Final Sea Trials

(Updated 9-20-2021)

 

--Minimus II, Description

--Building Minimus II

--First Sea Trials, July 2020

--Second Sea Trials, September 2020

--Further Sailing Notes

--Back to Adventure Page

 

We made a few upgrades to Minimus II this summer and in September trailered her to the Oregon coast for final sea trails.  Among the upgrades were a solar electric system, a centerboard to help her come about when tacking, a stove upgrade, oars to replace the SUP type paddles and .  We were quite pleased with how they all worked.  Below are descriptions of each.  

 

Solar electric system:
We installed two AcoPower 12V, 30W monocrystalline solar panels on each foredeck.  The panels charge a 12V, 24Ahr LiPo battery by reBel Batteries.  We purchased the LiPo battery mostly to save weight, but have been impressed with its performance.  The charge controller is a PWM type, but will be replaced by an MPPT type before voyaging for more efficient charging.  12V is used for the running lights, AIS and compass light.  Tablet, phones and InReach are charged via two 12V to 5V buck converters.  Each hull has a converter located amidship with four 5V outlets. We used buck converters as they're more efficient than the more common converters that plug into a cigarette lighter socket. 

Although the system is small, and the weather was partly cloudy, it had more than enough power to keep phones and tablet charged as well as AIS and LED running lights.

 

Centerboard:
As noted in our first sea trials report, the boat had difficulty coming about when tacking.  This was due to the hull shape, which was designed for good tracking while at sea.  To solve this, we added a centerboard to provide more of a pivot point to encourage reliable tacking.  It worked amazingly well.  We spent a day offshore, mostly sailing to windward in light air and didn't miss a single tack.  The board takes just a couple minutes to install.  

We don't expect to use the board much while voyaging, but it's good to know it's available when tacking is necessary.


The centerboard passes through a slot in the center deck board and is supported laterally
by two dyneema retaining lines on each side.   The board is 6' 8" long by 13" wide and 1" thick.  
 


The board is lowered into the slot until the two 3/4" diameter holes in the board
are just above the deck.

Two 1/4" dyneema lines are permanently attached to the middle and forward
main beams and pass up through the slot.  These lines are fed through the
two holes in the board and up to chocks at the top of the board.

Here, the two lines from the side of the boat Pearl is standing on are
fed through the centerboard holes and up to the chocks.

All four retaining lines are now in place.

The lines are fed through slots at the top of the board and secured as
shown here and in the next photo.  The board is then lowered into place.
 

Another view of the chocks for securing the lines. 

Board is ready to be secured. When sailing, there's quite a bit of upward
thrust on the board.  This is counteracted by a retaining board shown
in the next few photos.

The retaining board is secured by passing a loop of line over its forward end. 
The loop goes around one of the support beams under the deck boards.
 

The forward end of the retaining board is pressed down and secured
with a loop of line at its aft end.

The board is now ready for sailing. 

Side view of retaining board.

The four dyneema retaining lines can be seen going from the board up
to where they're secured to the center and forward main beams.  
 

 

Oars:
We originally used two SUP type paddles for auxiliary propulsion.  Wishing for a bit more power, we replaced them with two 12' 6" oars and oarlocks.  The oar looms were made from 1-1/2 x 1-1/2" x 10' clear fir boards with blades made from of 3/4" x 5-1/2" x 4' cedar boards.  The oarlocks were experimental, but have worked better than any we've tried on other boats before.  As with the centerboard description, the photos and captions below will hopefully explain it. 

Here's a link to a video of the oar and oarlock in use: https://youtu.be/OfUTg-0nKd4

 


Oar in oarlock.  Oarlocks are bolted to port and starboard cabin tops.  

Base of oarlock is made from a piece of aluminum plate 3/8" thick
by 4" x 6".  Plate is through-bolted to cabin top, backed by a piece of 1/2"
plywood inside the cabin. 

The pivot for the oar is a 1/2" x 8" stainless steel bolt secured to the aluminum
 base with nuts and washers.  A piece of 1/2" PVC pipe over the bolt freely
rotates around the bolt.  The 1/4" dyneema line keeps the oar in place on
the pipe and the white retaining line prevents the oar from sliding downward.

As the oar rotates while rowing, so does the PVC pipe, so the friction is
between the pipe and the bolt, not between the oar and the pipe.  The action
is very smooth and quiet.   
  

Another view of oarlock.  A loop spliced in the dyneema line goes over the bolt.
 

Closeup of oarlock.

 

Stove upgrade:
As we mentioned on the Second Sea Trials page, we're using a Gas One stove than runs on either butane or propane canisters.  The piezo electric igniter makes it very convenient to use.  For safety, extra butane cannisters can be safely stored on deck.  We've added a pot support assembly that gives more stability to the stove and provides adjustable pot supports.


Gas One stove with pot holder.

Pot holder without stove.  Base is made from 1/2" x 12" x 12" plywood.
 Four bolts in center secure stove to pot holder. 
Pot holders pivot around three bolts near edge of board.
In use, pot is placed on stove, then the three wing nuts are loosened, pot holders
are pivoted against pot and tightened.
For use on a multihull while sailing or on a monohull at anchor, it's a very secure setup. 
  

Underside of pot holder showing carriage bolt heads.  Rubber
pads at corners make the pot holder and stove assembly very
resistant to sliding on countertop. 

Detail of pivoting pot holder.  Bolt on left is a fully threaded 5/16" x 6" carriage bolt. 
Pivot arm is made from 1/8" x 1" x 4" aluminum bar stock.  Bolt on right is 1/4" x 3-1/2" hex head
machine bolt with head cut off.  

Stove mounted on pot holder and secured with four bolts.

Stove and pot holder assembly ready for use.
  

 Parachute sea anchor:  
One upgrade we didn't have an opportunity to test is a parachute sea anchor we made.  It's purpose is not so much for storm conditions as for holding position.  That can be handy when approaching a harbor at night and waiting for dawn to enter.  It's 7' in diameter and made from 4oz. nylon fabric. 

 
Pearl struggles to hold onto parachute sea anchor in wind.