Soft spot on the deck

[Earl Watson]

Hi everyone,

I pulled the cover off of my CD 25 this week and noticed a soft spot has developed on the deck (top of the cabin all the way forward and right of the hatch).

There is some cracking in the same spot, which is also new and is the only crack apparent on the whole deck. Am I completely screwed here? What can I do to stop this from spreading. It's not anywhere near the mast, so that's good.

Thoughts?

Earl

[Joel]

It doesn't sound good. It sounds to me that what you are seeing are signs of delamination. From what I've read (which is quite a bit since I'm dealing with the same problem), it can be caused either by inordinate pressure or flexing which can cause a mechanical delamination or by water penetration which causes the core to rot. The latter is by far the more common. In your case, the cracks could have been caused by an impact that resulted in a mechanical delamination or could have occurred after, as the area became flexible due to a mushy core.

If the core is dry, it can be repaired by drilling some holes and injecting epoxy. If the core is saturated, it will have rotted beyond where you feel the mushiness. This is a lot of work to fix. Don Casey has an excellent book on hull and deck repair (called "Hull and Deck Repair") that covers all sorts of repairs. You'll also need to address the cause, i.e. if water got in through the cracks or around the hatch or some other fitting.

Good luck,

Joel
s/y Pokey II
'73 Ty #549
Bayside, NY



bondy_joelNOSPAM@hotmail.com

[Joel]

I hope I was wrong in my analysis above. In JimL's post today entitled "CD25 Mast support drawing and pictures...", he links to an illustration of the CD25 cabin top that shows a hollow area that might be where you are reporting the softness. Perhaps you don't have delamination but DO have an area of glass that needs repair.

Good luck.

Joel

[JimL]

Earl, based on what I could get to with the borescope, I think you've got an impact damage. Is the spot round, or does it have a crease? Use light reflected off a colored paper (maybe yellow or orange). Stand the color panel vertical near the damage, then angle the light onto the color to reflect on the surface. Move your view up,down, back and forth, and you'll clearly see shape and size of any depression. Also, check for imprint on the gel coat (witness marks) in the pattern of your cover. That'll help tell if it got clobbered.

I didn't get the borescope past the back edge of the hatch, but if you need, I'll try again. I was having a tough time getting myself oriented in there, and didn't really look much beyond the sides of the maststep area. I haven't seen any sign of balsa coring in the cabin top, but I'm not certain. I might be able to feed the scope in from the V-berth light, or perhaps drill a hole in the hatch opening....let me know what your damage looks like, after you check for impact.

Jim Leininger, CD25 #21



leinfam@earthlink.net

[John MacArthur]

Hi everyone,

I pulled the cover off of my CD 25 this week and noticed a soft spot has developed on the deck (top of the cabin all the way forward and right of the hatch).

There is some cracking in the same spot, which is also new and is the only crack apparent on the whole deck. Am I completely screwed here? What can I do to stop this from spreading. It's not anywhere near the mast, so that's good.

Thoughts?

Earl

You are not "completely screwed" here, but just in for a bit of work. Joel's note mentions a book on hull and deck repair, and West Systems sells a set of three pamphlets (West Marine has 'em on the same page as the West System stuff) on how to deal with this. I just finished a repair of a soft deck spot on "Stork", following these directions, and it came out fine. After I opened it up, I let it dry for a couple of weeks, and after that it took a few weekends of fussing around to get it right, but now it is good as new.



jmac@laplaza.org

[Earl]

It's definitely not creased. It seems roundish. BUt there is a crack in the gelcoat that crosses where the soft spot.

Earl

Earl, based on what I could get to with the borescope, I think you've got an impact damage. Is the spot round, or does it have a crease? Use light reflected off a colored paper (maybe yellow or orange). Stand the color panel vertical near the damage, then angle the light onto the color to reflect on the surface. Move your view up,down, back and forth, and you'll clearly see shape and size of any depression. Also, check for imprint on the gel coat (witness marks) in the pattern of your cover. That'll help tell if it got clobbered.

I didn't get the borescope past the back edge of the hatch, but if you need, I'll try again. I was having a tough time getting myself oriented in there, and didn't really look much beyond the sides of the maststep area. I haven't seen any sign of balsa coring in the cabin top, but I'm not certain. I might be able to feed the scope in from the V-berth light, or perhaps drill a hole in the hatch opening....let me know what your damage looks like, after you check for impact.

Jim Leininger, CD25 #21