Sunday, May 27, 2012

The Piney Cove and Bead Hull Jig

Last night on our walk my Dad and I were talking and I decided to cove and bead my hull and deck planks because the wood is kind of warped and twisted and somewhat quite uneven.  VERY OFF-CENTERED like a quirky Dogfish Head brew!  Cove and beaded planks will sit much more even we thought and it turned out that they did.

I had figured it would be easy because doing the thin rail strips were so easy, but to make it easy we had to drill and tap threaded holes into the table of the shaper so we could affix the fingerboards.  That took about 4 hours and my Dad was a real hero by saving the day with his ideas and putting in all that extra time to help me!  I wanted to get the hull glued up today so that I needed not do any hard work on Memorial Day.  So after we got the table set up, we first beaded one edge and then did the cove as the cove is much more delicate when going through the planer and fingerboards and may have gotten damaged.

Below is the table of the shaper which is actually just like a router, but permanently affixed to an iron table.  Fingerboards usually run along a channel (seen at the top of the picture) but in this channel the planks were too wide so we devised a plan to clamp the fingerboards onto the table.  This proved cumbersome and time consuming so will drilled 8 holes (for two fingerboards with two holes each for two different locations) and threaded them to accept 1/4 20 allen head screws.
Below is the setup.  "The Jig" .  To run even wider planks the red fingerboards can be secured to the the set of holes further back at the bottom of the pic.  The blue fingerboard holds the wood plank down on the spinning blade, which you can't see, but it is behind the blue fingerboard in the center.  This worked out great!  Once the jig was built, the cove and bead work only took an hour and we were off to dinner!
After dinner and a walk through Palmyra Nature Cove I came back and glued up the hull.  I decided to go with the crappier looking planks for the hull instead of the deck.  It just seemed right to do it this way.  They aren't crappier anyway, just different.  The deck will be awesome though.

The first thing I did was lay out plastic on the strongback to keep the glue off of it.  
*NOTE TO SELF* Do not use super thin plastic, use visqueen.  Super thin plastic gets sucked up into the glued seams and an unfortunate struggle ensues when there is not much time.
I then set up a jig for holding the planks as I filled the cove side with Titebond III waterproof wood glue.  Painstakingly I glued each plank and pulled them together until I was able to finish and then get to the clamping stage.

After each plank was glued and pulled together by hand I first placed perfectly flat pieces of wood sometimes referred to as 'battens' (Like Batten Down the Hatches kind of battens) and tightened them down with various clamps.  You can see the battens as they have red duct tape on them to keep glue from sticking to them as well and the clamps on either end of the battens.  The battens keep the planks from springing up in the next step where they get clamped with long bar clamps.  The bar clamps span the entire width of the hull and pull all the planks together real tight and if the battens weren't across the top of the planks, they would all just pop up.  It's a pretty good system and with the cove and bead there were no longitudinal waves going the length of the board which can sometimes happen with just a "butt joint".  I am concerned how it will look as butt joints actually look really really sharp, but this is a reclaimed wood board anyway with lots of flaws that will hopefully give it character anyway, so I had nothing to lose trying the cove and bead joints.
OK so the glue looks a little messy.  I had to do the process twice.  I got it all clamped up the first time and took notice that I had one little plank in the wrong spot!  It was a mad dash to get it apart and back together again as the glue had started to set.  That's the kind occurrence that happens when you are tired, but I "Got 'er Done"!

Happy Memorial Day everyone!  Now I'm off to enjoy the rest of my Uncle's Left Nut!

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