Instrument pod modifications

Between jaunts out on the water sometimes there are things to do to Beetle; for instance, the run to Catalina turned up a list of 11 things that needed attention. Most are simply to get a part, such as a replacement 2-1/2 gallon white plastic bucket because a bucket split – that’s an easy one, a trip to Ace Hardware, a couple of holes drilled for the rope handle, and you’re done.

The big project following the visit to Catalina is modifying the on-deck instrument pod for purposes of installing a new/second Zeus3 7″ chart plotter/display in the pod. I bought the first Zeus3 early last year and it worked so well that I figured a second unit in the pod would bring a bunch of good information to the cockpit (AIS, cartography, radar, easier-to-read GPS performance data) that currently mostly requires going down to the nav station to look at. The addition took two weeks. Here’s how it went, mostly in pictures:

The instrument pod spans the companionway and has six B&G Network instrument displays. I had built the pod on a male mold using a fiberglass layup and epoxy to create a place for the instruments prior to Beetle’s first Singlehanded TransPac race. I spend a lot of time sitting in the companionway and having the instruments right there in front of me is handy. At that time I had not yet constructed the hard dodger therefore the pod needed to be strong enough to stand on as it was used rather as a lot as a foot brace and step to work on the mainsail – so the pod was made extra-strong. In this picture, years later, I’ve added the hard dodger which protects the pod and I’m experimenting with where the new B&G Zeus3 7″ chart plotter might fit. The first plotter came on board early 2020 when I found the Furuno chart plotter could no longer read the current Navionics cartography SD cards. Unfortunately the Zeus3 is taller than the pod and won’t fit, and sticking it on top of the pod looked silly and helped to block the view. Instead I moved the Zeus3 belowdecks to the nav station table to protect the unit from water and sun. But the new Zeus3 is going into the instrument pod – time to make some changes to the pod.
I used a Fein oscillating cutter to carefully trepan the top right section of the instrument pod, the goal being to preserve the rounded corners on the right and rear of the pod. Constructing radiused edges in fiberglass is not as easy as making flat plates, therefore I wanted to retain as much of the radiused housing areas as I could. The instrument does fit, there’s sufficient depth in the pod for cabling, and I cut short the front panel which is still wide enough to house four instrument displays. So far so good.

With clamps and some blocks of particularly straight & square wood I lifted the original top pod section 1-1/2 inches and clamped it in place. The goal is to line everything up, span gaps on the right and top/rear with new glasswork. I couldn’t just lift the pod’s top surface vertically as it would run into the hard dodger – so the top/rear takes on the angle of the dodger. At this point I was still thinking I could do all the work with the dodger in place – which turned out to be futile – the dodger had to be unbolted and removed, and to remove the dodger I had to pull the clutch banks. That added a bunch of work I was hoping to avoid.

With blue tape in place to protect the front panel mounting surfaces, I laminated on the extension to the right side and top/rear of the pod. Fiberglass does not laminate well suspended in air, so there’s a board on the right (with packing tape over it) that forms the mold on the right, and a second board covered in more packing tape that spans the gap at the rear to top of the pod. The old fiberglass has been beveled inside and outside to give the new glass a nice surface area for bonding – the bumps at the overlapping joint will be ground down later. By this pointI had moved the dodger out of the way to make room for working on the rear of the pod. Let the layup dry overnight and the image is what you get.
With the supports and moldwork removed the top of the pod stays in place and is quite strong. Next step is to create the ‘S’ curve inside-outside radius section to connect the raised pod surface back to the old top. Lots of tape is applied anywhere I do not want to change the surface by dripping epoxy on it – the time spent applying tape saves lots of time spent sanding later. Tape early, Tape often.
The mold/form for the ‘S’ curve is simple and inelegant – just some foam core trimmed with an X-acto knife to create the profile, with flat tooth picks hot-glued across the profile to support the wet layup. I tried to build something really nice using PVC pipes but that didn’t work – so the ‘S’ curve is going to have more fairing work than I’d wanted.
Here’s the form from inside the pod – at least the laminate went on mostly-square with good compression up against the underside of the pod’s old glasswork. I got strong, if not necessarily pretty, results on this pass. Wait overnight for epoxy to cure.
With the clamps removed the result looks pretty ugly. The rear corners of the raised portion are going to need a bunch of sanding/sculpting and additional glass, but at least I’ve got the basic structure in place – at this point I could stand on the instrument pod and while it flexes a touch it’s solid.
A round of sanding and it’s starting to look like an instrument pod again. I still need to add wood inserts to complete the flange the front panel attaches to – that’s why there’s lots of blue tape to protect the flange front surface from dripping resin.
Side view of the pod, makes it easy to see the angle the pod takes on as it rises to match the angle of the dodger.
After a couple of rounds of fairing the shape was looking ok so time to add a couple of layers glass to the outside and look at making the replacement front panel.
Outside glass on. The blue tape is protecting the original gel-coated top of the pod – I know I don’t want to sand those areas so tape them off and let the new layup continue onto the tape. The tape becomes a good guide to let you know when you’ve sanded down to the original surface – when the blue disappears you’re there.
New front panel being marked up. The instrument pod is hand-built (by me) so it’s not perfectly straight or square, close but not perfect. This makes it interesting to decide where centerline should be, the goal being to make the instruments *look* parallel to the pod even if they aren’t. Holes were cut out with a sabre saw and a plywood scrolling blade.
The first test fit was a lot of fun, I finally get to see what it will look like. The wiring required most of a day to carefully remove old wires, feed in new wires, crimping, installing a sealed water-tight ethernet router (connects the new display to the nav station display and the Halo24 radar), plus get the NMEA 0183 instrument network back in place alongside the new NMEA 2000 network. I really wanted to verify everything fit, turned on, and worked across the connections before getting into final finish.
The pod front panel is 1/4″ Joubert Okoume plywood, a very light nice marine plywood to work with. The plywood gets a layer of 6oz glass cloth front and back to stiffen the wood, protect it from water, and provide a good surface for the gelcoat. The cabin table with thick plastic sheeting taped in place made a convenient place to work.
Small wood blocks were spooged into place to span the gaps in the flange the front panel screws to. Learned quickly to make a cardboard profile template, trace that onto the wood, then cut out the wood with the sabre saw. They fit without a lot of effort.
Time to gelcoat and make it all look pretty. Gelcoat is too thick to brush on, so I use a small Paasche airbrush for the application. Gelcoat is nothing more than a slightly thickened polyester resin with a ton of tint added (white in my case) and I had part of a quart can left over from the bow re-coat project done earlier this year. The Paasche VL airbrush has a no. 5 tip that will pass a lot of material and works great when I thin the polyester with 50% styrene, add 3% MEKP catalyst, stir and run the brush at 50 PSI. I can get about 20ml of gelcoat through the brush before I have to dismantle the brush and soak it in acetone. Wait 45 minutes, repeat – many coats can be applied in one day. To have clearance to work I moved the dodger off the cabin top, tarped off the area with plastic sheeting, and just kept at it.
Polyester resins will not cure in the presence of air; to get the final coat to cure I spray on a film of PVA (polyvinyl alcohol), that’s the green tint in the picture. PVA dries by having the alcohol flash off and you get a thin vinyl film. That film dissolves in water (makes it easy to remove later, just use a sponge and a bucket of water), but you don’t want the evening’s dew to settle as that will dissolve the film as well. For overnight curing I wrapped the plastic sheeting loosely over the pod.
The finished pod.
Instruments installed, tested – everything works!
Dodger re-installed on the dock (another two days of cleaning, removing old sealant, prepping for new sealant, then running in a lot of bolts), and the pod set up for night sailing. The Zeus3 replaced two of the Network instruments – the Compass unit and the NAV unit. A nice feature of the Zeus3 is it can display four numbers simultaneously, and the numbers are large enough to easily read from the wheel at the back of the cockpit.

Time to go sailing!

– rob/beetle

2 responses to “Instrument pod modifications

  1. Once again I read every word and mentally spent all the hours and days you used to design, create, finish, test…..along with you. I guess I do know you well enough to know ” how” you do project.This was a design /installation classic and WOW Rob! It’s beautiful! The great news is that as you use the nav tools every day you will be reminded of your talent and omg extreme follow-through to exact these projects.

    I spoke of lexan window through bolts the other day…I held that wrench on the outside nuts as you turned and tightened the screws on 150 of them — yeh…..I was the girl on deck in dead of winter I know the exact number! ❤️

    I wondered when you would surface again….and here you are in your inimitable style–busy at the work at hand. Likewise over here in the organic food forest I’ve made great effort to plant more and more bee attractors and voilà ! FINALLY…OF the few honey bees around….some are coming to my garden now daily along with the two monarch butterflies I’ve watched busily chomping on the milkweed I have planted for them I love observing the truly thrilling natural responses to my efforts to save the insects. I was privy alas to the dying and death of a mole cricket who happened into my patio….a friend identified it for me. Do you know this one? I have 2 total pears this season 🥲 climate plus no pollinators but a huge tomato vine is finally productive recognize the ONION flower with wonderfully edible flowers and ensuing seeds! I don’t plant onions grill seeds🤪

    So here we are on land and sea,each doing the thing that makes our days so full! I’ll follow up Please do also –and remember….you did promise a visit next time you’re around up here. Hugs and happy seasonal changing days. The light is already different and soup is often in order.. Hugs blanche Ps the big bee attractor is African blue basil!! I grew rows of it on my farm for my own 3 bee hives…..the honey was complex, very dark, herbal, and spicy! Yes!! Really >

  2. Rock Island Email

    Wow…..what a hugh amount of work was required to redo the instrument pod…..and how impressive the results. You could have been a boat builder Rob.

    The pictures made the job all the more understandable. Thanks for sending.


    Sent from my iPad


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