On to the main hull!

 We are on to the main hull at last.  Once again I enlisted my neighbor to help put the port float on the storage shelf.  I still need to write a punch list of things I need to do on the floats when I install the beams, otherwise I'll likely forget half of the tasks.  After moving the float, I started tweaking the strong back.  The last couple of cross pieces have to be moved for the main hull since it is longer than the floats.  I also made fine adjustments to several other cross pieces (+/- 1-2 mm) to try to get everything just right.

And here is a nice view of the twins Portia and Starry!  Next steps are lot's of woodworking to get the main hull frame built.  The main hull is about twice as wide as the floats, so it might get tight in here.  And I have no idea where I am going to store the first half while building the second half.  Well, I guess I still have plenty of time to figure it out!

Finishing up CMMs

 We are just about done with the central mounting modules.  We glued on the beam pads and glassed the various joints and exposed foam in the channel.  Applying glass and fillets in the channel is tricky.  Definitely a good opportunity to improve my patience.  You might note that I outlined the remaining peel-ply to help me remember to remove it when we install these in the main hull (someday).  It is pretty easy to forget about the peel ply, which would lead to a real bad day sailing.

Here's another view of the nearly complete CMMs.  Once they fully cure, I will do some clean up and I need to seal the edge of the center flange (on the bottom in the photo) with glass and epoxy.  But that is it for these parts for awhile.  Again, I thought it would only take a couple hours to install the pads and finish the glass and epoxy work, but it took about six!

Taping CMMs and the essence of time

 After a wonderful Christmas day, nothing beats a day mixing epoxy and taping joints on the Central Mounting Modules.  I formed fillets in all of the corners on Christmas in preparation for taping.  Temperatures are very cold at night, so the epoxy doesn't cure, which is good in this case.  It allowed me to fillet one day and tape the next while the epoxy is still curing, resulting in a stronger bond.  I also cut the glass tape ahead of time.  Today, before mixing the first batch of epoxy, I did some final trimming to fit the glass tape around the circular bolt plate shown in the photo.  Cutting complex curves in glass fabric is a little tricky, so here is my trick ...

 The first step was to make a template out of card stock to locate the cut-out on the glass tape relative to the edges of the CMM.  I then aligned the edge of the template with the edge of the tape and traced the partial circle with a Sharpie marker.  This makes measuring quick and easy.

 Next, I used a rotary cutter to cut the curve in the glass tape, being careful to stay on the outside of the marks.  The rotary cutter does a great job of cutting without distorting the fibers in the tape.  I used a piece of plastic louver from an old window blind as a cutting surface to protect the table.  The cutter is sharp enough to leave a nasty cut in the laminate on my vacuum table.

 And, there it is, a perfectly cut opening to fit around the bolt plate.  Sorry for the poor contrast of white fabric on white louvre on white table.

 Now all of the tape is cut to size and the fillets are firm but still curing.  I estimated it would take a couple hours to tape both CMMs, after which I would relax and enjoy some time playing with my daughter's Christmas presents.  The boat house gets into the mid-60s during the day, and then rapidly cools off after about 3:00.  Starting at about noon, I figured I would have plenty of time ...

Seven hours and 1.5 liters of epoxy later, I finally finished!  And, no, I did not have any difficulties, aside from the plummeting temperatures.  It was just a lot of detailed work placing and wetting out each piece of material.  I did move from the boat house to the sun room when temperatures fell into  the 40's.  It is hard to tell if the epoxy is gelling or just getting thick from being too cold in these conditions. The CMMs are now in the heated storage room to cure overnight.  Funny how things always seem to take longer than anticipated.

Port ports

 The port float is now done, or at least as done as it will get until the beams are installed.  I am putting together short punch lists of details I need to remember to take care of when I install the beams and chainplates.  I have delayed installation of the chainplates until I know more specifics of the rigging I will use.  And there are a few minor touch ups needed.

Here is a view of the forward access port and main hatch on the port float being dry fitted.  I will need to add prep of the holes for bolting the hatches to the hull to my punch list.  The fit is good, and the mounting surfaces are fair, so the hatches should keep the water out.

Of course, the hatches also open properly without binding.  Just replace the wood floor with blue water and the shop wall with a clear horizon and we are ready to set sail!  In the meantime, we are on to building the form frame for the main hull (hooray!)

Central Mounting Modules glued

 We finished the initial assembly of both the forward and aft Central Mounting Modules.  In this photo you can see the last end of the last module being clamped together while the glue sets.  The filler putty that the plates are bed in tends to slowly ooze down and out of the vertical joints.  The putty is a mix of epoxy, cabosil, and microballoons.  More cabosil or microballoons would reduce the flow, but I found it easy enough to just babysit the assembly until the epoxy kicks.  I will add more putty to form fillets in all of the corners after the initial glue cures.  The CMMs are rather fragile with just thin lines of glue, but the fillets and glass tape will make them strong and capable of distributing the large forces applied by the beams.

Here is the first CMM I assembled in the correct orientation.  The wood beam pads will be mounted on either side of the slot at the top corners.  The "upper folding strut"will be bolted into the slot as part of the mechanism that supports the beams.  You may notice the scribbles all over the CMM.  These are marks to remind me that these areas still have peel-ply so I don't try to install the CMMs with the peel-ply still on.  I have been removing strips of peel-ply as I assemble the various components of the CMMs.  I am trying to keep the peel-ply on as long as possible so the surfaces are clean when installed into the main hull.

Assembling the central mounting modules

Last weekend we started assembling the central mounting modules.  The assembly requires the use of a jig described in the plans that I built last winter.  As you can see in the photo, a few clamps come in handy as well.  The assembly at the far end was done last week, and is now set.  Today I glued up the other end, currently clamped and curing.  The glue is epoxy thickened with cabosil.  I also use a putty to fill in the gaps.  Typically I wet all of the mating surfaces with the thickened epoxy glue to ensure good adhesion of the putty.  Then I apply a bead of putty and mate the pieces.  Following a little cleanup I leave it to cure.  I don't try to fillet and tape it until the initial glue is cured.  It is just too much hassle to work around the clamps and jig.  Over the weekend I plan to assemble the other CMM.  Hopefully I'll be able to fillet and tape both CMMs next weekend.  That should put us on track to be done with the CMMs before Christmas.

A couple posts ago I showed the woodworking I was doing to fabricate the beam pads that will go on the CMMs.  Well, here is another picture of the pads after all the cuts were complete.  It was a lot of work milling these to the precise dimensions, but I just love the look and feel of a well machined part, be it wood or metal (or fiber-reinforced boat hull).

After some sanding and prep, the wood beam pads were glassed on three sides.  The other sides are glassed once the CMMs are installed in the main hull.  I masked the unglassed sides with clear packing tape prior to applying the glass to keep the surfaces clean.  I just need to do some final sanding and these will be ready to be attached to the CMMs.  (And no, this is not suppose to be an advertisement for a trampoline company!)

Finishing touches on access holes

I know it has been a while since I last posted an update.  There hasn't been too much done on the port float that wasn't already discussed when we were finishing the starboard float.  We finished trimming out the four access ports.  I applied the fairing putty around the ports to blend in the glass reinforcing.  Then winter showed up and dumped snow on us.  So I've been a little slow to get out and sand the fairing putty.  But I did start on it today.  Here is a view of the forward access port on the port hull after fairing. It looks pretty good, though I can still feel the transition from the hull to the reinforcing patch, so I will add a second pass with putty to the punch list.

Here is another view of the forward access port with the screw-in port cover dry fitted.  I think it looks great.  The slightly recessed support plate makes the port flow into the rest of the hull, almost professional looking!  You can see the other three openings in the background awaiting the same attention.  The next round of winter storms is expected next week, so finishing these ports is high on my to-do list for this weekend.  It actually only takes less then an hour per port, so no problem.