Floor Beams

[sedelange]

While sealing and torquing the keel bolts, I discovered the fiberglass surrounding the floor beam under the mast had delaminated on the aft side.  We cut off some of the glass and found the most of the aft side was completely separated.  The good news is the wood is not rotten.  The bad news is the wood is very wet.  Any good ideas about drying out the wood?  How dry should it be before we reapply the fiberglass?

Steve DeLange

[Jon Schneider]

I'd love to understand this a bit more.  What do you mean by "floor beam"?  Are you saying that the bed (i.e., floor) of the bilge is cored?  I didn't know that.  Or are you talking about something other than the bed, perhaps a stringer?  If it's the bed, I think you need to cut out as much of the core around the keel bolt as possible and fill the void with epoxy (you'll have to treat the bolt with mold-release wax and create a bit of a moat around it) just the way you'd treat the cored deck around the chainplates.  Don Casey's "Sailboat Hull and Deck Repair" has an excellent description of this technique.  Take pix and show us.

[Ron Hill]

Guys : What Steve is talking about is the keel sole box that the mast or compression post shoe sits on.  The early 1986/87/88 before hull #700? C34s had this keel sole made out of wood.   
Any crack in the keel sole or the PVC pipe connecting the fwd bilge to the one just aft of the mast will allow bilge water to migrate into that sole.  There's a write up in the Mainsheet tech notes on this topic.

Steve's in good shape as he said that his wood is not rotten.  If it were he'd have to dig it out and fill it with glass or epoxy.  What he needs to do is chip off all of the loose fiberglass/mat.  Then re mat and reglass that area.  It's an item that needs constant inspection.  Another reason for a dry bilge.   

[sedelange]

Ron:

Thanks for the improved description.  We have ground all the delaminated glass from the beam.  The other beams seem to be intact.  I am still concerned how to dry the wood sufficiently without removing the floor and the remaining glass covering the wood.  A big problem is the boat is currently sitting under a plastic cover with all the windows and fittings removed being prepared for paint.  I think I am going to have to wait until the paint is finished and all the hardware reinstalled so I can heat the inside of the boat to dehumidify it. 

Steve

[Stu Jackson]

You may also want to consider some epoxy coating before you re-glass.  If there's any question about the wood, try "Git-Rot."  A hair dryer or any other kind of low, constant heat over a period of time should do the trick.

[Rick Allen]

I unearthed this old thread because we are going through this same exact issue now with my boat.
During an insurance survey last week we discovered a small "separation" in the gelcoat running fore/aft in the bilge. The glass slowly delaminated and caused the wood below to swell.  Since I needed to pull the boat out for bottom painting, we decided to tackle the problem head-on.  The prior owner never installed an automatic bilge pump (he said he didn't "believe" in them) so the bilge was wet from 1988 until I bought her in 2005 and installed 2 pumps. But it looks like the damage was already done.  We're having the wood removed and a new matrix installed over and glassed in.
What I thought was interesting was that there was no glass or epoxy around the keel stud holes (though the wood).  One would assume that the holes were drilled and refilled with epoxy and drilled again as to not let water seep into the wood at the studs.
I've taken extensive pictures of the work so far and they are at my website here:
http://public.fotki.com/Sailorick/sv_painkiller/bilge-de-lamination/

I figure (Like Stu) that a picture is worth a thousand words!!

To date we have ground off the glass and are preparing to cut out the wood this week.

Thank God I already put my kids though college!

[prh77]

This concerns me. I do not have any indication of a problem, but wood in the bilge? What were they thinking? I always have water in the bilge due to rain coming through the interior of the mast. If this wood rots,is it a structural problem?

[Ken Heyman]

Ron,

Do you remember the year of the tech notes article? I'm due for an inspection as well.

thanks,

Ken

[Ron Hill]

Ken : As I recall there was mention of the compression box under the mast and the year production hull (about #700? in 1997/8?) that Catalina changed from the wood they were using.  Gerry Douglas was elusive about what they changed to and I mentioned that Catalina probably threw away more resin than it took to build a fiberglass rather than a wooden mast step! 

I believe that I do have a Catalina drawing on the keel sole.  Let me see if I can find it. 

[Rick Allen]

Thanks Ron, That would be helpful..

[Steve Sayian]

I was on a business trip to the Raytheon facility in Largo, Florida this week and stopped by the Catalina production facility for some information.

While I was there, Gerry Douglas gave me a new version of "The Art and Science of Building Catalina Yachts".  In the brochure, they talk about the mast supports system "Typical Mast Support System.  Catalina's unique mast step compression post construction delivers the benefits of a deck-stepped mast: less mast noise in the cabin, a dry bilge, more interior space, and the compression strength of a keel stepped-mast." 

There is a drawing that shows the compression post resting on a laminated fiberglass grid structure.  The sturcture is laid up over a fiberglass reinforced structural foam beam. 

I remember an article in Sail Magazine a few years back about how Catalina's were built and it showed foam 'beams' glassed into the hull and then covered with mat and roving.  These 'beams' provided lateral stability and rigid surfaces for the mast compression post and interior liner mountings.

When I get to the offce Monday, I'll pdf the brochure and send it out.

Steve

[Stu Jackson]

Ron sent me this info from Catalina.  I've forwarded it to Rick.  I've posted it in as large a file as I could, so if you need it, download it by copying and pasting.  I just noticed that the maximum file size you can post has been increased from 75 KB to 195.  That's great.

[Rick Allen]

Thanks Ron and Stu!!  This helps immensely!! More proof that this site and it's members are incredible!!

It's too bad Catalina isn't treating this repair like a "Recall"..