Settee top installed, and other updates

 Well, it has been awhile since my last update, but progress has been steady (and slow). I finished installing and taping the forward bunk and the cockpit floor.  I spent quite a lot of time preparing the settee top for installation.  The top has two access panels in it for storage with rims made out of marine ply.  Seemed like an easy and quick job, but it took me a couple weeks to cut the ply rims, glass them, and laminate them onto the settee top.  In any case, the top and openings look very neat and should finish well (if we ever get to that stage!)  I also cut the reinforcement for the side of the companionway out of white oak and glued it to the bulkhead.  In the photo looking aft, you can see both the settee top with access ports and the companionway with reinforcement.

Here is a view of the underside of the settee top after it was installed in the port hull half.  The panel has been glued in place and a fillet run along all seams.  I also went back and added partial fillets along some other seams on adjoining panels.  I left the top six inches of panels yet to be joined to panels in the starboard half lose for final tweaking once the hull halves are joined.  Next I will tape the filleted seams and apply peel-ply for a clean finish.  I am very happy with the taping when I use peel-ply.  Although the peel-ply is sometimes a headache to apply, it gives such a nice finish that it is definitely the way to go.  But you also have to remember to peel it off before installing additional elements.  I came close to glueing panels on top of peel-ply a couple times today.

Here is the underside of the settee top for the starboard hull half.  I prepped both panels so it won't take as long to assemble the starboard half.  The marine ply rims are taped to the panels on the underside.  Since we will be sitting on, crawling over, and generally abusing the settee top, I figured it was worth applying a little extra reinforcing.  For a clean finish, the rims were laminated on the panels on the vacuum table.  The peel-ply is still on the panel shown.

Once the settee top is taped in place, I will install the settee front, and then we just have the cockpit seat to install.  So hopefully this stage of construction is close to finished, but no guarantees!

Bulkheads in, other panels in progress

 Progress continues on the interior of the port half of the main hull.  Last week I finished dry fitting all of the panels.  This took quite a bit longer than I expected (the rule of pi, everything takes about a factor of 3.1415... longer than planned).  But I was happy in the end because all of the panels sat plumb and level in the intended locations.

 I also installed all of the bulkheads.  Final installation was done in four basic steps:
1 - Glue the bulkheads in place with just enough epoxy-microballoon putty to hold the panel in place and let set.
2 - Once the glue sets enough to keep the panel from moving, apply a heavy fillet between the bulkhead and the hull, and let set.
3 - When the fillet sets enough to hold its shape, apply the glass tape and epoxy over the fillet.
4 - Before the tape starts to set, apply peel-ply for a super-clean finish.
I thought this all went fairly well, although the peel-ply was a bit tricky to conform to the curves without pulling up.  Unfortunately, today I removed some of the peel ply and discovered several bubble under the tape.  I think I pulled up the tape in a few places while fighting with the peel-ply.  Luckily glass and epoxy is forgiving, so I pulled out the sander and ground out the bubbles.  I'll go back and apply some additional patches to fully restore the strength of the join.

This weekend, after dealing with the bubbles, I moved on to installing the other panels.  I started with the forward bunk and the cockpit floor.  The installation process is basically the same as with the bulkheads.  The only real difference is the panels get lighter fillets and tape than the bulkheads.  In this overview of the hull, you will also notice that I added some braces on top of the panels.  These braces hold the panels vertical.  I am not joining the panels to any vertical surfaces, e.g. bulkheads, so I can make final adjustments when I join the two halves of the hull together.  Hopefully I won't need to make big adjustments to get the halves to match, but best to have some flexibility.

Here is a view inside the hull looking aft from the forward bunk.  The forward bunk has several additional reinforcements because the beams that link the floats to the main hull tie into this section of the hull.  For example, you may notice the unidirectional glass at the bottom of the bunk near the bulkhead.  The bunk and cockpit floor are now glued in place. Next I'll continue with light fillets and tape the panels permanently.

Final bulkheads fitting

 I am finally making some progress on fitting the bulkheads and other panels.  Here is a view of the port side main hull with most of the panels fitted and ready for taping.  The only panels remaining to fit are the cockpit floor.  I spent several days (a few hours a day) very carefully locating the panels on the inside surface of the hull.  This takes some effort due to the complex surface and specific orientation of some bulkheads.  But once I had all of the reference lines drawn out in detail, the process of fitting the panels is much easier.  Plus, these panels need to match the to-be-built starboard side along the center line precisely, so they need to be carefully positioned.

This is a view from inside the v-berth in the bow looking aft at the settee (to the left in the photo) and cockpit beyond.  You may notice the small wood blocks that hold the panels in position.  These work well for ensuring the panels stay where I want them to be while fitting the other panels.  The wood cross members are stabilizing the settee top (vertical panel on left) while I tweak the fit of the settee front (sorta horizontal panel on the left).

Here is a close up view of the transom bulkhead to show the alignment blocks.  These blocks will hold the panel in position while the initial epoxy glue locks them in place.  Then the blocks will be removed and the screw holes filled prior to filleting the panel.  The glass tape over the fillet will permanently seal the holes.  Glass work is very forgiving as long as I don't undermine the integrity of the structure by cutting too much fiber.  A few small holes makes the construction much more precise and saves a lot of headaches.

Do not attempt to adjust your screen ... I have rotated the image to assist you in visualizing the method of my madness ...  Actually, I thought it would be helpful to show the hull in the correct orientation so we can get an idea of what it is going to look like once finished.  For the first time, thanks to modern imagery magic, we can see the interior spaces of the trimaran as they are intended to be.  Note the v-berth in the forward section, the settee amidship, and the cockpit starting to come together.

Fitting bulkheads in main hull

 I know its been awhile since the last post, but I think I pretty much exhausted interesting photos of flat panels and vacuum tables.  I am finally done laminating the various panels (at least those on the full size plans).  So now I am starting to fit the panels into the hull.  This takes some careful layout due to the complex surface and the need for panels to be installed with specific orientations.  The laser level helps to layout the straight lines along the curved hull surface, but a little creativity is needed to figure out how to support the laser at times.

 In these photo, the panels are just set in place to determine if everything is fitting roughly.  You may notice the red layout lines drawn on the hull with the help of the laser.  So far all panels seem to match the contours well enough.  Now I will start trimming the edges that sit on the hull to match the curvature more closely while also lining up the top edges with the hull centerline.  Should be more entertaining than flat panels on a flat table ...

Vacuum bagging tutorial

Since we are spending most of our boat building time on laminating panels on the vacuum table now, I though it would be useful to describe my process.  This is basically the same process described by other, more professional types of experts.  Note that in this example I am just laminating one side of the panels at a time so I don't have to punch a million tiny holes in these foam sheets.  Laminating both sides simultaneously is quicker (by almost exactly a factor of two), and can use less material.  If I were to do this again, I would buy some perforated foam core to make panels.  Nonetheless, the end product is just as good in either case, and plain foam core is a bit cheaper.  So here we go (take notes as there will be a test at the end!):

1)  Start by preparing all of your materials.  You will need:
- The foam core cut to the desired size and shape, and pre-sanded to remove any residue that would inhibit bonding with the epoxy,
- The glass fabric cut a couple inches oversized,
-  Peel-ply cut a little bigger still,
-  Perforated release film so it doesn't stick to the bag, and
-  Breather fabric cut large so the air can get out.
I also have a rectangle of sealing tape laid out on my table top with the vacuum bag sealed along the back edge.  I also have the vacuum feedthrough installed in my vacuum bag and the pump ready to go.  Note the vacuum bag is really just the top layer that seals to the table top.  The table top forms the bottom half of the "bag."  On my roll cart I have my epoxy (paint) tray and roller set up and waiting.  The more you can do before you mix epoxy, the better.

2) Now that we are ready to laminate, let's mix some epoxy!  I use pre-marked mixing cups to make measuring easy.  These cups from Noah's have marks for various mixing ratios and quantities.  I use an electric drill with a paint mixer attachment to mix the resin and hardener.  I have found I need about 45-mL of mixed epoxy for every square foot of laminating.  Regardless of quantity, I always mix for 2-minutes.  I adjust speed of the drill to compensate for quantity, and try to avoid sucking air into the mix.

Here is a tip I came up with for joining pieces of foam core into a single panel.  I just staple the pieces together on the face NOT being laminated.  This hold the seam together until the first side is laminated.  When I flip the panel, I remove the staples and epoxy fills the holes during the second lamination.  In this case, the panel needs to be about 47-inches long, but the  sheet of foam was only 46" wide.  So I just used a piece of scrap foam to cut a 1-inch strip and joined it to the larger panel.  Once laminated, it is as strong or stronger than a single piece of foam core.




 3)  Now it is time to wet the foam core with a good coating of epoxy.  You could skip this and do a "dry lay up," but I think it is good to work some epoxy into the foam texture before laying on the glass fabric.  Although air entrapment should not be an issue on a vacuum lamination, I figure the less air the pump has to suck out, the less likely there will be an unexpected issue.

4) Once the foam is wet, I carefully lay the glass fabric on the foam, ensuring there is glass over all of the edges.  I then stroke the fabric along the direction of the fibers to get rid of any wrinkles.  Be careful here or you can make it worse.

 5) Now you can roll on more epoxy to saturate the glass.  I find it works best to roll on one stripe of epoxy at a time.  Then move to the next stripe while the previous one soaked in to the glass.  You know it is working because the glass disappears.  In this photo you can see how the glass becomes transparent when saturated (right half).  You don't need to over-saturate the glass, just enough to make it transparent with no white strands remaining.

6) As soon as the glass is saturated with epoxy, lay the peel-ply on top.  Try to lay it out carefully with no wrinkles.  Once it starts to absorb the epoxy It will become more difficult to adjust.  If you move it around too much it will start to drag the glass which can make a mess.  In general, less handling is better with all steps of the lay up.  The peel-ply serves a couple purposes.  First, it absorbed excess epoxy, which result in a lighter, stronger part.  Second, once peeled off, it creates a surface that is ideal for bonding to epoxy during later assembly.  Third, it creates a very smooth and uniform surface.

7) Now roll over the peel-ply to set it into the wet epoxy.  I start by making a cross through the center of the panel.  Roll slowly so the peel-ply sticks to the panel and not your roller.  Don't add any extra epoxy, rather let the peel-ply soak up the excess epoxy from the glass.  This step is another that is not really necessary, but I think it helps avoid problems later.  I think this step helps ensure the peel-ply doesn't get creased when pressed under vacuum.

8) Now you can lay the perforated release film on top of the peel-ply.  This film prevents the breather fabric from sticking to the part being laminated.  The film has small holes punched through to allow air and excess epoxy to escape.

9)  Next on the stack is the breather fabric.  There are various types, but I like the high-loft type that feels like a fluffy blanket.  The breather need to overlap all edges to give air a path to escape when the vacuum starts.  I cut it long and then fold a pleat at one side where the vacuum feedthrough will sit to serve as a manifold for air escaping under the pressure.

 10)  Now the vacuum bag layer is layer on top and sealed to the table via the sealing tape (yellow) around the perimeter.  This takes some practice to get the seal uniform without lots of leaky wrinkles.  Be careful about pulling the bag too tight when sealing because it may pull the sealing tape off the table once the vacuum starts and the bag stretches to conform to the shape of the panel.  Notice the vacuum feed trough nipple at the far end of the table on top of the breather fabric pleats.

 11) On goes the vacuum hose and the pump starts sucking the air out.  I continue to massage the seal to work out leaks.  I found my ears to be the best leak detectors.  I walk along the seam with by ear almost touching the table and listen for leaks.  Once the seal is tight my pump runs until it reaches its set point and then kicks off until the pressure creeps back up.  You can also use a continuous running pump with no reservoir.

As the atmosphere presses down on the evacuated stack of materials, excess epoxy will seep through the holes in the perforated release film and get absorbed in the breather fabric.  This is good for making a strong, lightweight panel.  I am working at almost 7000 feet altitude, so I don't have as much atmosphere to press down with as those of you at sea level, but it is still adequate to make an excellent panel.

 12)  After the epoxy cures for a few hours (6-12 hours, or more, depending on the temperature), you can remove the panel.  If you are careful, the vacuum bag with sealing tape and the release film can be reused.  The breather is best used only once.  The excess glass and peel-ply can now be trimmed with a sharp knife.  If you do this within 24-hours, the knife will cut the excess off very easily and cleanly.  If you let the epoxy fully cure over days, it gets tougher and may require more effort to trim.

And Voila! here is your laminated panel (or half laminated if this was the first side).  To do the other side, just repeat the above steps.  With a little practice, this is very efficient and you will be able to make super-strong lightweight panels.  Initially the process can be frustrating due to excessive mucking with the layers.  Remember, less handling is always better, and the process is generally self-correcting.  So far I have not had any panels come out looking bad, much less unusable.  The same cannot be said for my effort laminating by hand (see discussion about the first float half about a year ago).

Starting to install flat panels

We are still laminating bunches of flat panels on the vacuum table.  I have finished about half of the panels from the full-size plans, and also noticed there are several panels that are cut to fit.  This is going to take a couple more weeks to work through (if only the day job didn't take up so much of the day!)  However, we have now started installing these panels in the port half of the main hull.  Here is a photo of the aft cockpit and side deck installed.  Technically, these are the last components of the deck to be installed, rather than interior panels.  Nonetheless, the flat panels are starting to get used.

As we have done with other panels, e.g bulkheads, after trimming to fit, we bed the panel in epoxy putty, form a nice fillet (in this case only along the inside seams), and tape in place with 12-oz double-bias glass and epoxy.  I am also finishing these seams by applying peel-ply over the tape. Once cured, I peel off the peel-ply and the result is a smooth join with no evil epoxy-glass spikes along the edges.  You can see the result looks very clean and professional (said with a thick southern accent).  I have most of the panels ready to assemble the rest of the cockpit required at this stage, but I need a couple bulkheads before proceeding.  More to come ...

News Flash: Farrier to discontinue boat plans!

I recently saw a post from Ian Farrier announcing that he will discontinue his sailboat building plans on Sep. 25, 2012!  Apparently he is focussing his attention on developing his production boat business again.  He is currently planning to start production of his new F-22 design.  He notes there are several quality builders that are licensed to build his designs.  He also mentions availability of kit boats, which might be interesting for someone wanting to build without as much time commitment.

In any case, if you have been watching this blog with the intent of trying this yourself, you may want to get your plans very soon.