Joint Decision: Mast Post Dribble

A couple of years ago, we noticed a slight dribble down the compression post during heavy rain. This is only apparent when on the water (hence during one of our mini cruises) as normally JD has a tarp draped over her entire length to protect from the Florida Rain,Sun and dust/debris from nearby State Road 7.

Today I decided it was time to fix it. Cloudy day and a bit of a breeze meant it would be nice to work under the tarp. So out came the Cap'n Tolley's Creeping leak fix and a re-read of the instructions.

First step is to make sure the area is dry can clean. So armed with paper towel I crawled beneath the tarp onto the cabin top. Dry! But taking a closer look under the Stainless Steel mast base plate, I noticed that the bedding compound had shrunk and guessed that was the cause of the dribble.

Not wanting to overdo the Cap'n Tolley's, I decided I would first clean out the excess compound.

So out came my Stanley and out came the excess compound.

Now it was clear that the shrunken compound was the culprit! I decided to go for it and remove the compression post, do a clean up and fix this issue correctly.

Clamping a vice grip to the nuts on the underside of the cabin deckhead, I removed each of the 4 screws. They are only threaded for about an inch, the rest of the shank is plain. So once the nuts were off, I could pull the screws out with a pair of pliers.
To get the compression post out, I inserted a piece of 3" timber from the front of the mast base and used that as a lever to rotate the base and post. It was easy!

You can see how grungy the space under the base plate is in the pic. When I pulled the post all the way up and out, there was just room below the tarp with the mast in the raised stern crutch. I still had to use my head to lift the tarp the last few inches, not a big deal. Time to clean up the area.

The blue tape is on the stbd side of the mast base and is used as a reference in the pics that follow.

Notice the inconsistent structure of the sealing compound left on the deck. I'm guessing this is 3m 4200 compound. But that's only a guess.

Another pic before I pulled the post all the way out. Notice the ring of mild corrosion around the post, that is the area that is visible at the top of the post in the cabin.

Again, note the inconsistency of the bedding compound. I'm sure that the Florida Sun had some impact upon the compound, I'll use Butyl when putting this all back together.

With the mast post totally removed, it's clear why we had the dribble! This whole area is dry, the boat has been under tarp for a couple of months.

Cleaning will be with a sharp blade to remove the compound. Goof Off to clean up.

Made a lot of progress in the clean up so far. Still a bit of the compound to remove, but some of the original work marks are below the surface and I'm not prepared to sand down below the general surface level. So I'll clean them as best I can.

Clean up complete. If this were going to be visible, I would repair the gelcoat. It will be well sealed.

I taped it off so that I could use 1,000 grit wet n dry to smooth the area. The curved marks appear to be made during the manufacturing.

Now that the area is smooth, I'll counter sink the screw holes and the post hole so there is a good seal with the Butyl.

Now for the Inside.

This pic shows the base plate mounted on top of the centerboard casing that fits inside the open end of the compression post base.

Notice how it's half full of water! Go figure! I have to assume it's from condensation or capillary action when the dribble ran down the outside of the compression post.

As the coffee table can only be removed when the mast post is raised, I took a look at the underside. Just remove the two screws holding it to the casing.

The compression post base plate is held in place with 4 SS screws, it looks pretty rugly around the base and at the top of the centerboard casing.

You can see our Stereo speakers mounted here. The sound is terrific when the table is in place. We can route the TV sound to them for a real studio effect.

After cleaning up the area with Goof Off (and opening the forward cabin hatch to vent the fumes!) and a few minutes with 1,000 grit wet and dry, the centerboard casing top looks much better and the compression post base cleaned up really good.

A few more minutes with 3M Stainless Steel cleaner and the base looks like new.

I'll use Butyl to bed the base plate back to the casing as the underside of the base plate is not exactly flat.

A little more cleaning to do around the screw holes in the casing.

Moving on to the Compression post and Mast base.

Looking at the underside of the mast base (the compression post is pointing up in this pic), it's obvious why we had the dribbles. I had not cleaned the underside of the base plate before taking this pick. The original compound was just not doing the job!

A few minutes scraping off the small patches of sealing compound and a few more buffing the base and post with 3M Stainless cleaner, the post looks great!

Done for the day, need to get a few supplies before putting it all back together.

Ok, so nearly done for the day :) Sanded down the coffee table and used wood filler to fix the two dings, has to be a temporary fix as I really need to replace the table. It's kinda useless as it is, size, height, etc. But the project is on a schedule for our trip on May 11th. So for now I'll just put a couple of coats of poly on it and replace it so that the compression post can be reinstalled. The poly finish is satin, and I must admit, that even though the color of the table top consistency is really yuk, the finish looks good, looks similar to the teak in the boat. So when I do put in the new coffee table, think I'll stick with that finish.

Now, done for the day.

Tuesday April 24th. Putting it back together

The poly coats on the coffee table have had 48 hours to dry out, I really like the finish (but not the color/shading consistency) but as mentioned, I'll replace the coffee table before the summer with something more useful.

So,

Butyl compound under the compression post base plate and screwed down. Done
Coffee table replaced and screwed down. Done
Countersink the holes under the mast plate for the screws and the compression post. Done
Replace the compression post. Done
Secure the base bolts and nuts (with new washers rather then reuse the rugly ones) Done

All done bar the clean up.