ABT TRAC Captains & Owners Class

The hydraulics' system is one of the most important operational systems on the 63.  The stabilizers, bow thruster, stern thruster, windlass and davit (i.e., crane on the boat deck) are all powered by hydraulics.   Except for the davit, all of the others are tied to ABT TRAC equipment. 

Given my limited knowledge of hydraulics I thought it would be worthwhile to take advantage of ABT's generous offer to the owners present at Outer Reef's Rendezvous in Charleston last June to attend their 2 day Captains and Owners class in Rohnert Park (Sonoma Valley) California.

The class taught by Eric Folkestad proved to be extremely valuable.  We learned hydraulics' theory, operation, maintenance and basic repairs.  We also received a very detailed tour of the manufacturing facility where we saw parts being machines and systems being assembled.  You come away from the tour with the sense that ABT builds a high quality products.

Standing at ABT's "Wall of Shame" in clothes that might get dirty

The class was comprised, as advertised, of both captains and owners.  The participants represented yachts ranged in size from a Nordhavn 43 to a Selene 92.  Three of the owners were, like myself, in the build process.  Of the twelve four of us were Outer Reef owners (my 63 and three 65s).  My seat neighbor to my right, Randy, owned a 68 Nordhavn and was getting ready to cross the pacific.  To my left was the captain of a Johnson 87 based in Puerto Rico.  The participants were both very knowledgeable yachtsman and highly motivated to learn more about hydraulics.

ABT takes this class very seriously and has invested time and equipment to build a classroom with an operating hydraulics system.  This allows the instructor to demonstrate operation of all components and to simulate failures.  They call it their "Wall of Shame."  I think it should be renamed "Wall of Pride" as they are going out of their way to help us understand what can go wrong and what to do about it.

Operating wall of hydraulics equipment

A pair of operational stabilizer actuators tied to the equipment in the above photo

The second part of the tour focused on TRAC's fiberglass shop where they manufacture the stabilizer fins.  Here we got to see the process of fiberglass lay-up using the vacuum bag technique along with assembly of the fins.  It was most instructive for me as up until now I had never observed the vacuum bag lay-up process.  Reading about it is not the same as watching the process live.

Explanatory Note: Multiple layers of fiberglass cloth are place in the mold.  Then hollow plastic tubes with holes to distribute resin are placed about 6 inches apart.  A plastic bag is layered on top of the mold and the air is sucked out creating a vacuum that presses the cloth to the mold.  The resin is then mixed and placed at the mold.  A tube is placed in the resin,  When the clamp is released the resin flows through the holes in the tubes and then evenly into the fiberglass cloth creating the reinforced fiberglass.

TRAC Stabilizer Servo box - The system's brains (literally a computer)

ABT Thruster Control Box

A bit more explanation.  Why hydraulics?  The answer is that hydraulics have the ability to apply significant force using oil under pressure.  The basic rule of thumb is that pumping 1 gallon per minute at 1500 PSI equals 1 horsepower.  Pump 30 GPM at 1500 PSI and you get 30 HP.  This enables the bow and stern thrusters to propel the boat in the desired direction and the stabilizers to exert sufficient force to correct roll in heavy sea on a boat like the 63 displacing 73,000 lbs.  Incidentally, the thrusters operate at 3000 PSI.

Hydraulic bow thrusters can operate continuously, which is there advantage over electric thruster, which stop working when the motor overheats triggering a circuit breaker. This can occur in less than a minute of heavy thrusting.  Unfortunately, heavy thrusting is when you want to be confident that the thruster will not abruptly stop.  That's the good news.  The bad news is the hydraulic thrusters are more expensive and more complex. 

Hydraulic system are also very reliable.  We had a hydraulic swim platform on the 48 Sundancer.  from 2006 to 2012.  That platform lifted an 800 pound Caribe RIB with a 30HP engine reliably for 7 seasons.

When I look at the notes I took and the "to do" lists I created it is clear that ABT imparted significant and practical wisdom.  Here some examples

• Stabilizer Alarms: First alarm occurs at 160 degrees Fahrenheit.  Slow down and check for cause of overeating.  Second alarm at 180 degrees requires engine shut down.  Note: Hydraulic pumps work continuously from a PTO on the engine.  They cannot be shut off.
• Hydraulic system requires an alternative cooling source if the raw water cooling pump fails. 
• Annual check: Dip into the oil reservoir and place a drop on a piece of paper.  Date and store the sample.  Check for changes in color from year to year.
• Ensure stabilizer fin drain holes are not blocked.  Fins will explode when exposed to heat when the boat is on the hard if the fin drain holes are blocked.
• Thruster props must be checked by the diver during monthly bottom cleaning and cleaned on boat sides.
• Props can be removed in the water
• Props must be replaced on the side it was removed from.
• Place a white mark at hydraulic line crimps.  Then visually check that the mark has not moved to verify fitting integrity
• Get stabilizer parameter list ad store in servo box. The system has 334 specific parameter that enable the computer to operate the stabilizers.  ABT commissioning personnel start with 334 factory standards and then custom program each system.  The customized settings are recorded on the parameter list. The owner can change the parameters with the help of ABT personnel remotely when fine tuning is required. 

Everything about ABT was first class including lunches and the wine party at the end of the class

Written by Les.