New Mast Step

Old Mast

The original LF38 mast step.

Here is a photo of the old mast step.  I knew from the get go that I had to unstep the mast and replace the step.  From what I have read this is a common problem with most LF38s.  The failing in C&C construction is that the center of the base was not well supported under the step.  The step rested on marine plywood, and over time wet plywood rotted away allowing the force of mast to push down and break the step.

Designing a New Mast Step

I looked into having a new mast step welded up from Aluminum angle stock like others have done. But I was told that it may be easier to have the mast step milled out of a solid block of Aluminum.  The idea was that while material cost would be higher, CNC milling is virtually labor free whereas welding is much more labor intensive.  Yes, much of the material is cut out, but it gets recycled.

Below is drawing from the 3D model of the mast step used to generate the CNC step file.  The mast step was milled the same day I dropped off the material.

CAD drawing of new mast step.

A solid block of 6061 grade Aluminum
formed the beginnings of the new mast step.

Mast step after CNC machining.

New mast step next to old broken step.

Mast step painted with several coats of epoxy paint.

Repairing the mast step support

1/2" structural fiberglass (FRP) board was used
to replace rotted plywood support.

Additional 1/4" FRP was added to build up
the support base before adding thickened
epoxy and leveling with the mast step.

Mast Step Installation with Coin

When I unstepped the mast I found a coin in the mast step. The coin was a 1976 U.S. Bicentennial dollar coin.  The practice of putting a coin under the mast has its roots in Greek mythology.  The theory goes that coins were placed there to pay the ferryman, Charon his fee for taking the departed across the River Styx to the afterlife should the vessel be lost.  While I'm not superstitious, I do like a good yarn, so I cleaned up the coin, stuck it down with a little sealant to the mast step.  Let's hope it's never needed.

Mast step installed with Bicentennial dollar coin just forward of the feel bolt.

New Thru-hulls and Seacocks

Old Thru-hulls & Seacocks

When I purchased the Johanna Rose, I had to transport this engineless vessel over 130 NM home to my marina.   I did not dare touch any of these seacocks for fear of disaster.  once hauled out of the water, I was glad to first remove the old thru-hulls, decaying seacocks, and cheap hose which were used for under the waterline scupper drains(see photos).

A concern with with any cored hull boat is water intruding into the core and leading ultimately to delamination.   The Johanna Rose exhibited no signs of wet core as she tapped out solid all around, had no signs of blistering (other than over the lead keel, see post on bottom work), and did not weep during the many months on the the hard.  But the first real concern and test was in removing the old thru-hulls.   Old leaky thru-hulls have been know to cause wet core problems.  On the LF38, which is cored with end grained balsa ever where except for regions where thru-hulls are located.   In this area the core is marine grade plywood.   the Johanna Rose has 8 under water thru-hulls: 2 in the galley, 3 in the head, and 3 in the engine well.  I removed all thru-hulls with a tool I borrowed from the marina.   Upon inspection of the inner core, I found no wetness or indications that thru-hulls were leaking.  This was a great news.  

removing old thru-hull

a close up view of the engine water intake seacock
& port scupper seacock

old seacocks in the engine well, notice the quality hose 

  

NEW Thru-hulls & Seacocks

• thru-hulls  
• (2)    3/4”    Groco FTH-750 
• (1)    3/4”    Groco TH-750 
• (3)    1-1/2” Groco FTH-1500
• (2)    3/4"     Groco THXL-750-W  

• seacocks 
• (5)     3/4”     Groco FBV-750 
• (3)     1-1/2”  Groco FBV-1500

Reaming Back the Core and Filling with Thickened Epoxy

The plywood core was reamed back from the thru-hull hole using a Dremel and a sanding drum following the procedure illustrated by Wally Bryant on the Stella Blue site.  The seacock boltholes were over drilled to expose clean fiberglass.  A coat of Johnson Paste Wax was applied to a thru-hull so that a thru-hull inserted into curing epoxy would release easily.  These thru-hulls were inserted with thickened epoxy to fill the inner reamed out area and a proper faired flush mount fit.  The reamed out area and the boltholes were first wetted with epoxy before being generously filled with epoxy thickened with colloidal silica.  

thru-hull in galley near keel stub

The Installation

The seacocks are mounted to backing plates made from a 1/2" sheet of structural fiberglass (FRP).  These FRP mounting plates are first aligned using a tightened thru-hull, marked, and then epoxied to the hull after grinding a clean surface.   The hull and backing plates are first coated with wet epoxy and then coated with epoxy thicken with colloidal silica  and finishing with a fillet of thickened epoxy along the backing plate circumference.  Care was taken so that epoxy would not interfere with the seacocks threads, but just to get certain, a tightened waxed thru-hull remained in place while the epoxy cured.     Prior to final installation, the thru-hulls were removed, soaked in Naphtha to dissolve the wax.   With the seacocks firmly epoxied to the hull, the thru-hulls were installed using plenty of adhesive/sealant.  after which the area is cleaned, sanded, and lightly faired with thickened epoxy.


  Seacocks

engine well seacocks 

new seacocks in the head

new seacocks under the galley sink

Thru-hulls

port scupper thru-hull and engine intake thru-hull 

starboard scupper thru-hull

head thru-hulls

head thru-hulls after first barrier coat