Humble Beginnings

Humble Beginnings: The Boat Rises From the Ground. 

(Well the temporary parts)

June 6, 2010

The start is always exciting.  The beginning of any boat whether its a small canoe or a 100 ft cruiser is building a jig onto which patterns for each station are mounted.  The boat is usually begun upside down for easier access to the hull and easier placement of the station forms.  In a small craft these are temporary cross sectional patterns cut out of plywood (or dimensional wood depending of style) which will control the shape of the hull.  Longitudinal battens are then strung between these plywood patterns forming a three dimensional manifestation of the hull which resembles a wire mesh 3-D model.  This is the most exciting point in boat building as far as I'm concerned because it is the first time that you can imagine the hull shape at actual size.  These bones of the boat are then covered with the hull material whether its cedar strip, plywood, canvas, or planking.  Then the hull is sanded smooth.  These steps are ubiquitous in boat building.  In fiberglass construction, the results form a plug that is coated in release paint and heavily fiberglassed.  The fiberglass is then popped off the plug forming a mold.  In traditional wood construction, the station forms are frames either bent or sawn and attached to the keel.  The longitudinal battens are then temporary and will be replaced with actual planking.  In this project, the hull is cold molded plywood.  This means that the majority of the stations are permanent plywood bulkheads with sawn frames attached.  There will be a few temporary bulkheads to assure the proper shape of the hull.  Regardless of construction technique, the start is usually the jig.

The boat jig.  Constructed out of 2X6s and leveled and trued with a transit level.  This jig is 50 feet long.  Any mistakes here get broadcast throughout the construction.  The bow is forward.

 The jig is laid out in the figure above.  I actually chose not to fasten the jig to the floor.  This will allow for minor adjustments as the boat is built.  There is a line attached to the walls fore and aft of the jig that runs the centerline of the jig.  I used this to monitor the placement of the jig and used it as the official centerline of the boat.  I'm still not sure of the wisdom of this but it worked out fine.  The centerline was one of the major references in which all measurements are made.  The other is the waterline.  The water line is a fixed distance from the outside "rails" that run the length of the jig and of course its where the actual water line should be in the fully loaded boat.  The technical term is the design water line.  With these two measurements along with lateral placement, any part can be positioned on the jig.

I'd like to insert a few words about building the jig since I am now finishing the hull.  I added plywood gussets and cross bracing to the jig to improve stability and strength.  I'd like to stress how glad I am that I did that and would have even done more knowing what I know now.  The boat becomes extremely heavy and walking and working on the hull can cause the jig to jiggle quite a bit.  It's tolerable and should hold up fine until I flip the boat over but I would not have been happy with the jig with the original design.  So here are a few pointers:

1)  Build the jig strong using at least 2X6 lumber with minimum knots. 
2)  Use gussets and cross bracing to prevent rocking and swaying.
3)  Do not use drywall screws!  Drywall screws are brittle and will not hold up against any motion.  They are also known for snapping under loads.  16d nails are your friend.  They will provide much more strength and security to the jig and are much cheaper.  I actually use drywall screws to mock up the jig and then go back and use 16d nails to finish the job up.  

The next task will be to start making the bulkheads.  At this point I haven't actually spent much money on the boat and still don't have all that much money to actually spend.  Marine plywood is very expensive although I have found a surprisingly cheap source from Noah's Marine based in Canada.  Still, at this point I needed to start with the temporary bulkheads which are made from common construction grade 3/4" plywood.  It was a good place to get my hands wet.  My plans have full size patterns for these bulkheads so the technique is to put enough plywood together to make a bulkhead and lay the pattern over the wood.  I used carbon paper and traced the lines with a smooth stylis.  This transferred the hull shape without any damage to the patterns.  Although I will say that it was not so easy as just following the lines.  The lines on the patterns were the profile of the bottom of the hull.  The thickness of the actual hull had to be subtracted from the patterns before the bulkhead shape could be realized.

The first bulkhead albeit temporary.  This bulkhead gave an impression of what I was attempting to build.  Woah!  This is going to be a large vessel.

Actually, this was the smaller of the two temporary bulkheads.  I was able to raise this on the jig by myself.  Most of the others required at least two people.

Yes, I'm damn proud I have the temporary bulkheads in place.  The bulkheads are actually placed by the frames that are screwed to the back.  Even though its does not look symmetrical, the water line and center line are placed within an 1/8" accuracy. 

The back of the second bulkhead showing the 2X6 frame.  The guy with the shirt off is Zach who use to work for me.  He is very talented and hark working guy who is capable of anything including getting strung out on meth and stealing thousands of dollars worth of copper from me.  Caught him practically red handed and still couldn't get him arrested and yes I pressed charges.  That of course happened quite a bit after this photo was taken.

Al Kuhn giving me a hand.  I couldn't have handled this one without him.  Actually this project would have never happened without him.

Push.  Yes, building a boat is hard work and yes Al almost always wears sandals and shorts.

We are having a blast.  I use drywall screws for all temporary work.  It allows me to remove the temporary work without damaging the permanent pieces.  This actually caused a bit of a problem when I temporarily fastened the floor timbers in place.  As the white oak timbers seasoned the drywall screws became a permanent part of the boat.  When I had to replane the floor boards (see later posts) I had to grind the screws down before replaning.  

There they are.  The first two temporary bulkheads installed.  At this point, there is still not  a single permanent part on the boat but if you squint real hard you might start seeing a boat.  Well, I guess you'd have to be there.  We were certainly getting a sense of the size of this boat that I was building.  This boat is going to be a beast.