Cleats, Floors, Modifications

I left the cleats in the rear section of the boat to cure while I added cleats to the front compartment.  This compartment will be filled with foam flotation panels and sealed.  There will be an inspection plate installed (you can see part of the hole for it at the bottom of the picture) and a drain plug at the bottom.  There will be a deck installed on top of the bow compartment and the storage compartment, and this deck will be the floor of the anchor well.

Cleats at Top of Bow Compartment

The cleats on the sides are cut very thin so that bending them will not distort the hull shape.  I also pre-bent them with a heat gun as shown here:

Heat-Bending Bow Cleat

This worked very well, though it was not called for in the plans.  Even though I made the cleat thin as was required so it would bend more easily, they still distorted the hull shape when I tested them, so I heat-bent them.
  

There will be no side cleats at the top of the storage compartment even though the anchor-well deck extends back over it--this is probably because the side walls are much longer here and the cleat, no matter how thin, would still distort the hull shape.  That area is accessible from below so the instructions call for epoxy fillets.  The fillets will be very difficult to put in place, so I am tempted to make cleats and heat-bend them also.  Will need to give this some more thought.

I have also added cleats on the sides of the centerboard trunk to help support the cockpit seat and provide a surface to attach to:

CB Trunk Cleats

 

Transom Compartment Cleats

Here are the cleats in the transom compartment.  You can begin to see how the cockpit will go together.  There will be seats on each side, and you can see cleats for the seat sides and floor at the middle.  It appears here that the seats will be extremely wide, but there are small storage and floatation compartments and seat backs to be installed on top of the seats at the gunwales, leaving the seats a more natural width.  Floatation foam will be added below the floor.  The cockpit floor will be above the waterline, so that allows drain holes to be drilled in the transom at the rear end of the floor, making the cockpit self-draining.

Transom Compartment Covered and Heated

I have moved the plastic sheeting that was covering the entire boat to cover only the transom compartment while the transom cleats cure.  There is a small electric heater inside the transom compartment.  When the plastic sheet was covering the entire boat, the heater was sitting in front of the CB trunk.  This kept everything at 70 - 75 degrees while the cleat epoxy cured.

Starting Floorboard Project

It is already time to start fitting the floorboards.  That is because later on they will be much harder to get at.  Here you can see the first two boards sitting by the CB trunk.  I will have to cut a notch in each of them for the trunk.  The three-inch-wide boards will be placed 1/8" apart.

Below the floorboards you can see some of the flexible conduit which will be run on both sides of the boat from the storage (and battery) compartment to the upper-rear corners of the transom.  These will both be long enough to reach near the top of the boat and will be bent downwards at the ends to keep any casual water out.

I have placed the conduits in temporarily so I can see how to deal with the flooring at bulkhead 8:

Conduit Entering Transom Compartment Through BH 8

This is where I have made several modifications to the original plans.

First, there was to be no conduit, just loose wiring, and there were wiring holes on the starboard side only.  I added conduit holes to the port side and decided to use conduit to facilitate running the wiring.

Second, there were no conduit holes in bulkhead 8.  The wiring was only supposed to go through BH 7 then up BH 8 and somehow fed to the transom, where at the very least there is the need to power a running light.  I drilled the holes and will run flexible conduit that will go back to the rear corners of the transom, up through the cockpit seats, and into the side storage compartments.  The holes in BH 8 and the cockpit seat will be sealed around the conduit with marine sealant foam.

Third, there was to be no drain hole at the bottom of BH 8 (you can barely see that I have drilled one).  There were two drain plugs included with the Hull Hardware Kit, and it seems to me that a drain hole was originally intended for BH 8.  There will be two large lazarette doors in the cockpit seats, and water has been known to get into the transom compartment through them.  The transom compartment is sealed as part of the boat safety, so the only way to get the water out was to reach down through lazarette doors, then pump and sponge it out--not that easy with floatation foam under the floor.  So I have placed a drain plug that will allow me to periodically drain out all but a teaspoon or two of water.  (And I could add a few drops of Clorox or some other chemical to it to prevent mildew--will have to find out what is best to use with fiberglass.)

And fourth, the floorboards would normally go all the way back to BH 8.  What I have in there now are standard 8-foot boards (the lengths don't match--haven't trimmed them yet).  So I would have had to buy 10-foot boards and cut them down to about 8' 6".  But with my other modifications I don't want them to go all the way to BH 8.  I will instead build a small lift-out section that will reach from the ends of the floorboards to BH 8 so that I can get to the drain plug.  That means building another floorboard joist or cleat at the ends of the 8' floorboards.  I will probably make it out of 1 x 3 lumber (not a lot of weight on the floor back there where one can only lie down).  You can also see the lines for the floorboard cleat on BH 8.  I haven't installed it yet because I have to figure how it is going to work with the drain plug and conduit.  It will have to be made in either two or four pieces, and a cutout made in one or two of the floorboards to accommodate the conduits.  The cutouts will most likely be in the lift-out section, which will actually make that part a lot easier.

MAS Epoxy Cure Schedules (Revised by Me)

MAS Epoxies Cure Schedules

Resin Hardener Mix
	Resin/Slow	Resin/Medium	Resin/Fast
Temp. ⁰F	Pot Life / Thin Film Set / Full Cure
86⁰	17.25m/3:45h/3.75d*	9.75m/2:25h/63h*	5m/1:30h/1.5d*
77⁰	23m/5h/5d	13m/3h/3.5d	7m/2h/2d
68⁰	34.5m/7.5h/7.5d	19.5m/4.5h/5.25d	10.5m/3h/3d
60⁰	44.5m/10h/10d	26m/6h/7d	14m/4h/4d
50⁰	69m/15h/15d*	39m/9h/10.5d*	21m/6h/6d*
s = seconds;  m = minutes;  d = days

* Not recommended

Note:  For clear coating and bonding resin must remain 60⁰ F to 80⁰ F.  

Above is my modified version of the cure schedule.  I decided upon it after much thought and study of posts by John Harris, CEO of Chesapeake Light Craft.

Moving Right Along

Sanding Transom Compartment Fillets

Here I am just finishing up the sanding of the fillets in the transom compartment, next the entire inside of the compartment is sanded down so the epoxy will stick.

Sanding Transom Compartment

 

Transom Compartment 'Glassed

The fiberglass cloth has been added to the transom compartment and the first wetting-out coat of epoxy added.  I waited about 4 hours and added the fill coat, than another 4 hours or so and the gloss coat.  The pictures of the second and third coats would not have looked much different so didn't take any.  By waiting until the epoxy is tacky but not starting to cure, you can add subsequent coats without sanding and get a good chemical bond.  You have to do this for the fill coat because sanding would damage the exposed fibers.  I also follow this procedure for the gloss coat when I can to save on sanding and to get a better bond.

Cockpit Cleats Glued in Place

The cleats that will help support the footwell floor and cockpit seats have been added to bulkhead 8 and most of bulkhead 7.

Bulkhead 7--Two Cleats Missing

I cut the cleats for bulkheads 7 and 8 a couple months ago and forgot I had not cut all of them for BH 7 yet.  In this closer shot from aft you can see that two cleats are missing--the vertical cleat for the port (left) side and one that goes along the bottom.  I'll cut and add those in the next day or so.  

Some Real Progress At Last!

The next step is fiberglassing the hull floor.  The rear (transom) compartment and the storage compartment are not quite ready yet, I have to sand the fillets some more, so I am making paper templates for all the floor sections.

Rear Cabin Template

 Here is the first template in place.  I have made all the cabin floor templates and the next step is to use them to make two fiberglass panels each, one for the port side and one for the starboard side of the cabin.

Cabin Floor Templates

Here's a shot of all the cabin floor templates in place.

Port Side 'Glassed

I have laid in all the fiberglass panels for the port side of the cabin floor and added the wetting-out epoxy coat.

The first starboard side fiberglass panel is in place but not epoxied as yet.  As you can see, the panels overlap about four inches over the keelson and from front to back.  They also go up three or four inches on all the bulkheads and floors and the side panels.

First Wetting-Out Coat Applied to Both Sides

 I have glassed and wetted-out the fiberglass panels on both the port and starboard sides of the cabin floor.  In an hour or so I'll go out and add the second (fill) coat of epoxy.

More Fillet Work & Getting Ready to 'Glass Inside of Hull

About all I have been able to get done since building the rudder is sanding, sanding, and sanding the fillets.  They are starting to look pretty good--I don't have any pictures, but the newer fillets don't look much different than the earlier ones.  The fillets in the rear compartment were acceptable, but I felt they needed some smoothing.  There were quite a few low spots, but they were so shallow I'm not sure they would have caused any problems.  However, once that compartment is sealed up I will never be able to see in there again and if a delamination or something else catastrophic were to occur I would not even know about it.  So after much sanding I added another layer of fillet material and got it smoothed out pretty well as you can see here:

Rear Compartment Fillets

Rear Compartment Fillets

Hull 'Glass Template

After finishing that job I decided to begin making templates for the fiberglass that will cover the bottom-inside of the hull.  Only one template is done so far.  As you can see, the fiberglass will lap up onto the sides and the bulkheads.  There will be an overlap of about 6" over the keelson at the bottom-center.  This will add a lot of strength--that section will have a double layer.  The fiberglass will also be overlapped above the floorboard joists.

The manual doesn't mention anything about making the templates, but I can't think of any better way to get the fiberglass cut to fit.  Laying it in there and cutting it would be much harder and would probably damage the cloth here and there.  The two sides of the hull are mirror images, so I will only have to make templates for one side, and then use them for both.

More Work on the Rudder

Last week I glued the rudder "cheeks" in place.  The cheeks reinforce the rudder at the point where the tiller will be applying side forces.  You can see the slot for the tiller--wish I could add an arrow pointing to it, but I think it's obvious.

Rudder and Tiller

Here's a shot of the rudder with the tiller in its slot.  I have done most of the sanding on the rudder--a little more and the fiberglassing can begin.  Fiberglass will be applied below the cheeks and down the rudder sides, and then curve out onto the bottom plate.

Bottom Plate Fillet

In this closer shot of the fillet you can see a few lighter areas where I added fairing compound to any low spots.  This joint will be under a lot of pressure under sail and I want to make sure the fiberglass has an even, smoothly-curved surface to adhere to.  It is suggested in the manual that the bottom plate can be used as a step for boarding the boat, but I'm a little leery of that idea.

Wetting-out Coat, Side One

This morning I added fiberglass cloth to one side of the rudder and applied the "wetting-out" epoxy coat.  The wetting-out coat is to make sure that all the cloth is evenly "wetted" and that there are no spots that are starved for epoxy or that have too much epoxy.  I stood the rudder up temporarily to apply epoxy to the bottom plate.

I absolutely have to apply the next coat (fill coat) before the wetting-out coat has a chance to harden.  It can no longer be sticky, but must still be "rubbery."  This will happen in about eight hours or so.  The fill coat must be applied at that time to ensure a good chemical bond.  Chemical bonding is best, but a mechanical bond can also be achieved by sanding first.  In this case, though, sanding would damage the fiberglass cloth, which is barely below the surface of the epoxy. So it is imperative that I apply the fill coat at the proper time.   The third (gloss) coat can be applied after the fill coat cures (with sanding) but to get the best possible adhesion I will also try to apply it when I can still get a chemical bond.

It's hard to tell from this shot, but on what is at the moment the upper left corner of the bottom plate, the fiberglass cloth does not quite reach the corner, so I added a little patch.  I'll correct the template before I cut the 'glass for the other side.  Also you can see some black streaks where I got Magic Marker ink on the cloth that was applied to rudder.  I'll have to be more careful about that in future, but it does not matter here because I do not plan on a "bright finish," i.e., it will be painted instead of varnished.

Fillets Fixed, Building Rudder

I retired Oct. 10 so am finding more time to get some work done on the boat.  I finished chiseling and sanding the bad fillets and have now covered them over with new fillets.

You may remember from my previous post that I had applied the fillets when it was too warm and I was unable to smooth them out before they set.  I chipped and sanded out the bad spots and re-covered the fillets--this is a huge improvement--not as good as some I have seen in other blogs, but they will serve the purpose of both strengthening the joint and allowing the fiberglass cloth, to be applied later, a smooth curve to bend around.

Yesterday I began building the rudder, which seems fairly simple, except that it is tapered from the front to the back, but not at the top where the tiller will slot in.

The rudder consists of two sheets of plywood with wood "blocking" separating them.  The wider blocking at the top of the picture is 3/4" thick; the bottom blocking (to the left) tapers from 3/4" at the front to 1/4" thick at the rear of the rudder.  The  vertical blocking is tapered from 3/8" to 1/4" all along its length.  The more complicated part is the "triangular" block, which has a compound taper from 1/4" to 3/4", so that it is supposed to be a full 3/4" thick all along the edge that butts to the wide blocking.  I was a little over-zealous with my sanding so the triangular block is a little too thin at the bottom edge.  So it does not make good contact with the plywood there, but only for less than 1/2", and I am filling the gap with thickened epoxy so I don't think it will cause a problem.

Here the blocks are glued and clamped (the wider block at the top was glued yesterday).

And here is a closer shot of the compound-taper area clamping on the triangular block.  You can see the gap, but again it is very narrow and I am going to fill it. The block is in full contact with the plywood from the less than 1/2" to the top.   I clamped blocks of wood on the outside top and bottom to keep the triangular blocking in place and help the plywood conform to the curve.  At the top right you can barely make out the slot where the tiller will fit.  Another sheet of plywood will be glued to the top after these parts cure.

A "Not So Fun" Job

In an earlier post I talked about the weather being relatively cool and deciding to do some filleting work, which was a disaster.  More about that later.  The fillets are thickened epoxy used to round or soften any corners in the hull so the fiberglass cloth has a smooth curve to bend around.  It will not adhere well at all to sharp corners.  These fillets have to be as smooth as possible, not only for appearances, but because any bumps or voids will leave a "bubble" under the fiberglass causing a weak spot.  Weak spots, especially in boat hulls that are going to be bouncing around on a trailer, can be disastrous.

On some of the fillets I was at least able to do the initial smoothing and today I chiseled away some of the roughest areas on those.  After filling in a few low areas I should be able to sand them smooth enough at this point.

A not too bad fillet with the worst areas chiseled off--ready for sanding

There were one or two particularly bad areas where the epoxy started hardening before I could even start to smooth it out.

Very bad fillet, most of which has been chiseled away

 It is hard to tell from the picture, but in this case I have chipped most of the fillet away.  It will be sanded and a new fillet put in its place.  I'll post the results when I am able to get the job done.

The way the fillets are supposed to be done is the thickened epoxy is laid in, then smoothed and sculpted with a flat, rounded stick to get it as close as possible to the finished shape.  Then any spills and excess material are cleaned up with a putty knife.   After an hour or two, depending on the temperature, the fillet has started to gel, but is still malleable.  At this point the final smoothing and shaping is done with a gloved finger dipped in alcohol.  This can be done very nicely if the temperature is anywhere between 60 and 77 or so degrees F.

According to the epoxy manufacturer's literature, at 77 degrees the pot life of their resin, using slow hardener, is 23 minutes.  That's how long you have to spread the epoxy before it becomes unworkable.  What they refer to as "thin film set," where the epoxy feels fully hardened but is not yet cured is 5 hours at 77 degrees.  Full cure at this temperature takes 5 days.  So, at that temperature it is best to wait about two hours before the final smoothing.

Again according to manufacturer literature, at 86 degrees the pot life is about 17 minutes, thin film set (TFS) occurs at about 3 hours, 45 minutes, and full cure takes 3.75 days.  At 95 degrees pot life is 11 1/2 minutes and TFS is at 2 1/2 hours.

So to me this means I should have had at least an hour to an hour and a half before the epoxy became unworkable.  That tuned out not to be the case.  As I said, most of the fillets from that "pot" only gave me time for initial smoothing and the last fillets didn't even give me time for that.  I would estimate the actual pot life at about 5 or 6 minutes and the TFS time at the end of pot life at about one more minute.  The temperature when I started the project was 85 and I don't think it climbed above 87 before I was finished.

So what went wrong?  One possibility is that I accidentally added too much hardener.  But according to the manufacturer, this does not make the epoxy cure any faster, but can make it weaker.  As I learned today when chipping away at it, it was definitely not any weaker!  So I don't think that was it.

One response to my previous post was that epoxy starts to become unpredictable above 80 or so degrees, meaning I guess I can't trust the literature completely.  So, one more lesson learned the hard way.  If I remember all these lessons my next boat will be perfect!