putting a lid on it

Our original fridge had two lids side by side. There was an air gap between the lids so there was never any reasonable way to seal the lids. The lids also were held open by those collapsible springs that always seem to collapse when my head or fingers were in the way. So we decided to build a new lid and ledge for the lid to sit on.

The original lid was covered in a laminate that matched the galley counter top. We stood no chance of finding a match for that laminate and were not going to re-laminate the entire galley. Instead, we decided to make the fridge lid out of a butcher block material. We found a eucalyptus butcher block counter top material from Wood Welded. It was not cheap but looks pretty cool and matches the teak interior well enough. We could only get the butcher block in 24"x36" sections - which cost $200 - so we made sure to use up the off cuts. I made a matching cutting block that drops into the sink.




The matching cutting board built from the off cuts from the fridge lid.

The R-value of hard wood is negligible so we had to insulate the underside of the lid. I used the same extruded polystyrene (XPS) insulation that I insulated the fridge with. XPS (or blue board) foam cuts and shapes really well. I was able to shape a reasonably complex piece out of the foam. After getting the shape I wanted, I fiberglassed over the foam with 10 oz. cloth.


The blue board insulation cut down to the shape of the lid insulation. The piece of foam that's cut out is where the gas spring attaches to the lid insulation. I dropped some marine ply in there so the screws were going into wood, not foam.


After fiberglassing and fixing some sanding mistakes with thickened epoxy. Our fridge is composed of approximately 35% thickened epoxy.

We also had to build a new ledge for the lid to rest on. Our new lid was a different depth than the original and I had cut away the original lid ledge in the early days of this project. I built the lid ledge with the same process as the lid insulation. I added a few more layers of fiberglass on the lid ledge since it had to withstand the weight of the lid and whatever else I drop on it.


Assembling the foam to create the lid ledge.


Fiberglassing the lid ledge.


Dry fitting the ledge along with the freezer bin.

Both the lid insulation and lid ledge were finished the same way I finished the interior of our fridge box. I mixed West Systems epoxy along with a white pigment and coated the bejeezus out of both pieces. After the 10+ coats of epoxy cured, I faired the surface down and sanded it smooth. Then I wet sanded it with every grit of paper I could find between 400 and 1200 grit. Then hit the pieces with rubbing compound followed by 3M Glaze and a shot of carnuba wax.


Working on the epoxy finish.



The last piece of the lid puzzle was how to hold up this lid that weighs 20lbs without dropping it on my fingers or head. I installed a gas spring on the lid to give an assist in lifting the lid and keeping it open while I rummage through the bottom of the fridge for the just the right can of beer. Calculating the dimensions of the gas spring was a bit more complicated than I originally planned on. It involved trigonometry, Excel spreadsheets, and a dash of wild ass guesses. In the end, the spring I used worked great. It lifts the lid with virtually no effort, holds it open, and lets you effortlessly close the lid.




The gas spring attachment to the lid insulation.


The gas spring attachment to the fridge box.


The lid insulation.


Actual food actually being cooled by our actually operational fridge!

I still haven't put a gasket on the lid. That's on my list, just haven't gotten to it yet. I will also add a blog shortly on the refrigeration system we chose and how we installed it. Phew, good times right?

fridge box construction

(Boat nerd disclaimer - this blog post is going to be boring. It's mostly about what I did to build the box liner, where I screwed up, and how I fixed what I did wrong in the first place. If you want to know how to build a fridge, read on. If you could give a crap about building a fridge, here's some kittens singing Led Zeppelin.)

I thought constructing the box for the fridge interior would be messy and smelly and itchy and fairly time consuming. I underestimated how much by orders of magnitude. As a caveat: this was my first fiberglassing project. Coming into this part of the fridge project, everything I knew about how to fiberglass I learned on the internet. In articles on the internet, it looks pretty straightforward. Those articles always have some guy in snappy coveralls, safety glasses, safety respirator and safety gloves without a single speck of resin in his hair or on his elbows or up his nose. Those articles can kiss my ass.

Box Construction

I used 1/2" marine ply to build out the walls of the box. I had visions of the wood slowly turning into mush over the years so after cutting the pieces out and dry fitting them, I coated the individual pieces in epoxy. Before installing the box walls, I put in a moisture barrier between the box and insulation. I chose Reflectix insulation sealed with foil tape. In areas where the insulation didn't mate perfectly with the marine ply box walls, the Reflectix gave me some wiggle room to compress it. I wanted to avoid any air gaps right next to the box walls where condensation could build and introduce moisture into the insulation.

I then installed the epoxied box walls. I soon learned that the void created by the insulation resulted in a space comprised of not a single 90 degree angle. Because the Reflectix had some give to it, I was able to get the walls into something resembling plumb. I did have to brace the walls at a few spots where the insulation behind them wanted to bow the walls out.

After bracing the walls, I screwed the walls to the aluminum angle iron I installed underneath the counter top. Then I spent a frustrating and f-bomb filled couple of hours filleting the seams with thickened epoxy will hanging upside down and working around the braces I installed. The take-away lesson seemed to be that I was too stingy on the epoxy filler and should have thickened the mixture more than I had (I used mayonnaise consistency, should have used peanut butter consistency). I was using West Systems Low Density fairing filler which is fortunately easily sandable and results in a pretty forgiving material. In the end, I got the fillets installed but spent another few f-bomb filled hours sanding down the sloppy results.

Fiberglassing

Next up was the actual fiberglassing. This the point that I learned fiberglass cloth's natural tendency to unravel. It will unravel when you try to coat it with epoxy. It will unravel when you cut it. It will start unraveling you pull the scissors out. I gave one piece a sideways glance and the next thing I knew, it turned into a pile of unrelated fibers. This meant that when I wet out the cloth I applied to the box walls, I had strings dangling off the seams all over the place. These strings combine with the resin to turn into sticky, adhesive epoxy boogers. Grab one to get it out of the layup and it will unravel seven or eight other ones. I finally just ended up leaving the errant strings in place and sanded them down after the resin cured.

I added fiberglass to the box interior both to waterproof the wood but to also give the interior seams strength. I used one or two layers of 10oz. cloth on the walls themselves and three or four layers in the seams, particularly in the floor. All these overlapping layups resulted in a pretty lumpy finish, especially in the floor. I mixed up some more thickened epoxy and liberally slathered it all over the place. I poured a thick covering on the floor and let it self level. This gave me a layer I could fair without grinding away all the strengthening layers I put in place at the seams.

After everything cured, I washed down the walls with scotchbrite and water to remove the blush (I never saw any but read that West Systems epoxy blushes so I did it anyways). I then went to work on it with an orbital sander and 60 grit discs. As I got closer to fair, I moved up to 80 and then 100 grit discs. I discovered that epoxy + fiberglass is pretty workable material. After all the lumps and drips in the original layup, I was able to fair it all out pretty smooth.

Finish

Here's where I went off the reservation a bit. I was determined to find a paintable, food safe, impact resistant finish for the interior walls. I scoured the internet for such a thing. I asked the folks at the local fiberglass shop. I asked at the local chandlery. I hit up the sailing and cruising forums. I even hit up the boat refrigeration forum (talk about a niche site). No one had an answer for me.

So I fell back to a default position that I had a sinking feeling was not going to go well. I chose to use epoxy but add a white pigment to it. I didn't choose this because I thought it would be the easiest or best solution. I chose it because I never could come up with a better idea. Pigmented epoxy has any number of problems in this application but I'll give you the greatest hits:

• Epoxy is a two part solution that requires some healthy mixing. That healthy mixing introduces air bubbles which will lovingly transfer into your finish. When they pop, the surface looks cratered and pock marked. I've tried using a blowtorch to knock out the bubbles with limited success (and unlimited possibility of burning our boat to the waterline). I also tried misting denatured alcohol on the surface (I was smart enough to not try this at the same time as the blowtorch trick) which took care of the really small bubbles but didn't help with the large bubbles that surface after an hour or so.
• The liquid carrier for white pigment is actually just resin. Which means if you add too much pigment, you can throw the resin/hardener ratio off and the epoxy will never cure. So you have to be very careful about how much pigment you add. Which means each coat you add doesn't have much coverage for the colors behind it. Which means you have to add 5 or 6 coats in order to produce a solid white color.
• You have about a 45 minute window about four hours after you apply a coat to apply the next coat. When you need 5 or 6 coats, well... do the math. It makes for an ugly Monday morning after rolling epoxy at 4AM.
• Epoxy has so much viscosity that it can't help but sag or run on a vertical surface. I could also never get it to self level so my attempts at rolling and tipping resulted in seeing all the brush strokes. "Why didn't you cut the epoxy with some thinner?" asks everybody I mention this to. Because the 5 or 6 coats I had to add would have turned into many, many more.

In the end, I chose to add a ton of coats of sorta messy epoxy (I believe I counted 10 coats across two different sessions) and then work it down into something decent looking. I learned from surf board building forums (click here for the coolest wood & squid surfboard you'll see all day) that you can build up a nice looking gloss with epoxy. Here's what I did to get a glossy finish from a very messy epoxy application:

• Knocked down all the drips and sags with 80 grit
• Faired surface and smoothed out pock marks with 100 grit
• Further sanding with 220 grit and then 320 grit
• Wet sanded with 400 grit
• Wet sanded with 600 grit
• Wet sanded with 800 grit
• Wet sanded with 1000 grit
• Wet sanded with 1200 grit
• Took a buffing wheel attachment on a drill and worked a polishing compound into the surface
• Washed off the polishing compound and had a beer

The end result? Not bad. I sanded through the coverage in a few spots so you can see shadows of the colors behind the white epoxy but mostly in areas you can't see so I don't care. The rest of it came out pretty nice. It also results in a glossy surface that will be much easier to clean than if I had left it matte.







The last piece of the box construction itself was to add a removable bottom on the floor so any foodstuff doesn't end up sitting in water at the bottom the fridge. I order a simple sheet of polycarbonate from Tapp Plastics, drilled drain holes in it, rounded the edges, and drilled a couple finger sized holes to be able to remove it. The final test of the box construction was to check the results were true to the original design. Is the height of the "beer can well" the exact height of a can of beer? See for yourself:





This part took forever partially because we took the summer off to put on a new bowsprit and windlass (long story, I'll tell you later) and partially because it was just way harder than I thought.

Next up? How to build a fridge lid. I know, I can hardly wait!

fridge insulation

I figured it would take me one weekend to install the insulation for the fridge box. Possibly two weekends if something went horribly wrong. That was back in February. I just finished the insulation install Friday. By my count, that task took two weekends plus or minus 8 weekends. Granted, I really wasn't working on the fridge the whole time. There was a lot of downtime this winter due to weather and generally lack of motivation (at least two of those weekends back in February were devoted to The Wire marathons).

My original plan was to install 2" XPS (extruded polystyrene) sheets underneath the fridge box and against the hull. XPS is good at resisting water entry but has a slightly lower R value of R5. I planned on using polyisocyanurate on the inboard walls where I had less space for insulation. Polyiso is rated at R6.5 but it doesn't deal well with moisture. It also doesn't handle being cut and manipulated nearly as well as it tends to crumble. I decided to use it only on the inboard facing wall next to the sink, mostly because it proved to be a real pain in the ass. The rest of the walls in the fridge got the XPS treatment. Against the curve of the hull above the waterline where the sun hits the hull, I glued Reflectix onto the outward face of XPS boards and left about a one inch air gap between the hull and insulation. The idea is to reflect radiative heat transfer from the sun hitting the hull. I have no idea if this will make a difference but given the difficulty of matching rectilinear foam boards with the curve of the hull, I was going to end up with an air gap anyways, so I thought I'd take advantage of it.


XPS sheets being installed in the floor. The pink and blue sheets are both XPS, just different manufacturers.


Polyisocyanurate insulation installed on the inboard wall.


The reflectix insulation installed against the hull.

Given the oppressive amounts of cold beer and ice I plan on storing in this fridge box, I needed some structure to support the weight of the box. My goal was to provide some beefy structure without having to cut out much insulation. I ended up using 2" aluminum angle iron mounted longitudinally under the fridge box. I through-bolted epoxy covered brackets on the fore and aft cabinet walls and laid the aluminum beam on top of those brackets to sit flush with a layer of insulation. I used the same material mounted under the countertop to support the vertical walls of the fridge box.


Longitudinal aluminum angle iron support.

My construction process went a little something like this:

• First, I installed an epoxy covered wood standoff on the cabinet floor so if any moisture got into the cabinet, the insulation would not sit in it. I drilled a few weep holes from the floor into the bilge so water couldn't build up.
• I put a layer of builder's plastic against the hull. The idea was if the deck to hull joint or deck stanchion started leaking into the cabinet, it wouldn't penetrate the insulation. I didn't encapsulate the entire insulation in a vapor barrier because I've read that all that does is trap moisture inside the insulation. A more accurate way of stating that would be: I encapsulated the entire insulation in a vapor barrier THEN I read that all that does is trap moisture inside the insulation THEN I spent a weekend removing the vapor barrier and three tubes of silicon I used to hang the vapor barrier.
• The only option we had to run wiring for the compressor install is currently crammed with wiring and would require removing some wire to accomodate the compressor wiring. Given that I had 9" to 11" of space for insulation against the hull near the top of the box, I decided to install a wiring conduit in the back of the box. I'm not wild about this choice. Cutting the insulation around the conduit was a giant pain.
• Cut and dry fit foam for a single wall. This is a very iterative process when you have to work through the opening (oh, this perfectly cut piece of foam doesn't fit inside the opening) and when you have a complex curve and fridge box that steps down (oh, this perfectly cut piece of foam doesn't actually fit the space it's supposed to fit in).
• Once I got all the pieces cut and dry fit (and labeled, all the pieces start to look the same after a while), I installed the insulation for that wall. I caulked every seam and joint with silicon to make sure that there was no air passage through the insulation. Every gap larger than 1/8", got injected with spray foam. Here's a tip with spray foam: wear latex gloves and a long sleeve shirt when using this crap. You'll think you're being all super careful and cautious and then your wife will point and guffaw at the cabbage-sized glob of spray foam hanging on your elbow of which portions will remain stuck to you three days later.
• Once the spray foam cured, I'd trim it back down and coat any exposed spray foam with silicon. Spray foam doesn't like moisture either. One other note about spray foam: it cures with some pretty large air bubbles in it so don't depend on it for any large voids. I relied on it more as way to prevent air passage, rather than proper insulation.
• Once the wall was done, I moved on to the next wall. Lather, rinse, repeat.
• After all the insulation was in place, I caulked all the seams a final time with silicon to make sure no air was going to leak through the box.

The end result of all this foam cutting and fitting and caulking:

• 9" of XPS insulation below the fridge box.
• Anywhere from 5" to about 11" of XPS insulation against the hull.
• 4" of XPS insulation on the aft cabinet wall.
• 6" of XPS insulation on the forward cabinet wall.
• 3" of polyisocyanurate insulation plus 3/4" of layers of reflectix because I couldn't find 3/4" foam boards.

Bare fridge cabinet.


Standoff installed.


Plastic installed against the hull.


Floor insulation complete along with brackets for longitudinal support beam.


Aluminum angle iron acting as a support beam.


Inboard wall with polyiso insulation and then covered with Reflectix. You can also see the aluminum angle iron used as a support for the vertical fridge walls.


Forward wall complete.


Aft wall complete.


This was all the foam I used in just the top half of the outboard wall against the hull.


I think I cut about 30 individual pieces of foam to fit the outboard wall.


Insulation is DONE!




Sizing some of the foam pieces.


Our disaster of a cockpit during construction. I did all the foam cutting in our cockpit. Any attempt to cut foam on the dock ended up with foam particles in the water and that's no bueno.

If you feel that you just haven't gotten enough pictures of pink and blue foam, I took an extensive amount of photos and uploaded them here.

fridge box design

(Boat nerd post. You've been warned...)

Since we're employed and functioning members of polite society, we only have weekends to really get anything done on this fridge project. And since all work and no play makes Jack a dull boy, we keep scheduling our weekends with things that are more fun than building a fridge (like drinking wine and hanging with friends we haven't seen in ages). We should be done with this project sometime around Christmas. 2012.

I have been working on the design of the fridge box (click here for the plans I drew up for the fridge box). I don't really like fridge interiors that follow the curve of the hull. Ours was like that and it was *impossible* to have any sort of organization to the food as it all eventually ends up in a big pile. It felt like I was rumaging through a dumpster looking for something good to eat. So on the side of the fridge box next to the hull, we'll step the box down giving us a useful shelf. The lowest area of the fridge box, we are calling the "beer can well". It will be the depth of a can of beer, allowing us to pack the bottom of the fridge with cans. This guarantees we will always have something cold to drink, makes a flat space to load the rest of the food in the fridge onto and provides a sort of alcoholic holding plate to store negative BTU's between compressor cycles.



We also want to make sure that at the closest point to the hull, the box is at least six inches away. This should give us a good buffer of insulation so when the hull heats up from the sun, the compressor shouldn't have to work quite so hard. Most of the hull above the waterline will have between 8 and 10 inches of insulation protecting the fridge box.

At the floor of the box, I am going to put in epoxy-coated 1"x1" firring strips and then an epoxy coated piece of 1/2" marine ply. This will keep the insulation off the floor of the box in case any water does penetrate. There is a stanchion on deck that if it leaked, would leak into the fridge box. I'll probably provide a tiny drain hole into the bilge so water can't build up. All of the insulation will be encapsulated in overlapping sheets of builders plastic.

For insulation in the bottom of the box, I'll use 1" extruded polystyrene foam boards (XPS). Their R factor is a little lower at R5 but they are more resistant to water entry than other foams. Since I'm replacing a huge fridge box, I'll end up with around 13 inches of insulation at the bottom of the box so I'm not really concerned about R value for this insulation. I'm going to use XPS for the insulation against the hull since that's another area that's more likely to have water intrusion.

For insulation on the inboard walls, I'll only have about 4" of insulation to work with. I'm going to use polyisocyanurate there since it has a higher R value (R6.5). The downside to polyiso is that isn't as moisture resistant as polystyrene. However, it is lined on either side with aluminum foil. Once I cut the pieces, I'll epoxy coat the ends. Along with encapsulating it in 6mil builders plastic, that should keep the moisture out.

The existing fridge lids are just 2" of wood, held open by collapsible springs of death. When you have your head stuck way down in the box and accidentally touch one of the springs that hold the lids open, they come crashing down like Vlade Divac in the paint and 8lbs of solid wood lands squarely on the back of your head. Ask me how I know. We'll be replacing these evil contraptions with gas springs. I'm also going to add at least an inch of insulation to the bottom of the lids to give it a little better R factor.

In the end, we will have reduced our 11 cu.ft. fridge/freezer down to a well insulated 4 cu.ft. of fridge space and 0.6 cu.ft. of freezer space.


We got a rare sunny day that lit the hull enough to figure out where the waterline was. We marked it for posterity.


Our fridge box mockup including our highly specialized measuring equipment.

tearing out the fridge box

When we bought Hello World, she came with an AC powered compressor so large, we suspect it was designed to run freezers in a morgue. All that cooling capacity came at the cost of our batteries. Running the fridge would pull 70 amps DC out of our battery bank. When I tell other cruisers that they always say: "you mean 70 amp hours per day, right?" No, 70 amp hours per hour. About 10 times the electrical draw of other marine refrigeration units on boats our size.

So the compressor had to go.

The fridge box itself was also massive. Given all that interior space to cool combined with the mediocre insulation and the fridge box had to go, too.

So last weekend we commenced to ripping out the existing fridge box. In order to keep destruction to a minimum, we ponied up an exorbitant amount of cash for a Fein Multimaster. This thing made short work of cutting out all the refrigerant lines and fiberglass liner. It's scraper blade went through the spray foam insulation like a hot knife through butter.

When we pulled the foam out, we found alot of moisture in the bottom of the insulation. It probably wasn't doing much for us so we're happy we pulled it out. We also found a 1" x 15" void against the hull which must have been some giant air bubble when they poured the two-part foam at the Caliber factory.

It took a total of 3 days to rip out the previous fridge box, including tenting the boat interior and suiting up in tyvek suits to cut out the fiberglass.


While in Mexico, we got desperate for cold beer so we lined the freezer portion of the box with polystyrene foam sheets and glued them together with spray foam. Hillbilly refrigeration.


New toy!


The divider partition torn out.


Getting ready to chainsaw the fiberglass liner.


Christy getting the foam out of the bottom of the box.


I told you it was a big fridge box.


The void in the insulation next to the hull.


5 inches of insulation on the inboard side next to the sink.


All cleaned out.


Marking the waterline.