Seeking the Zen of Sanding

 The last episode pioneered presenting the completed component first, followed by discussions of the details.  This led to no great out cries and may contribute to comprehension of my efforts.

You may recall from the last episode that crossbeam progress was limited by the epoxy and lumber supply.  Two of the four crossbeams were constructed up to a point requiring vast quantities of unavailable epoxy.  The lumber shortage remains, but the epoxy shortage does not.  We'll pick up beyond where we left off.

Mast Crossbeam

This 14' 9" mast crossbeam will be located just forward of the cockpit.  It is the longest and most complicated of all the beams.  It has been enveloped in fiberglass and hand sanded.  The mast step is located on the beam's top center.  The step distributes the mast compressive loads onto the beam structure.  A dolphin striker, not yet installed, counters these compressive loads on catamarans.  To either side are semi-circular access ports located near the points where the beam is lashed to the inboard hull sides.  These ports allow access to anchor points for high strength synthetic line to pass through a hole, in the beam underside, to a centered standoff (not installed) three inches below the beam.   The line then returns inside the beam to attach to the opposite side anchor.  Tension on the line distributes the mast compressive forces to the hull attachment points rather like an upside down suspension bridge.

If you look carefully at each end you will find a cleat.  These cleats will be used for bumpers, springer lines and a future cockpit tent.  

I learned late in the process that the beam work was much easier on the saw horses rather than the bench.  I could access all sides and roll it over as required while completing the endless sanding seated.

The first task is to complete the five full length fillets along the beam's length.  These fillets reinforce the bonds between the 3/4" plywood web and other components as well as providing a smooth transition for laying fiberglass.  Of course these five full length fillets will require sanding by hand before fiberglassing is possible.  Here the yellowish fillet is reinforced with a three inch wide strip of fiberglass along its' length.  The gussets and other beam interior surfaces have received the finial coat of epoxy before a fairing will cover these surfaces.  Beam areas epoxied to the fairing are sanded as well.

  

Cutting out a fairing requires a template.  A strip of 3/8" plywood spans half the fairing width and is wire tied through gusset holes, conforming it to the fairing curve.  Small sticks are hot glued to the plywood to define points along the fairing edges.

In the first attempt at this, I used a piece of limber lumber that distorted when the wire ties were tightened.  This resulted in a fairing half that did not fit and I have no material for a redo.  I was lucky to find it could be made to work on the other end with some extra labor.

The template is laid on the fairing material and marks are transferred from the stick ends onto the material.  Nails are driven into these marks and a batten is clamped to the nails.  The batten creates a smooth curve that a line is drawn against to define a cut line.  

Works like a champ!

The fairing is faired.  Notice the outlined area on the lower left beam's end.  This wedge shaped area is a sixth epoxy fillet running the entire length.  It may have taken a week to complete as only so much epoxy can be applied and still maintain its' shape until it sets.  Of course sanding is required before each epoxy application.  I considered using wedge shaped lumber to fill much of the void, but thought it would be too much of a juggling act as the wedge and fairing are best adhered at the same time.  The wedge idea will be revisited on the next beam.

A early image of the inspection port and cover for the dolphin striker anchor.  The anchor is a 3/8" stainless steel bolt passing through two and one half inches of lumber to an imbedded nut.  As with all fastener holes, the holes are drilled over size and then filled with a high density epoxy.  The filled hole is then drilled to fit the fastener.  This arrangement prevents a pathway for water to enter the wood as well as provides better bearing surfaces for through fasteners and threads.  The inspection ports and covers received epoxy filled fastener treatments for all six cover retainer screws.

The first post fiberglass sanding in progress.  Hand sanding produces troublesome callouses where the finger nail edge meets the flesh.  My callouses from sanding the hull were just beginning to sluff off when I again had to seek the zen of sanding in the beam construction.  The taped up fingers offer some protection, but are not the hot ticket.  One taped finger tip I've learned is to use the regular cream colored masking tape as it will not unravel like the shown blue painter's tape.  This may be the first post fiberglass sanding, but not the last before the beam is fully completed.

Aft Crossbeam

Surely, some may find endless amusement in my trials by sanding.  I must soldier on to achieve the goal of beach bars and bikinis for evermore.  To that end, the 14' 4" aft cockpit beam construction is well underway.  The full length epoxy fairing fillet will soon be ready for shaping by sanding.  The wooden wedge filler idea was abandoned as the available lumber would not permit me to keep my fingers while making the cuts.

Painted Hulls

Then there were two...  Epoxy primer and top side primer arrived on a recent shipment.  This enabled the application of top side paint and antifoul paint on the starboard hull.  It has been unusually cool for late spring and early one morning I was able to apply one coat of topside paint that would flow out to a smooth finish.  Additional coats will be necessary, but that will have to wait for cooler times.  

The hull was inverted for the painting process.  It is always a dicey process inverting or righting a hull.  The hull suspension/rotation lines are beginning to show signs of fraying.  I hope I have inverted the hulls for the last time, but this may mean that at some point I'll be lying on my back and reaching up to sand a hull.  Ugh, where is the zen in that?

Three Years In

This September marks three years since the boat materials arrived. Since then I have spent most everyday, in social isolation, working away making plywood sheets into the larger boat structure. The social isolation was good training for the Trump Flu that has put everyone in isolation.  As I trend high on the introvert scale, social isolation is not a hardship for me. 

Out of the 37 full sheets of plywood received, only six remain full sheets.  I'm on the last five epoxy gallons of the twenty estimated to complete the boat.  More materials are needed but current situations place obstacles in the path to obtain additional materials.  This does not yet impede progress as much remains to be done with the structures and materials on hand.

Above the starboard hull is hollywooded up with all the hatches and the solar powered ventilator/light fake installed.  Work easing the transitions between surfaces must be done before this hull is ready to receive fiberglass.

Chocolate brown epoxy fillets ease the surface transitions that the fiberglass must conform to.

Sanding and an application of the green fairing compound, followed by another sanding, completes the fillets.  

The bow and stern receive fillets.

A bit of sanding and the stern is ready for fiberglassing.

Forward and aft cabin ends (as well as the sides) received a roof line brow that protrudes 3/8 of an inch from the cabin surfaces.  The brow feature is copied from the larger Tiki 38 version.  The brow adds a shadow line that emphasizes the curving roof and echos the crossbeam curve that will be mounted on the deck below.  I think it gives the hull a very jaunty look.

This is the inboard side of the starboard hull with parts of the washboard closing up the companionway.  The cabin side slopes so that any water between the washboard and the cabin side can pool at the bottom.  It is difficult to see, but weep holes are made near the bottom corners to allow the water to drain away and help prevent rot.  Weep holes are also visible at the top on either side of the companionway opening.

 Above is a closeup of the forward weep hole at the top of the companionway opening.  Water can leak into the gap between the roof and the opening cover (shown moved to the right).  The roof slopes so that water will drain towards the cabin interior.  A rasp was used to create a sloping groove that will direct water down the cabin side rather than inside.  I more rasp work sloping will be required to assure this will work correctly.  Multiple fiberglass applications to these intricate surfaces will be necessary for  waterproofing.  

The bow and stern receive fiberglass in multiple applications.  The fiberglass is applied to the sides and the epoxy is allowed to cure.  The fiberglass is then trimmed and sanded to taper the edges.  The tapered edges help blend in the following fiberglass applications that cover the edges and other features.

The starboard deck, cabin and shear stringers now sport fiberglass protection.  Covering the shear stringers required fiberglass cut on the bias to conform to the shapes.  It was a hell of a time for my orbital sander to disintegrate, but I soldiered on; sanding by hand as much as needed to accept the next fiberglass application.  When it was all covered I was fortunate to locally source a new orbital sander.  My lesson with this was that it is better to sand the day after the fiberglass was applied than to delay and sand the fully hardened epoxy at a later time.

I've left the fiberglass to cover the aft port light and aft solar powered ventilator/light openings.  This should help to reduce the dust making its' way into the hull.  Much dust is sure to be generated in fairing (smoothing) the hull before painting.

I'm uncertain if I have enough epoxy to completely fiberglass one hull.  I also thought I could get a break from sanding (not the case when there is a boat to build) if I branched off into cutting out the three crossbeams that will tie the two hulls together.  Of course these beam components require two coats of epoxy followed by ..... sanding. 

Above are the main crossbeam plywood components at a length of 14 feet, 8 inches.  This gives an idea of the boat's width which seems very spacious to this former Hobie 16 skipper.  

The crossbeams will gain additional strength by timbers installed on the upper and lower surfaces.  In boat building, timber is a generic term for a piece of lumber.  I feel more like I'm building out of sticks and twigs rather than timbers.  The needed lumber is about a 1/2 hour drive away, but I am not able to travel that far.  My pickup blew out a brake line so that it was shooting brake fluid out the wheel well as the pedal went to the floor.  All the brake lines are held together by rust encrustations and must be replaced.  The upside is the brake line gave up just outside my gate.  The downside is I don't feel like fixing it and my mechanic wasn't working at last check.  I'm left with the pleasure of scooter rides for the time being and maybe regrets for selling my bicycle should the scooter also give up.