Mast Column Bilge Keel Fixes...

Starting at the very top, here is some owners experiences and great fixes.

Take a look at this link for what I've done so far. http://picasaweb.google.com/danlmetzler/MastCompressionBlockRepair  I don't have the fiberglass wall that Max has, that's for sure, and I'm also convinced that my boat was not previously repaired, maybe it was just a difference in the factorys techniques, the boat builders techniques, or someone removed the fiberglass wall from my boat but I couldn't imagine why and there is no evidence of anything that used to be there.  It's not the prettiest repair, I still have to fiberglass and paint, but it's rock solid for sure, and my deck is where it's supposed to be again, head door latch lines up and everything!
Dan Metzler,1985 TRBS #4328
 

The deck step and the mast column showing the thru deck tube, open column and base openings. (click here) Bruce n Jacky Kachline (currently off cruising!)\

Here are some quick sketches of a fix for the rotten mast step support (bilge block), and how I did it. Rather than the typical wooden block replacement, I constructed a Stainless Steel (SS) unit for long life!

1- The mast was unstepped to remove the load from the compression post.
2- I removed the rotten block by chiseling it out. It was easier then I thought as most of the wood was rotten. Be careful not to cut any of the wiring that comes down through the block.
3- I made a cardboard template of the bilge and one of the underside of the cabin sole. These were duplicated into 1/2" stainless plates. A slot was cut in the front of the top plate to accommodate the mast wiring.  (Diagram 1)
4- Two, 1" sq. stainless blocks were bolted to the underside of the top plate and two more to the top of the bottom plate.  (Diagram 2)
5- Four 1" square post were cut to fit between the plates.
6- Put some West epoxy under the bottom plate and on top of the top plate. While still wet, a small screw jack (uses for belt tensioning) was put in the middle & cranked up tight. Then the two forward posts were push in and bolted in place. Then the same with the two aft post. The jack was removed.

This may be a bit of over kill, but it seemed easier then trying to force a wood block back into this space without cutting the cabin sole or leaving so much space that the whole thing would settle under load.

Bob, Xanadu '88 TRBS #5333 Pelham, NY

And at the very bottom, here is the Catalina Yachts plan for repairing the wood filler in the bilge! ( Bilge Keelbolt  Fix )

There was a conversation on another forum about replacing the block under the mast compression post and someone had suggested the MKIII boats had replaced the wood block with a fiberglass block. I posed the question to Catalina and heard back from Warren and Kent. They said that all C30's, regardless of model, used a white oak block fiberglassed in place. If you find rot in yours Catalina sells replacement blocks for $165 (pics below).

http://www.njlakefront.com/c30/cp1.jpg
http://www.njlakefront.com/c30/cp2.jpg
http://www.njlakefront.com/c30/cp3.jpg
http://www.njlakefront.com/c30/cp4.jpg