Wednesday, June 3, 2015

Major Overhaul 2015 Part 1

Just what is a major overhaul/refit?  I'm not sure.  Is it over X dollars spent?  How about the number of tasks completed?  I asked a buddy and he did not know the answer, but suggested Strider's winter 2015 projects fit his definition:  "I know it when I see it."  So, a major overhaul/refit for Strider in winter/spring 2015.  It all began with fiberglass fatigue/failure on the amas, which kept leading to more...naturally.



Strider is folded most of the time.   Folding creates a long lever between the ama and the forward aka with the force focused on the pivot pin.  Wind and waves combine to force a scissoring action between the two, fatiguing the ama fiberglass.  After several years and possible previous repairs, the ama fiberglass was collapsing.
Port Ama Extended
Starboard Ama Folded
New fiberglass repair area
Area Repaired.  Black UHMW was selected for the rub rail/skid plate for its alleged UV resistance
In addition to the external repairs, additional support was added inside.  OEM included an athwart support, centered on the pivot bolt.  This did fine supporting the structure while extended, but did nothing while folded.  There is now an additional fore and aft support (fiberglass with wood core), reinforcing the structure while folded.

Internal Reinforcement

Simple scissor preventer.  Eye nut on top, 3/16 dyneema with snap shackle in the middle and a U bolt on the ama.  Tails at the top are for adjusting the length.

Solar Panels

I've made mention in previous posts I was not satisfied with the 100 watt solar panel placement.  Too far aft and partially shaded by the stays and the net.  So, moved them forward, just aft of the ama hatch.  This move necessitated the repair of the bolt holes, which were completed with a bit of fiberglass.  But since the non-skid color could not matched, the grey, gelcoat non-skid was sanded off and new, off-white, polyurethane/bead non-skid applied.  Only the exposed ama top, aft of the panel, got the non-skid.  The area under the solar panel is plain off-white polyurethane.

To move the solar panel forward, a folding padeye, mounted 6 inches aft of the hatch for the ama in-haul line, had to be removed.  This roller's axle was replaced with a bolt and eye nut for the in-haul line.



Were out of round at the pins allowing the ama/akas to flex while underway.  It is a bit disconcerting to see them flapping around in the waves.  So, the hinges were removed and brought to a machinist who has fabricated seemingly massive collars/bushings to bring the hinges back into round.

Note the large bushing.  It was pressed in and then welded.
Forward half installed.
Aka half installed.


With the amas off and the hinges removed, the shoulder cracks on the vaka were more visible and and more extensive.
Forward Starboard
Aft Starboard

Swing Wing Cables

These cables are inside the aft aka and used to extend the amas, pulling the ama forward via a line integrated in the net.  A couple broken strands were found on a cable indicating replacement is due.  So, removed, cleaned and polished the brass aka sheaves abraded by the stainless cables.  Used a rubber drum for a sanding wheel chucked in a drill press.  Clamped the sheave assembly in a vise and pressed the sheave onto the rubber drum, causing the sheave to spin.  Used stiff sand paper to smooth and polish the sheave.  Then, replaced the stainless steel cables with 1/4 inch amsteel using heavy duty thimbles.

1/4" dyneema aka cable with red 3/16" dyneema soft shackle.


With the ama off, was able to inspect the waterstays, the cable preventing the amas from collapsing upward while in the extended position.  The waterstays were about 7ft of 14mm stainless cable with a 20mm stud terminal at one end and an eye terminal at the other.  One eye terminal had extensive cracks.  With one close to failure combined with the manufacturer's recommendation to replace all every 5yrs, I decided to replace all.
I contacted the manufacturer and was quoted about $2200 to replace all, but the material was not in stock, would have ordered, then manufactured, then shipped.  I decided to attempt something new with a local rigger and machinist.
We were able to salvage the 3/4" double jaw toggles from the hull side end and the 20mm stud terminal from the aka side.  Had a machinist bore out the cable from the 20mm stud and tap the stud for 5/8in-18 T-bolt toggle, like the bottom half of the turnbuckle in this picture.

Salvaged 20mm stud with new 5/8in t-bolt with terminals
Locally fabricated 1/2in Cortland Plasma 12 strand synthetic line is used along with thimbles to replace the cables.  Weight reduction is 28 pounds.  Material cost was about $500.  Machining was $300.  Labor, including consultations and learning how to assemble the system (watching the rigger splice and sew) was $600.  $1400 for new waterstays and done using local talent and material!
New Waterstay Assembly
UPDATE:  This did not work out as planned.  The combination 20mm stud and the 5/8 t-bolt toggle was too long and interfered with the ama folding.  Fortunately, Plan B was too use the 5/8 t-bolt toggle solo, inserted into the 20mm receptacle.  Eliminating the 20mm stud also removed 5 pounds.

The results:  Purple is the plasma, blue is 1/4" dyneema lashing.


Replaced the silicon sealed 1/4" plexiglass with weather stripped 1/8" polycarbonate.  The thin polycarbonate was relatively easy to work with.  The difficult part was removing all the old, black silicon sealant.
New Windscreen

Rudder Assembly

Removed/cleaned and replaced the bottom fitting, bottom half of the rudder support assembly.  Assembly was sloppy in its holes, with about a 1/2 inch swing.  So, created a couple stainless bushings by modifying spacers to fit over the assembly bolts and redrilled the fiberglass hull holes to fit the outside diameter of the spacers, now a very tight fit.  Used butyl tape with countersink method detailed in this Compass Marine article.

Replaced a couple aluminum, 75mm, ball bearing Frederiksen sheaves, worn through by the stainless steel steering cable with a couple 50mm Ronstan RF50000HL sheaves.  Though slightly smaller, the sheave is a direct replacement and the Nylatron material is good for cable.

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