Ama Progress

The ama has been making good progress.  The keel panels went on.  Next the seams got cleaned up and filled where the wires had been.  The wire holes were closed.

A main task before moving on was fairing the chines, bow and keel.

Here is a bow filled and capped with a thin strip of glass.  I wanted to fully close the seam.

The bows and keel were about 20mm wide when joined.  The square shape did not look too sleek, so I decided to add a foam nose piece. The top picture show the foam glued over the glass, while the bottom is after shaping.  This is Divinycell H80.  It is strong, though I worry about cosmetic damage in minor bumps.

On the keel, I used the same concept with a strip of plywood.  The plywood has the corners on one edge rounded over.  A thin bullnose was then ripped on the table saw.  #17 finish nails are place prior to gluing.  The nails will act as alignment guide once the strip is wet.  Tape at 2 inch intervals worked pretty well as clamps.  I used fast hardener and added a little 5 minute epoxy to get the glue to stick and kick faster. This is a trick off of the West System site.  Sanding then faired it into the keel panels.

Here is the glass draped and partially smoothed.

The intersection of the bow and keel fairings.

The cloth has been wet out with a roller.  This shows how the bulkhead tabs were glued to the hull panels.

Here is the hull drying prior to the first fill coat.  The skirt will be trimmed off of the shear before the epoxy fully cures.  The skirt is also handy for catching epoxy runs during wet out.

Task time: 50 hours

Total project time: 660 hours

Staging of Plywood

I have been postponing delivery of the cut plywood panels.  It has been raining and off -loading the parts from a truck into the shop without a forklift may take a while.  The wood will probably show up on Monday.

The delivery will leave me with 21 sheets of cut 4 x 8 foot plywood.  After cutting, each sheet is stacked in place with all of the scrap and surrounding borders laid out exactly the same as before cutting.  This is basically a stack of jigsaw puzzles. To move these into the shop, each loose sheet will need to be transferred separately.  There are around a 190 pieces not including scrap.

The challenge will be finding the best way to stack these. The ordering should depend on the processing usage.

The majority of parts will get one of three treatments before assembly:

1. Sheathing with 200gm/sq m glass (6oz/sq yd)
2. Sheathing with 300gm/sqM glass (8oz/sq yd)
3. Coating with just epoxy

These treatments may be done on one or both sides depending on the part.  Parts that will have to be bent later during assembly will typically only be coated on one (the inside) side.

Parts with puzzle joints must be joined prior to glassing.  The largest joined parts will be 32 feet in length, so it may make sense to do these last.

Multiple un-joined parts maybe glassed at once.  The limit to the number of parts that can be done at once is a combination of epoxy working time, parts that would fit on a 4 x 12 foot table top and my glassing skill or lack thereof.  The parts have to be grouped by the weight of glass they require.

So, how to optimally stack the parts to access them in order?  This will take a bit of scanning of the build plans to figure out which panels get which glass.  This list has to be cross referenced back to the cutting nests.   It maybe be easier to divide the nests into groups separate from the original sheets, but  then quality storage space becomes an issue.

It seems worth the effort, to streamline the sheathing.  Future builders may benefit from the information as well.  A future optimization might be to reorder the cutting based on my findings to that the sheets are stacked in a more natural order at the CNC shop.