Category: How To

Susan, our 1940 16’, Cypress Lyman Yacht Tender’s bottom has reached a critical milestone. Reconstruction followed deconstruction that included releasing the keel, garboards and keelson was followed by fabricating and installing a new keelson.

As of this morning everything is back in place. The keelson and keel were installed bedded in 3M5200. The garboards were secured to the keelson using #6 x 1” Frearson head silicon bronze wood screws. 3M5200 was applied to the seams formed where the garboards and first strakes meet. Then RJ and I, happily with RJ running the clenching iron inside the hull, clenched the seams from transom to bow.

The bottom was faired using four applications of 3M Marine Premium Filler and sanded between coats. John hand sanded all of the strakes, garboards, keel, gripe and stem by hand until the bottom was absolutely fair.

We then applied the fourth coat of Clear Penetrating Epoxy Sealer from the waterline down. Why so much? Three coats were applied ahead of the Marine Premium Filler, but with everything sanded between coats, applying the fourth coat post-fairing buys additional insurance against water absorption and accumulation attacking paint adhesion and thereby facilitating rot.

From the Smith’s Web site: (CPES) creates a tough, flexible resin system that moves with the wood. It allows the wood to “breathe” so excess moisture does not accumulate behind it, promoting paint-failure and ultimately rot.

We then caulked all of the seams, those where two strakes meet, along the garboard-keel seam and that between the strake tails and the transom.

Milestone reached, Susan is poised for priming, and in our case the primer of choice is Interlux Interprotect 2000E Two-Part Epoxy, five coats of which will be applied over the next two days. Once we reach the target film thickness of 10 mils, Susan’s bottom will be protected against water absorption and it will be time to apply her bottom paint. (Since she will most likely be trailer or lift sailed, we may opt for Pettit Hard Racing Copper Bronze bottom paint in place of the traditional Sandusky Lyman Copper Bronze Antifouling paint, since the latter is designed for vessels that live in the water.)

Our 1940 16’ Lyman Yacht Tender’s spine transplant is complete, and the patient is doing quite well. The new keelson and the keel’s underside received three applications of Clear Penetrating Epoxy Sealer (CPES). Following Danenberg, who insists that doing so delivers deeper penetration and more thorough sealing, the second coat was applied immediately following the first coat. The third coat was applied twenty-four hours later.

After fitting the keelson and keel to the boat and each other, and sinking a series of temporary position-holding screws through the keelson and into the keel, John bored the rudder and prop shaft bores. He also drilled the holes for the machine-threaded bolts that will secure the lifting ring, yes it is fixed to the keel/keelson and shaft log.

Confident that we could reassemble the pair and still have them matching, we separated them and frosted the mating surfaces with white 3M5200. (White is much less expensive than mahogany 5200 and delivers the same bonding strength. Since the bottom will be primed and painted, spending the extra that mahogany 5200 costs is just wasting money. However, be patient with the white as it takes as much as fifty percent longer to set up than the mahogany.)

After reassembling the now monolith-to-be and driving screws through the keelson into the keel, we installed it on ribs bedded with mahogany 5200. (Any squeeze out here will be visible in the bilge. Even though it will be thoroughly protected with Sandusky Paint Company Lyman sand tan bilge paint, we do not want to risk that a scuff or scrape exposes white 5200 beneath the paint.

John has also completed his knee semi-transplant, a truly complicated Dutchman, as well as fashioning Dutchman repairs to the forward end of the gripe. Once everything is sanded in and sealed with CPES, the bow will be ready for primer.

We will focus on installing both garboards, which will also be bedded in white 5200, over the next several hours, followed by securing the aft tails of the bottom strakes to the transom.

Then Michael “gets” to spend the rest of today and this weekend applying and sanding 3M Premium Marine Filler fairing compound to the countersinks. After a final application of CPES to the entire bottom, and caulking the strake-to-strake seams with 5200, Susan’s bottom will be ready for priming and painting.

Maybe next week?

John has fabricated and is now focused on installing the 1940 Lyman Yacht Tender’s new keelson. One hint if/when it is your turn to do so. Since the keel, and the keelson are bowed, they must be joined on the hull. While the difference in radii may appear small, there is a difference that will keep the rudder shaft, prop port and other components from lining up if the bores and fastener pilot holes are drilled and fasteners are driven in while the assembly sits on flat surfaces like work tables or saw horses.

John and I first positioned the keelson correctly along the ribs’ lower extremities and drove a half dozen or so temporary screws through the ribs and into the keelson. We then laid the keel in place, clamped everything together and drove position-holding screws through the keelson and into the keel.

Only then were we able to bore rudder shaft and other ports through the new keelson. We then removed the temporary screws passing through the ribs and into the keelson, which released the entire assembly.

It will be separated, receive a final application of CPES and then the keel and the keelson will be joined, yes, again on the hull, with a generous layer of 5200 “frosting” troweled on between the two planks.

Installing the garboards completes the replacement process, but cannot happen until all remnants of the old clench nails are removed.

We will finish fairing her below the waterline and John will complete the work needed on her stem and knee, and it will be time for Interlux PreKote primer.

Three coats of Sandusky Paint Company (SANPACO) Lyman Copper Bronze Antifouling paint

That we learn every day and with every boat we lays hands on makes wood boat conservation incredibly enriching.

Our 1940 16’ Lyman Yacht Tender, “Susan” has been our latest teacher since RJ and I began setting the below-waterline clench and rivet nails last Friday. (That RJ offered to “drive” the clenching iron while I popped each nail head with a bunch and dead blow hammer was a huge plus for me.)

We began at the waterline and worked strake-by-strake towards the keel. It was then that Mr. Murphy’s reared his ugly head. “Hey! We have a problem! I can see lots and lots of light coming through between the garboard and keel. It looks like the keelson is broken and split.”

Next came backing out what must be one hundred or so screws and then cutting through all of the starboard garboard’s clench and rivet nails. Yes the very ones we had just so carefully tightened!

Out came the garboard, exposing the garboard’s, formerly chamfered starboard edge, or in about forty percent of it, what was left of same.

Sure. We could rip that chamfered edge off wherever it had failed and fit pieces in place. Then, using many tubes of 3M5200 and lots of bilge paint on the other side, we could have hidden our “repair.” It might have even held for a while, but unlikely longer than a season or two at most. Releasing and installing a newly fabricated, white oak keelson is the correct solution, and for us the only one we will put our names on.

So, with the port garboard having joined its starboard counterpart on a wall rack several hours later, it was time to release the keel and keelson.

I believe you will agree that, having viewed what we released in the clip, consigning the original, now 78 year old, keelson to the scrap pile is the best path forward.