RUDDER BARRIER COAT & FAIRING

Last weekend was spent applying coats of barrier coat (Interlux 2000e) to the rudder.  I decided to spray the barrier coat so that I had a bit better control over the thickness of the barrier coat.  And what is absolutely necessary for spraying barrier coat on a 70 lb. rudder?  A ten ton overhead crane, of course.

Maybe a bit overkill.

I applied about five relatively heavy coats of barrier coat and let them cure out for about four days.  Once they had cured out, the rudder was sanded with a long board again.  For a long board, I used a piece of 3/4" plywood and 100 grit sand paper.

I have a couple of 3M long boards, but they all seem to have a bit of a curve to them, so they do not work well for sanding on a flat plane.

The rudder was long boarded in the long direction working from the back to the front of the rudder and vice-versa.  Once I was satisfied with the flatness in the long direction, I used a shorter board to sand in the other direction and smooth out any flat spots that might have developed with sanding in the long direction.  The shorter board was about 16" in length and made out of a piece of 1/4" masonite so that it could flex to the curve of the rudder.

There were certainly some high and low spots that showed up.  Here is a picture just after I started sanding.  You can see the lighter spots that sanded out first.

Much of the barrier coat was sanded away in various places by the time I was done sanding and a few areas needed minor filling.  After the sanding was completed, I used a filler to fill a few low spots.   The low spots were not significant.  Here is a picture after sanding and filling.

I'm now ready for the final coats of barrier coat, which were applied yesterday.  More on that later.

RUDDER FAIRING & MOUNTING

The rudder is getting closer to completion.  I completed a good portion of the fairing by setting a few stations on each side of the rudder that could be filled between.  The stations were set by spreading a line of filler, covering the filler with a sheet of plastic, and then pressing my template into the filler.

The plastic was removed after the filler cured and then the excess filler was ground down to flush with the profile made by the template.  From there, filler was troweled on and struck off with a straight edge between the stations.  This was then long boarded with 36 grit sand paper in the long direction of the rudder and then finished off with a shorter more flexible board in the short direction of the rudder.  This process took a few steps of filling and sanding to get to a relatively fair surface.

Then it was on to mounting the rudder.  To complete this, I installed the gudgeons on the transom, set up a table beneath the transom to stand the rudder on, then tipped the rudder up into the gudgeons, temporary tying the rudder off to the boat at the top of the rudder.  From the J/30 specifications, I was able to determine the correct mounting height of the rudder.  The rudder was shimmed off of the table to get to the correct height.

Once the rudder was positioned correctly, I drilled out one of the mounting holes through the rudder for which the lower gudgeon is attached.  A bolt was run through this hole to keep the gudgeon in position while a 2nd mounting hole was drilled.  Prior to drilling the 2nd mounting hole the gudgeon was positioned so that alignment between the gudgeon and the pintle were correct.

With the lower gudgeon mounted with two fasteners, I moved to the top gudgeon using the same process as the lower gudgeon.  Once each gudgeon had two fasteners securely installed, I drilled out the remaining mounting holes and installed the needed fasteners.

While drilling out the holes in the rudder, I started with a very small drill bit and drilled through from each side of the rudder.  From there, I slowly stepped up the bit size, drilling 1/2 way through the rudder each time I stepped up in bit size.  The purpose of this was to ensure alignment of the holes from one side of the rudder to the other.

After the rudder was mounted, I drilled a hole at the top of the rudder for which the tiller mounts to.  I made a slight error in the location of this hole which resulted in the tiller not being able to tip up.  This problem was remedied by sanding down a small portion of the top of the rudder to allow for clearance when the tiller is tipped up.

Here is a picture of the rudder after being mounted on the boat.  You can see the table below the rudder that was used to hold it temporarily in position.