mast compression question

[john day]

my Sun Cat mast terminates inside bow locker.....the question... is there any support[compression support or post] underneath  the  bottom of the bow locker?

John day s/v sweet

[Galnorth]

I found this out the hard way a couple of years ago when I had an issue with my 2001 Sun Cat.  In my boat under the fiberglass bottom of the locker there is a piece of plywood (I think 3/4 or so) supported by a plywood grid filled with structural foam.  I assume the grid goes down to the keel but I didn't dig down that far. 

I bought my Suncat used from, I think the second owner.  A few months after I got her I realized I couldn't get the shrouds tight.  Further investigation showed the mast step was compressing the bottom of the locker.  There had been water intrusion into the locker for a while,  I believe coming down the sail track which wasn't caulked at the deck.  The water got under the fiberglass in the locker and rotted out the plywood under the step and when the plywood got mushy the step pushed the fiberglass down.

After dropping the mast and pulling out the stub I cut the fiberglass out of the locker bottom and took out the rotted plywood locker bottom and a fair amount of wet structural foam.  On problem with the foam is that it kept the moisture in place everything is enclosed so there was no where for it to go.  After everything dried out I replaced the plywood and the foam and reglassed the bottom of the locker.  Finally I added a 1/4 piece of aluminum plate that fills up almost the entire bottom of the locker and mounted the step on it.  I was very careful seal any screw penetrations and now always monitor the locker for any water intrusion.  So far, so good.

[john day]

Thanks for the heads up . I did a good job of sealing the mast to deck and sail slot .  My boat is stored with the mast up.  [with no plug inside to block leaks at the tabernacle ] .
Moisture continues to show up in small amounts, my next step is a mast plug . Any ideas...?

[Bob23]

Is this a problem with older Suncats or all of them? Strange...

[kickingbug1]

  seems like a bad design----older boat or not i think hutchins deserves a call.

[Tom L.]

All boats that step the mast through the deck (keel steeped) can have water intrusion issues. Care must be taken to keep that from happening. I have a 01 Sun Cat with no issues at all. The deck collar is sealed as well as the sail track tunnel in addition I keep the boat covered with a tarp that works with the mast up or down.
So it's not a design flaw but a maintenance issue that must be addressed.

Tom L.

[john day]

My solution to water trapped inside the mast , after lowering the mast , was to extract the trapped water with a 5ft long  pipe, duct taped to my shop vac--and pushed to the bottom of the mast stub . There is no water intrusion with the mast down .  I have a sunbrella cover [ think knee brace]  for the mast hinge. Com Pac also offers a custom plug for the mast stub that works well.  My concern is the accumulation of water with  the mast up, and if possible prevention.  Dropping the mast works,however since I dry sail the boat dropping the mast is not necessary. The boat can be stored with the mast up on the trailer.

John s/v 'sweet'