Roughing Out and Fitting the Dutchman Patches

     Good Friday allowed me to spend some time cutting out the dutchman patches from an 8/4 plank of mahogany, as well as some time on Rhino working to fit the patches.  The  process for roughing out the  dutchman patches was straight forward:  apply the dutchman template to the 8/4 mahogany plank, trace out the patch to be cut out, and then proceed to remove the patch using the bandsaw.   I intentionally left the dutchman patches oversized in order to trim the material on site, working toward a good, tight fit in the toerail.  

At the same time I roughed out the port and starboard material, I roughed out the small, 3" x 5" bow piece.  Total time spent in the shop was about an hour.

After roughing out the patches in the shop, I took a trip over Rhino to begin the fitting process.  The amount of material I left in place versus the actual measure of the void came in handy, as I decided to widen the void in some places in order to remove questionable wood within the toerail.  I used a combination of random orbital sander and a hand plane to shape the dutchman down to a tight fit.  Seen below, the port dutchman "working" its way into position.

The bow piece, shown below, was a much easier effort due to the simple form of the dutchman.  There is need for follow up on this piece, as I plan to set the patch a little deeper in the rail.  I will remove more material in the rail to allow a deeper set for the dutchman.

The port and bow pieces settling into their new homes.  More work is required to get the patches in place, and prior to beginning the staining, sealing, and numerous coats of varnish.

March 29th, 2013 - Total Time 4.5 hrs

Toerail Material Removal at Bow

     Continuing where I had left things on Friday evening, I spent the fleeting minutes leading into what would become a wet weekend by removing the worst of the water and sun damage at the most forward part of the toerail.  There were clear signs of water damage within this area marked for repair, and I worked to remove material until I reached unmarred material.  The cracking seen in the lower portion of  the picture will be filled with Interlux paste stain wood filler, sealed, and then varnished to match the balance of Rhino's toe and handrails.  The work day was cut short due to inclement weather settling in - see raindrops on the rail.

Another view of this bow section.  Again, the remaining checking will be filled in order to seal off and prepare for varnishing.

This 4" silicon-bronze screw shows clear signs of corrosion as a result of water ingress - this damage was brought on by the loss of the protective varnish.

March 23rd, 2013 - Total Time 1/2 hour

Starboard Material Removal

     Immediately following my office gig on Friday the 22nd of March, I arrived at Rhino for continued work on the removal of the starboard material subjected to water ingress.  I retrieved the starboard template stored in one of the aft lockers, and began to trace out the area to be removed. 

You can see that I seemed to have struggled aligning the starboard template for the eventual dutchman patch, yet in the end I prevailed.

After a couple hours of old-fashioned handy work, I had removed most of the questionable material from the starboard rail.  Like the port rail, there would be some fine tuning in order to have the dutchman seat properly in the prepared void.

The toerail is secured, in its length fore to aft, by  4" silicon-bronze flat head wood screws.  All six screws that I removed were showing signs of corrosion as a result of the water ingress. 

The overhead picture shows the material removed from the port and starboard rails, and in process of preparation to receive the dutchman patches.

Work area secured for an approaching week-long rain event.

March 22nd, 2013 - Total Time 2 hrs

Preparing Templates / Port Material Removal

     Since Rhino's toerails have a convex surface, and since I had plans to apply a router for the removal of the bad wood, I had to configure a way in which to safely remove the bad while preserving the good. I thought the best way to approach this task was through the creation of a template on which the router could operate, following a predetermined path.  To that end, I went ahead and scribed the convex surface of the toerails onto 6" x 8" sheets of 1/4" birch ply.  I prepared a forward and aft piece for the port toerail and also for the starboard toerail; taking these measures back to the shop, I carefully removed the material along the scribed lines.  The idea was to transfer the patch measurements onto a horizontal board bridging the two vertical pieces scribed to match the surface of the toerail.  Finally, the router would move along the stable jig, following the patch cut-out and remove the bad wood.  I spent just an hour on this concept before deciding to abandon it to a less-Rube-Goldberg approach:  hammer and chisel.

     So during the previous day's work on Rhino, I applied tracing paper to the toerail and marked the worst of the water and sun damage on the paper.  Using some leftover counter top laminate I had in the shop, I created a flexible template for what would eventually become the dutchman patches.  I taped the  tracing paper onto the surface the laminate, and then used a straight-edge and a utility knife to remove the interior of the patch template.

Below, the port dutchman patch marked and ready to be cut out.

Below, the starboard dutchman template prepared and ready for use on the toerail.

Once the templates were prepared, I ventured over to Rhino and placed them on the toerails to transfer the eventual dutchman patch measurements.  In the picture below, I have traced the dutchman template and am in the process of removing the bad material with hammer and wood chisel.  The intent is to remove as little material as possible, yet to rid the rails of rot.

Finally, the port toerail showing removal of the compromised wood, the void would require further shaping in order to receive the dutchman patch. The dutchman patches will be set with thickened epoxy instead of wood glue in order to tie in the surrounding material, adding strength and stability.  Smaller voids across the surface of the bow section will be filled with paste stain - Interlux paste stain wood filler.  The paste stain is appropriate for a boat of this construction and vintage; and will tie in the balance of handrail and toerails with the preparations made on the bow.

March 10th, 2013 - Total Time 4 hrs

Initial Inspection

The scope of the varnish work widened upon my initial inspection of Rhino's brightwork.  I quickly determined that some repair work would be required prior to applying varnish to the surfaces.  The subsurface damage is limited to Rhino's bow region, and with good reason.  The picture below provides explanation for why a few significant dutchman repairs are on order:  her bow dock lines have, through patient attenuation of the toerail's protective varnish, allowed water ingress and subsequent wood rot.  The repair will be one of marking damaged wood, removal, and then patching (dutchman) with new wood.  The species is mahogany (originally Philippine mahogany). I will propose an alternative chock to prevent further damage.

The forward port toerail near the port bow chock; damaged section approximately 30" in length.

The forward starboard toerail near the starboard bow chock; damaged section approximately 30" in length.

Port bow showing severe checking in the wood's surface.

Starboard bow showing sever checking in the wood's surface.