Sunday, June 28, 2015

Attaching Ama Panels

The last week has been a lot of gluing, filleting and sanding on the main ama planks.  After wiring things into place, I did an initial glue up.  Using a small syringe, I put a bead of thickened adhesive epoxy along the bulkhead plank intersections.  A small syringe allows you to force a bit of epoxy between the two surfaces.

The area should be cleaned up with a chisel stick to avoid excess sanding.  The seam and any remaining glue still needs to be sanded back dull.  A wider fillet is then put over the corners to provide most of the strength.  I used larger syringes for applying a fillet bead.  Many people use pastry bags, but the corners were a bit tight for my hands and a bag.  The fillets are then sanded a bit. The sanding is mandatory in the ballast tanks, as they will get a couple more barrier coats of epoxy over all the seams.



Stem wired for glueing.





Initial glue joint between bulkhead and plank.


The plans call for solid wood inner stems behind the bows.  I had some black walnut around which has a very high compressive strength and does not weigh a lot more than fir or laminated plywood blocks.

Shaping the stems was pretty ad hoc.   You don't really know the dimensions and angles until the panels are joined.  Once the panels are joined, there is not much room for measurements and visual inspections of the inserted pieces.

I decided to go with two parts per inner stem.  I figured that any inaccuracy in tapering and shaping could be taken up by sliding one wedge forward past the other into the small vee area.



The stem pieces during shaping.  In addition to the vee shape, the leading edge curves a bit.





Dry fitting the inner stem.  The pieces did not end up perfectly symmetrical, but it should be strong.  You can see where the stringers come together at the bottom of the picture.



Task time: 28 hours
Total project time: 638 hours

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