Wet Stringer Disease

[bobwpe]

Way back in May when I was drilling the holes in my stringers for the engine mounts, I noticed varying degrees of moisture in the drill shavings that came out. After a few days of denial and hoping the stringers would dry out through the drill holes, I decided it was time to face up to my newest desperate situation.
I searched this forum and found what I was hoping for in a post by gcarter where he mentioned cutting a groove at the base of the stringers, sealing off the area, and running a dehumidifier for a few weeks. I ran this by my glass guy and he said he'd had success with this in the past, but suggested I cut away a one inch wide strip on each stringer to provide more surface area for the dehumidification. I did this in the area between the transom and forward bulkhead of the engine compartment, put in a closet type dehumidifier, sealed the area and waited. I also bought a Delmhorst J-Lite moisture meter so I could get a relative indication of my progress.
In the beginning, the meter pegged out at 30%(its maximum reading) moisture content in about 1/3 of the areas I checked and was between 15-30% for the remainder. I ended up letting the dehumidifier run continuously for 12 weeks during which time I drained about 1.3 liters (approx. 46 oz.) of water from the dehumidifier resevoir. The area shown in the photos below (before, after, and glassed up) was by far the worst and the meter remained pegged at 30% for about the first six weeks so it was probably significantly higher in the beginning. In the end, it was in the 10-12% range and the other areas were below that.
I'm really glad I did this and feel it was well worth the time and effort even though it blew my summer schedule to pieces. I also want to thank gcarter and this forum for getting me started in the right direction.

[MR MAGOO]

Very interesting, fantastic results. Thanks for sharing the info!

Kurt

[Mr X]

Why not cut out the old wet stringers and glass in new ones?
Would have taken less than a week, working in the evening after work.
If you want step by step help, I and many other's here, could easily walk you through it.

Just my 2 cents.

[bobwpe]

Thanks for the suggestion but I really felt replacing the stringers was beyond me experience wise, especially since the new fuel tank is already foamed in. If the problem was more severe or widespread I probably would have had no choice, but this seems to be a good alternative.
If I was smart, I wouldn't have gotten involved with this at all and just bought your X-18! That was one sweet deal.

[gcarter]

Glad I could help.
This method is also useful when the deck is still on.:bonk::bonk:
I got the idea while researching osmotic blisters and how you have to dry the 'glass before repairing the blisters.

[BigGrizzly]

Here is another tidbit. After this is done slice the top of the stringer and fill it with Get-Rot. This really strengthens it up. At first I though it was a stupid Idea, but my mom said it is my boat so just do it!!!. That was 30 years ago and the 16 is still alive and solid. After that my Dad must have bough stock in the company, because every time a dry rot situation showed weather at home or on a boat out came the dry rot..

[gcarter]

Get-Rot is great stuff Randy.
There's been many a wooden sail boat saved with Get-Rot.

[hardcrab]

not to split hairs but, I believe it's called "Git - Rot"

[gcarter]

No matter how you spell it, it works really well.

[Pismo]

Some sort of heat application as well as the dehumidifier would have sped things up greatly.