the boat. Ugh! We replaced them with Stainless angle iron.

[Carl]

SS angle is extra cost upfront. Steel angle is usually structural Hot Roll Steel, about the cheapest material available.
SS angle is a "little" less available. By no means difficult or rare to find...but not always from the usual local supplier.
Cutting and working with SS is a "little" bit different...if not treated a "little" bit different it can cost "A LOT" more in lost time and tools.

Running a "one off" for yourself...it is not a big deal if you spend an extra $10 on a small piece of material. Then spend an extra half hour or hour making it as you have all day, all weekend it is somewhat irrelevant and you have little to compare it to. Using your chop saw or sawzal, hack saw...chances are you were going through a blade and drill bit anyway, so again what is the big deal.

That said...it would be nice if they did it right from the start.

[Bruce]

My father who was an engineer for FORD and traveled frequently to various Ford plants for production issues once told me when I asked when I tore my first car apart at 13 about doing things the correct way and he said, there is a balance between costs, doing it safely and making it bullet proof. For every extra dollar something costs, times that by production amounts and you either have to eat the cost to remain competitive or pass the costs on and risk losing customers.

Not only that you have to find suppliers who will supply the material specked out consistently and find part manufacturers that will supply those parts to you the builder. What seems like a simple idea, when engineers are involved becomes complicated he used to say with a smile.

[Tony Meola]

Carl

Actually we purchased the Stainless angle iron at a machine shop. Gave him the old ones he cut it to size and drilled the holes for us so it all lined up. Unfortunately I do not remember the cost, but it probably was around 1980. I remember thinking this was cheap, I wonder why Bertram would not have done it. So it could not have been that much money.

[Pete Fallon]

Kevin767,
Make sure that you get all the termites out of the boat or they will continue to destroy the rest of the wood in the boat. If you find anything that looks like coffee grounds around the cabin sole or inside cabinets the boat still have termites have the boat tented or use a good grade bomb. I have surveyed a lot of Bertrams especially in Miami that had major termite infestation.
Pete Fallon

[Tony Meola]

I have never seen a termite on a boat. How the heck do they get on a fiberglass boat that sits in water part of the year? I know they fly in the spring, but really, I would think they would die before they located the wood. I figure if a boat sat on land long enough they might build a mud tunnel up to the hull and sneak in one of the openings but that would be a heck of a mud tunnel.

[Kevind767]

Gents,

As Aways, thank you for your responses, and knowledge.

The termites are definitely gone, just the damage they left behind has to be dealt with.

I do like the idea of plugging the holes starting from the bottom of the damage, and working up from there

Would a wooden plug or bung, work better than a screw?

I'm not looking forward to doing the job, but gives a bit of hope that it can be done.
(Said tongue firmly in cheek)

[Tooeez]

The epoxy is going to try to escape as fast as you put it in. I think the screw will seal better, and can't get knocked loose if you bang into it while working on the next set of holes.

[Seapalm]

Kevind,
I’m across the bay and have a ton of glass, epoxy and wood experience. PM me and I will be glad to help.
Cheers!

[Seapalm]

Kevind767, PM sent.