# Chartplotter on a Swing Arm



## mstern (May 26, 2002)

I've had various GPS's for my Oday 23 since I bought her almost 20 years ago. They've all had two things in common: they were all hand-held units, and I mounted them all on the bulkhead in the cockpit, facing the stern. This kept them visible to the helm, but because the boat is fairly small, they were also somewhat vulnerable to being kicked or jostled. And if someone were sitting near the bulkhead, the unit would be hard to see for anyone else.

I decided to bite the bullet a few years ago, and I bought a real chartplotter/fishfinder at the Defender spring sale; the thing was practically half price, and included a Navionics chip with the latest charts. I decided to mount it on the bulkhead, near where I had mounted the hand-helds before. It looked great, but it was a mistake. The chartplotter, being bigger than the hand helds, was an even bigger target for errant feet, knees and elbows. And despite the claims of Lowrance, it was clear that the mount and cable weren't really robust enough to take the unit on and off after each trip.

So last fall, I decided to finally remedy the situation and mount the unit on a swing arm in the companionway. I measured, and found an arm unit on Amazon that fit the bill (cost, about $15). The inner wall of the cabin was very thin fiberglass, so I had to glue a piece of wood to the interior of the wall for a secure mount (fortunately, there was already a large access hole drilled nearby by the previous owner to mount a now-gone speedo dial), and the whole thing went off without a hitch. Here are a couple of photos, showing the unit in the companionway, and folded into the cabin. You can see where the unit used to be mounted on the cockpit bulkhead on the left; I am going to be removing the teak pieces and covering the hole with starboard.


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## WinterRiver (Oct 20, 2006)

Nicely done. You should add this to the low bucks projects thread


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## capta (Jun 27, 2011)

Why wouldn't you flush mount it on the bulkhead?


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## Markwesti (Jan 1, 2013)

Fine job mstern , your boat brings back some fond memories . A O'Day 23 was our first boat . I would do the same thing with our "new" boat but there is a port light in the bulkhead so I made a clamp and it sits nicely in the port light and the cable goes thru and the electric switch panel is right under neath on the inside and it has a fem plug and when we are done it all comes off . . Another nice thing about having it mounted like you do I have found is that when you change sides you can tilt the screen for better viewing . Any more pics of your boat ?


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## SHNOOL (Jun 7, 2007)

I've often wondered if mounting all my instruments would be better this way... either way I like how it looks! Thanks for the idea!


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## Faster (Sep 13, 2005)

Nice.. what material is the mount made of? Do you expect it to stand up in the marine environment?


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## mstern (May 26, 2002)

capta said:


> Why wouldn't you flush mount it on the bulkhead?


Two reasons: It seemed like an awfully big commitment to this particular piece of equipment; the hole needed by this unit would be very big (compared to the overall size of the bulkhead), and it would mean that I was wedded to this unit forever -- or that I would at least have to face big issues in repairing the hole if I wanted to change.

That and it was too much work to mount it that way. A lot easier to use the existing hole to run the wires and just screw the provided mount to some teak outlet plates. I'm all about easy.


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## mstern (May 26, 2002)

Faster said:


> Nice.. what material is the mount made of? Do you expect it to stand up in the marine environment?


It's steel. My guess is cheap Chinese steel. I don't know how it will stand up in the salt marine environment, but for the difference in price between this unit and the RAM products I was comparing it to, I can replace this thing 10 times before I am out any money. Let's hope that a regular spritz to the joints with WD-40 keeps us in business.

btw, the GPS mounts to a Lowrence proprietary swivel mount, which I had to fasten to a piece of starboard, which in turn, is connected to the swing arm. You can sort of see the white piece of starboard in the photos. At least I know that won't rust.


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## mstern (May 26, 2002)

Markwesti said:


> . Any more pics of your boat ?


Here's a couple that I found.


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## roverhi (Dec 19, 2013)

capta said:


> Why wouldn't you flush mount it on the bulkhead?


There were several reasons I mounted the plotter on a Ram mount swing arm for my boat. First was I didn't want to cut a big hole in the cabin side for an instrument that would be an antique in a short period of time and possibly prone to an early demise. Just filled holes in the cabin side where an old log and depth sounder that were KIA had been mounted. Didn't want to have to do that with an even larger puka. 2. These plotters are hard to see in direct sunlight. Way easier to see in the companionway out of direct sun especially if the sliding hatch is closed. 3. With the ram mount, can swing the plotter inside to so I can see it from down below. On long passages that's a big plus especially if you have radar and you keep watch from inside. 4. Installed the ram mount on the side of a mahogany box fastened to the inside of the cabin that housed my electric panel and attendant wiring. Made it super clean and easy to run the antenna lead and power to the unit.


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## jeremiahbltz2 (Mar 30, 2017)

mstern said:


> Let's hope that a regular spritz to the joints with WD-40 keeps us in business.


I don't know much about anything, but I do know a bit about WD-40.

If you put a drop or two of machine oil on the joints after you WD-40, it'll last a long longer and you can do it a lot less frequently. WD-40 is great at driving out water (that's what it's made for), and good at freeing a stuck connection, but it's not a lubricant. The oils in it are very volatile, and literally evaporate away. If you put a drop of oil in, the WD-40 carries it into the joint. It works magnificently.


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## mstern (May 26, 2002)

jeremiahbltz2 said:


> I don't know much about anything, but I do know a bit about WD-40.
> 
> If you put a drop or two of machine oil on the joints after you WD-40, it'll last a long longer and you can do it a lot less frequently. WD-40 is great at driving out water (that's what it's made for), and good at freeing a stuck connection, but it's not a lubricant. The oils in it are very volatile, and literally evaporate away. If you put a drop of oil in, the WD-40 carries it into the joint. It works magnificently.


I learn me something new every day. Thanks.


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## Jeff_H (Feb 26, 2000)

Nice solution and installation. Its always nice to see how people handle these issues.

On a prior boat with a similar issue, I made a partial companionway slide (painted 1x4 Fir) and mounted my depth sounder on that short hatch slide. When I wanted the depth sounder, I just dropped the slide into place.

I protected the back of the instrument with a plastic butter container. The lid was screwed to the back of the slide, and the plastic tub was snapped into the lid. I chose a butter tub instead of a margarine tub since there was a brand of butter that had a white rather than a yellow tub. 
On another boat I made an arm that was simply hinged off the bulkhead with a second arm hinged off the top of it so it could lie flat against the bulkhead with the instrument facing into the cabin. That one was made from an old plastic cutting board.

Although this is a different installation problem, I wrestled with how to mount my chart plotter on my current boat. In this case, I wanted it close to wheel so I could see it and I also wanted to be able to see it from the helm on either side of the cockpit or from behind the wheel.

I came up with this design for a binnacle mounted turntable which allows me to rotate the unit so I can see it from either side or astern and/or the face of the screen so is out of the direct sunlight. It is made from Starboard, a carriage bolt and a four screws. There is a knob on the bottom also made from starboard that I cut out with a hole saw, and chiseled a recess for the nut that goes onto the carriage bolt so the turntable can be loosened and tightened. It has worked really well and has not required any new holes except for the cable run.


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## WolfmanBob (Apr 4, 2016)

Looks great, mstern. I was thinking of doing something similar. I use a tablet for a chartplotter. Can you provide a link to the swing arm you chose?


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## Minnesail (Feb 19, 2013)

Thanks for posting pictures, I would also like to do something similar on my little boat. I thought about mounting it on the bulkhead but then it would be obscured when someone was sitting there (and it'd be a big hole to cut). I also like the idea of the chartplotter being inside when not in use.


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## mstern (May 26, 2002)

WolfmanBob said:


> Looks great, mstern. I was thinking of doing something similar. I use a tablet for a chartplotter. Can you provide a link to the swing arm you chose?


I guess I shouldn't be surprised that Amazon kept this information about my order on file. Here is the unit.

https://www.amazon.com/gp/product/B01BCUM766/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1


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## FreeAgent (Apr 19, 2017)

mstern said:


> I guess I shouldn't be surprised that Amazon kept this information about my order on file. Here is the unit.
> 
> https://www.amazon.com/gp/product/B01BCUM766/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1


Back in the 70's our depthsounders were the flasher type and were just about same size as your chartplotter. We devised similar sorts of swinging arms so sounder was visible in companionway. We never had chartplotters or Amazon or $12 swinging arms! We made the arms out of teak.

On a bit larger boat, we put an opening Beckson plastic port in the bulkhead and mounted our Loran C on the inside where it was visible from cockpit and could be accessed.

By the way - Nice job and perfect for your boat!


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## Mainah (Oct 5, 2011)

MStern,
What keeps the swing unit in place? Is there enough friction to hold it in place in a chop?
Thanks, it looks great.


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## mstern (May 26, 2002)

Mainah said:


> MStern,
> What keeps the swing unit in place? Is there enough friction to hold it in place in a chop?
> Thanks, it looks great.


Friction keeps the unit from swinging too freely. The arm is made to support heavy TVs, so the chartplotter is almost weightless for it. I haven't taken the boat out yet this season (my outboard won't start; that's another thread....), so I don't know how it will perform in a chop. It seems stiff enough, but we'll see soon (hopefully).


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## albrazzi (Oct 15, 2014)

Nice solution, my crew donated a small older unit and I made a swing from some scrap Mahogany clamped around the SS hand hold inside the companion way. Under way we swing it out just like yours. So when I bought a big one for the helm there's one for me and one for the crew.


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## Plumbean (Dec 17, 2009)

I just installed my new chart plotter on a double swing arm mount in the companionway. I mounted it so that if needed I can have the lower drop board in and the hatchway closed and still have access to the plotter. I used a RAM mount, which is expensive and was a lot larger than I expected from the photos on their site. At least you get what you pay for, as the mount seems very robust and well made. So far the setup has worked great.


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