Tuesday, December 3, 2019

December 2019

December 3

Well, I finally finished up the hull and all that sanding.  I went over it pretty well and filled all the little pin holes and dimples.  I'm sure I missed one but I'll find those before the paint goes on.  Right now it's time to prepare to flip hull over and start working on the inside.  To that end, I've removed all the scaffolding that will be in the way leaving just 30 feet on the wall side to attach pulleys and have people stationed for the flip.

Flipping the hull is a bit of a misnomer.  I'm actually building a jig so that I can roll the hull over until it is right.  I will use six 2 ton chain hoist.  Two to roll the hull over and they will initially be attached to the keel and two of the 6x6 posts.  Two also attached to the keel but pulling the opposite way to prevent the hull from rolling back (I might get away with using one ton hoists here).  Two attached to the pivot point on the ground to ensure the boat rolls instead of scoots.

A nice view from a ladder near the shop corner.  That's Fig in the door way.  He likes to help.

The hull looks even larger when not wrapped in scaffolding.
The first thing was to get a roundish outline to build the rollers.

Adding 2x10s to follow the outline.  This probably would have been easier to use an octagon but the round roller has fewer stress points and easier balancing points to take a break.


I took the aft one down and made an identical one for the front.  I had to customize it a little  to fit properly.   The trick was to make them identical.  Now it's time to layer on the wood for strength.

Making progress.

Essentially we have two layers of 2" lumber with 3/4" plywood sandwiched in between.  I've maintained contact with the hull as much as possible in at least the plywood and one layer of 2" lumber.  All of the joints will be through bolted together.  It will be bolted to the gunwale, building jig frame and into the keel.     

I almost forgot I needed to install the skeg keel stump.  This is the first of 5 or so pieces that make up the skeg keel.  The rudder will attach here as well as the prop shaft.  I need to install this before flipping the hull to ensure that I get the bolt holes drilled correctly.  I shaped the face that attaches to the hull a bit so that there was only a small gap.  I used two layers of woven glass between to make up the small gaps.  One thing I did a little different is that I used thickened epoxy (pea-nut butter consistency) just inside the edge of where the keel stump mates with the hull.  This held the glass in place and acted like a dam for the un-thickened epoxy.  I used temporary bolts to create pressure to squeeze out all the air and used aluminum tape around the seam so that the epoxy would not seep out.


It was very important to make sure that the skeg keel is perfectly in line with the hull.  I also used a sensitive bubble level to ensure that the skeg was not tilted to one side.  I tightened the bolts a little one after the other ensuring that I brought the skeg back to level each time.
 After the epoxy became tacky, I removed the tape and used thickened epoxy to make a fillet around the seam.
The fillet looks a little rough but it won't take much to clean up.  Having the seam a little tacky really made filleting the joint difficult but now I'll have a chemical bond between the epoxy and fillet joint.  I also had a little glass sticking out of the joint which ended up in the fillet.  That just means more strength.