Saturday, 12 May 2012

A small bow thruster problem

The correct size 12v bow thruster had arrived (6kw/8hp) so Andy “invited” me to drill the holes in the tube.  There are three main parts to the unit.  A baseplate contoured to fit the 185mm tube; the electric motor; and the propeller shaft and gearbox.  He also showed me the installation instructions which included a paper cutting template for the three holes required to mount the bow thruster on the tube.

I carefully selected the correct drill bits and then drew a horizontal line on top of the tube.  Next I place the mounting block and electric motor on the tube and adjusted them, ensuring there was adequate clearance all around the unit.  The mounting block and motor were removed and I marked the location of the three holes using the supplied paper cutting template.

The two 9mm holes for the mounting bolts were drilled first.  Then I started on the 30mm hole for the gearbox shaft using a cone drill (this bit gradually increases the diameter of the hole).  Halfway through drilling the 30mm hole I realised the final hole would almost overlap the 9mm mounting holes.  This wasn’t shown on the cutting template so I stopped drilling.  The holes I’d drilled did match the cutting template so I them placed the mounting block back on top of the tube AND THE HOLES DIDN’T MATCH.   After physically measuring the supplied paper cutting template it’s NOT TO SCALE.  Why the hell would you supply a cutting template that wasn’t to scale??????

We now have a problem because the existing two smaller 9mm hole overlap with the location of the required mounting holes.  Consequentially it’s going to be a difficult task re-drilling the new holes.  However I already have a solution.  Andy can do it!!! Smile

Richard and James have been working on the stove hearth and display cabinet.  The drawer underneath the stove is now complete.  We will probably use it to store bit & pieces for the stove maintenance.

They have now moved onto the display cabinet and have fitted both vertical sides.

Richard has already made the fixed three timber shelves.  There will be two at the top and one approximately 16” above the floor.  These will have timber cupboard doors.  The remainder of the unit will consist of adjustable glass shelving and a hinged glass door.

Meanwhile I had completed the plumbing connections on the rear bulkhead.

The gas hole goes directly from the cabin to the gas locker avoiding the engine compartment. I will install the brass bulkhead fitting in the hole tomorrow.  The gas pipe will pass through the fitting to the regulator.  This will mean the gas pipe will run inside the hose and have no joints between the regulator and the oven/hob.

The final job for the day was to drill the ¾” hole for the shower waste fitting.  All the steel burrs were filed off the edges of the hole and construction adhesive smeared on the brass fitting before Jan and I worked as a team (me inside & her outside) tightening it all up.

White spirits cleaned off the excess adhesive.  It should be well clear of the waterline (I hope!).

Tomorrows tasks include marking out the location of the bow thruster batteries.  I’d like to fit them above the bow thruster motor thereby freeing up the remaining room in the locker.  The other task is to cut out some holes for the various controls.

Time permitting, the pump out and rinse holes for the blackwater tank might also be cut out.

The unfortunate news is the boatyard’s new inflatable paint shelter will not stay erect.  All the air keeps going to the bottom!  Apparently it will be going back to the manufacture to have the defects rectified.

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