Nav electronics replacement

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Jonathan Boright

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Apr 21, 2024, 10:48:18 AMApr 21
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Hi all, 
Apologies for the not-Pearson-specific question... but you all have such useful knowledge that I'm posting it here anyway.
I have a new-to-me P 26 (there's another thread from last fall with the details), and I'm looking to replace the electronics before splashing this summer.  What I'd like is depth, speed, and wind. I don't think that I need a chartplotter.... hoping to use an iPad or similar for that... but if I'm replacing the thru-hull transducers, I'd like them to be compatible with other equipment (like Chartplotters) if I decide to upgrade in the future.  
So, what I'm seeing online are the standard Raymarine, Garmin, or B&G products.   For example, here's a package that appears to have everything: 
So the question to you all is; are there products out there that I should avoid? either because the quality isn't there, the price too high, or the tech is old and will soon be obsolete (not upgradable)? Or, on the other hand, are there products that you recommend and have good experiences with?  ... tried and true?  
For use context, I'm sailing in Lake Champlain... mostly day sailing but hope to go on a few overnights too. 
Cheers and thanks!

Jon  

Last Resort

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Apr 22, 2024, 10:48:01 AMApr 22
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I stay away from Raymarine since all their stuff uses proprietary hook ups and wiring, and expensive.  I have all Garmin, but wouldn't do it again (search here for my rant on that).  B&G or Lowrance would be my choice if I had to do it all over again.  FYI, sailing with an iPad or such can be tricky, and one bad wave and it's wiped out.  Good Luck!

Jonathan Boright

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Apr 22, 2024, 11:22:13 AMApr 22
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Thanks LR!
…just the kind of perspective I was looking for. 
Cheers!
J


Jonathan Boright
bor...@isciences.com
Research Scientist
ISciences, LLC
126 College Street. Suite 330 (note new address)
Burlington, VT  05401
main: (802) 864-2999direct: (802) 448-7824


Water and Climate, Corporate Sustainability, Remote Sensing, Human Security


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Dave Cole

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Apr 22, 2024, 11:52:12 AMApr 22
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I have been using waterproof tablets for years for navigation.   
I first used a Sony waterproof tablet, and now a Galaxy Tab Active unit.
I usually have two tablets onboard plus my phone for backup.  

I have a bimini and it works fine under that.  Direct sunlight will wash out just about any display.
I have a Ram mount that is spring loaded and holds the tablet at the helm. 
It works great. 

If you look on Amazon, there are now at least a dozen waterproof tablets being sold now.

I would avoid a "hard" chartplotter.   The hardware will be supported by the manufacturer for a couple of years and then they will move on to the next
latest and greatest, leaving you holding the bag.  

 For depth, I have an old depth sounder that just fails to die.  
I have a knot meter but the zebra mussels keep clogging the sensing wheel, so GPS speed it is! 

Dave
10M #26



Guy Johnson

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Apr 23, 2024, 10:01:20 AMApr 23
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I have some preference for sensors that put out data directly on the NMEA 2000 bus. Many of the ray marine systems require an intermediate box to process the transducer signal. 

Guy
Puffin 10M #6

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Kobus Meyer

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Apr 23, 2024, 10:02:55 AMApr 23
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I have a whole suite of Raymarine products but I will never do that again. Also no more full Garmin or B&G system. Will cherry pick things like radar etc but no more expensive chart plotters. OpenCPN and Navioncs (or similar app) will do. 

I will build my open source system with select brand pieces like the Garmin Airmar transducer. Told a friend and heinstalled it and is very happy with it. 
If you add a NMEA 2000 wifi like the Yacht devices NMEA 2000 (which I have on my boat connecting to tablet and computer running OpenCPN). 


Hope that helps. 

Kobus Meyer
Pearson 365 - “Wind Sloth”
0.12 kts  Maximum, when threatened

Home Port - Kemah Tx

On Apr 21, 2024, at 08:48, Jonathan Boright <jbor...@gmail.com> wrote:

Hi all, 
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Jeff Griglack

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Apr 23, 2024, 10:33:16 AMApr 23
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Kobus,

I agree with you on building things up yourself, but a lot of people won't want to go through the work.  BTW, Airmar is a wholly owned subsidiary of Amphenol Corp., not Garmin.  You can buy from them directly and get tech support from them (and they're responsive and support their old products).  The (old) RayMarine speed/depth/temperature sensor is actually made by Airmar and set up to talk SeaTalk (no, not SeaTalk II which is essentially NMEA-2000).  They make these sensors for a lot of the navigation system manufacturers.

What are you running OpenCPN on?  The nice thing about this is that you can run it on an off the shelf laptop, if you want, or a dedicated board (like a Raspberry Pi board running Linux).  I have a couple of older laptops sitting around, so I can have backup systems available.

A couple of years ago, I picked up a Davis anemometer made for a household weather station.  I found a site with code for the Arduino board, but I pushed the whole thing to the background.  Recently, I have revived my project and modified the code a little. I want to feed this into Signal K and OpenCPN.

I have been using Navionics on an 8" tablet at the helm, but you can set up your OpenCPN system with a VPN and display it on a waterproof tablet at the helm.  That's not really much different from what I have seen for B&G or RayMarine systems with a computer at the nav station and another display at the helm.
------------------------------------------------------------------
| Jeff Griglack             "Jabberwocky" P-365 #269
------------------------------------------------------------------
| "Don't take life so serious, son, it ain't nohow permanent"
|                   - Walt Kelly
| 'Years ago my mother used to say to me, she'd say, "In this
| world, Elwood, you must be" – she always called me Elwood –
| "In this world, Elwood, you must be oh so smart or oh so pleasant."
| Well, for years I was smart. I recommend pleasant. You may quote me.'
|               —James Stewart as Elwood P. Dowd
------------------------------------------------------------------


Kobus Meyer

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Apr 23, 2024, 3:17:31 PMApr 23
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Hi Jeff

I run my OpenCPn from a MacBook Air and have no issues. 
In fact I am in the process of building out my Polar Diagrams so I can use it in passage planning. 

I helped a friend build an open system. He got two small Windows computers that run two touch screens with OpenCpn on each at the helmstation and inside his salon. He is very happy with the setup.  A  raspberry PI will be a nice project. 

I also tuned Na ionics on my phone and tablet with some NMEA input there for AIS. 

Kobus Meyer
Pearson 365 - “Wind Sloth”
0.12 kts  Maximum, when threatened

Home Port - Kemah Tx

On Apr 23, 2024, at 08:33, Jeff Griglack <grig...@gmail.com> wrote:


Kobus,

I agree with you on building things up yourself, but a lot of people won't want to go through the work.  BTW, Airmar is a wholly owned subsidiary of Amphenol Corp., not Garmin.  You can buy from them directly and get tech support from them (and they're responsive and support their old products).  The (old) RayMarine speed/depth/temperature sensor is actually made by Airmar and set up to talk SeaTalk (no, not SeaTalk II which is essentially NMEA-2000).  They make these sensors for a lot of the navigation system manufacturers.

What are you running OpenCPN on?  The nice thing about this is that you can run it on an off the shelf laptop, if you want, or a dedicated board (like a Raspberry Pi board running Linux).  I have a couple of older laptops sitting around, so I can have backup systems available.

A couple of years ago, I picked up a Davis anemometer made for a household weather station.  I found a site with code for the Arduino board, but I pushed the whole thing to the background.  Recently, I have revived my project and modified the code a little. I want to feed this into Signal K and OpenCPN.

I have been using Navionics on an 8" tablet at the helm, but you can set up your OpenCPN system with a VPN and display it on a waterproof tablet at the helm.  That's not really much different from what I have seen for B&G or RayMarine systems with a computer at the nav station and another display at the helm.
------------------------------------------------------------------
| Jeff Griglack             "Jabberwocky" P-365 #269
------------------------------------------------------------------
| "Don't take life so serious, son, it ain't nohow permanent"
|                   - Walt Kelly
| 'Years ago my mother used to say to me, she'd say, "In this
| world, Elwood, you must be" – she always called me Elwood –
| "In this world, Elwood, you must be oh so smart or oh so pleasant."
| Well, for years I was smart. I recommend pleasant. You may quote me.'
|               —James Stewart as Elwood P. Dowd
------------------------------------------------------------------


On Tue, Apr 23, 2024 at 10:02 AM Kobus Meyer <svwin...@gmail.com> wrote:
I have a whole suite of Raymarine products but I will never do that again. Also no more full Garmin or B&G system. Will cherry pick things like radar etc but no more expensive chart plotters. OpenCPN and Navioncs (or similar app) will do. 

I will build my open source system with select brand pieces like the Garmin Airmar transducer. Told a friend and heinstalled it and is very happy with it. 

Dave Cole

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Apr 23, 2024, 7:34:47 PMApr 23
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I looked into it a few years ago, but I believe that Airmar makes most of the sensors for consumer depth, speed, fish finders, side scan sonar, etc.

Dave

Jonathan Boright

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Apr 28, 2024, 3:12:38 PMApr 28
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Tanks again all. This is all good info and I certainly see the benefits of getting NMEA200-compatible devices where possible... and I love the idea of adding a wifi gateway so that I can use a tablet or even an iPad as a display device. Open source sounds good to me too (I'm a data scientist IRL and use almost exclusively open-source tools)... and I'll look into OpenCPN.
A question about the combined speed/depth transducers (like the one that Kobus suggests); Are there drawbacks to having them combined? Does anyone have anything particularly good or bad to say about these units? I currently have 2 thru-hulls.. one for the depth sensor (along the centerline of the boat in front of the keel), and one for the speedo (on the starboard side, not too far (16'?) from the depth transducer). Both need to be replaced. Presumably, I'd install the combined unit where the existing depth transducer is. Does this make sense or are there advantages to having two separate units? 

Thanks again for your thoughts...

Jon 


Jonathan Boright
bor...@isciences.com
Research Scientist
ISciences, LLC
126 College Street. Suite 330 (note new address)
Burlington, VT  05401
main: (802) 864-2999direct: (802) 448-7824


Water and Climate, Corporate Sustainability, Remote Sensing, Human Security

Jonathan Boright

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Apr 28, 2024, 4:01:55 PMApr 28
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Also, for context, my vessel is P26, and I'll be using it predominantly for day sailing. I'll mostly need a display device in the cockpit, and not necessarily any computer at the nav station. At a minimum, I'd like a waterproof display to show me depth and speed. Wind as well if I end up getting a new anemometer (might not happen this year). Any suggestions for an appropriate display unit? Perhaps something like this Triton² Digital Display? It seems pricey for what it is... 
If I DO go to the next level and incorporate a chartplotter into the mix (Tablet running OpenCPN or otherwise) would that replace the combined wind/speed/depth display unit? or be in addition to it? I'm realizing now how little I know about these systems(!) I have a Navonics account already... just got it and don't really know how to use it yet, but I can at least see a depth chart and my position on my iPhone.  If I do decide to go the OpnCPN route, I assume that I'd also need to get a separate GPS unit? or is there a way to use the location information from my iPhon/iPad? 
So many questions... so I'll stop there.
J  

Jeff Griglack

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Apr 28, 2024, 9:59:45 PMApr 28
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There is an OpenCPN version that was ported to Android, but I have never used it.  In my mind, a better way to do it is to use a tablet to VNC into a dedicated unit down below, but it doesn't have to be fancy.  People are running OpenCPN on a $60 RaspberryPi with a cheap display (or headless).  The computer running OpenCPN needs a GPS dongle (something like the one linked below) to receive GPS.

------------------------------------------------------------------
| Jeff Griglack             "Jabberwocky" P-365 #269
------------------------------------------------------------------
| "Don't take life so serious, son, it ain't nohow permanent"
|                   - Walt Kelly
| 'Years ago my mother used to say to me, she'd say, "In this
| world, Elwood, you must be" – she always called me Elwood –
| "In this world, Elwood, you must be oh so smart or oh so pleasant."
| Well, for years I was smart. I recommend pleasant. You may quote me.'
|               —James Stewart as Elwood P. Dowd
------------------------------------------------------------------

Jeff Griglack

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Apr 28, 2024, 10:14:23 PMApr 28
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------------------------------------------------------------------
| Jeff Griglack             "Jabberwocky" P-365 #269
------------------------------------------------------------------
| "Don't take life so serious, son, it ain't nohow permanent"
|                   - Walt Kelly
| 'Years ago my mother used to say to me, she'd say, "In this
| world, Elwood, you must be" – she always called me Elwood –
| "In this world, Elwood, you must be oh so smart or oh so pleasant."
| Well, for years I was smart. I recommend pleasant. You may quote me.'
|               —James Stewart as Elwood P. Dowd
------------------------------------------------------------------

Dave Cole

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Apr 29, 2024, 11:22:38 AMApr 29
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Many of the nicer Android tablets have built in gps.  Like the Samsung Active Waterproof units.   I assume Opencpn can use the onboard GPS.  Navionics can use the onboard GPS.
Likewise the onboard Gps allows for SOG to be shown on the screen as well.   I did Vnc setup to a laptop and found it to cumbersome.  

Dave
10M 



Jeff Griglack

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Apr 30, 2024, 3:18:07 PMApr 30
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The advantage of a small, dedicated computer at the Nav station with OpenCPN and SignalK is that you can feed the other peripherals into it from your NMEA 0183 or 2000 network.  I don't know if you can do that with the Android version of OpenCPN.

The reviews on the Android version of OpenCPN are a little mixed for me.  It looks like there are some things that work on the Windows/Mac/Linux versions that do not work on the Android, but, frankly, I've never tried to use the weather routing anyway.  I suppose it would probably be worth the $10 to try it out, and then you can use the tablet's internal GPS.

This season, I think I will spring for the Android OpenCPN and another year of Navionics and see how they compare in real time.
------------------------------------------------------------------
| Jeff Griglack             "Jabberwocky" P-365 #269
------------------------------------------------------------------
| "Don't take life so serious, son, it ain't nohow permanent"
|                   - Walt Kelly
| 'Years ago my mother used to say to me, she'd say, "In this
| world, Elwood, you must be" – she always called me Elwood –
| "In this world, Elwood, you must be oh so smart or oh so pleasant."
| Well, for years I was smart. I recommend pleasant. You may quote me.'
|               —James Stewart as Elwood P. Dowd
------------------------------------------------------------------

Dave Cole

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May 2, 2024, 1:31:09 PMMay 2
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Not that it matters to our installations, since we have to deal with what is available, but in general the NMEA 2000 standard has been a failure.    
It has not been widely adopted as "the" standard.   Many companies have come up with their
own network which may only be partially compatible at best.  

A couple of years ago I was looking at the NMEA standard and there was a push to go to a newer standard which is based on Ethernet.    
I just looked again and I found this:


If you can, I would try and go in this direction.   Power over Ethernet is very common.  You can buy POE switches on Amazon, etc.  It is widely used for security cameras.
Plus Ethernet has a huge bandwidth.  Running video/radar images across it is no big deal.

I have a POE switch on my boat that connects to a camera on the dock, screwed to a dock post.   I use a Raspberry Pi to gather the video and serve it up to the web via the marina wifi so I can check the dock lines remotely.  
I'm about 2 hours from my boat so it has saved a lot of worry.  

Dave
10M #26

Peter McGowan

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May 2, 2024, 2:17:40 PMMay 2
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Personally I’ve avoided mixing brands because there’s a reasonable chance
a company like B&G or Garmin will test that their products work well together over NMEA2000 than that they will work well with competitors products.  I would be surprised if NMEA OneNet changes this dynamic.

For companies where interoperability with other brands is crucial, like with Airmar or Victron, I expect significant testing occurs on their end, and I believe this is why I’ve had no issues with Garmin, Airmar, Actisense, and Victron on my NMEA2000 network.  

I like that NMEA OneNet will support radar (and I expect sonar?) so that’s huge.  but hope to never have more than 60 devices on my network.  It’s never bothered me that some devices, like my chartplotter and radar, need dedicated power, I fact I like that when I leave the boat I can kill power to them from my switch panel.  Now, of course, a NMEA OneNet device that allows me to remotely turn stuff off devices, that would be sweet.  But I’d have to watch my passwords carefully…

Jonathan Boright

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May 5, 2024, 1:31:16 PMMay 5
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OK, lots of info to digest in this thread... thanks for that. 
Where I'm finding myself settling is that, for starters, I'm looking for reliable thru-hull transducers that will last a while and play well with other devices on a simple onboard network. Even with its failings, it seems like NEMA  2000 is the generally accepted standard... at least most products are built for it or have adapters to make them work with it... so my goal is to choose some reliable depth and speed sensors and hook them to a NEMA 200 backbone, to which I'll eventually (once I'm in the water) add other fancy things (like a raspberry-pi and connected chart plotting capability). Finding those basic transducers with good reviews, though, is proving a challenge. The Garmin Airmar DST810 Smart Transducer seems like a logical choice (NEMA 2k output)... but the reviews are pretty ambivalent. The other ones that keep popping up are the Garmin GDT 43 and GST 43 Transducers, not NEMA2k, but can be brought to a NEMA2k network with a Garmin NMEA 2000 adapter. I haven't been able to find any review of the transducers themselves though. Does anybody out there know of other current, reliable transducers for a NEMA 2000 network? 

Also, the other issue that I'm facing is the placement of the existing transducer thu-hulls on my P26. They are beneath the black water tank... which makes them very awkward to access. I'm contemplating moving them (or a singular one if I'm going with a combined depth/speed sensor) forward a bit (~8") so that they can lie in the space between the black and freshwater tanks. Do any P26 owners out there have this issue and how have you managed it? 

Cheers!

Jon   
   

Jonathan Boright
bor...@isciences.com
Research Scientist
ISciences, LLC
126 College Street. Suite 330 (note new address)
Burlington, VT  05401
main: (802) 864-2999direct: (802) 448-7824


Water and Climate, Corporate Sustainability, Remote Sensing, Human Security

Dave Cole

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May 5, 2024, 2:23:19 PMMay 5
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Have you tried going right to the Airmar website?
Also do a search on youtube for Airmar and you will see a lot of videos on Airmar sensors.
If I was to do it from scratch id probably try and get the data to an ethernet hub and go from there.  If you have to get there via nmea 2000, oh well.  I have little faith in the marine electronic  suppliers.  Raymarine and Garmin have both stung me.  Buy it and two years later its unsupported.  Years ago I bought a fish finder which at the time cost more than my outboard motor.  Just after the warranty  expired, it malfunctioned and Raymarine refused to repair it period.  I gently placed it in a trash can, said a few words,  and walked away from Raymarine for good.
Raymarine has been bought, sold, and reorganized a number of times.  

Dave
10M #26

Jonathan Boright

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May 5, 2024, 4:23:29 PMMay 5
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Thanks Dave, 
Going directly to the Airmar website and YouTube was the answer... I'm pretty sold on the Airmar DST810 at this point. And really, it looks like the Airmar CAST app alone provides 90% of what I need(want). It would be nice to add wind data at some point... but that can wait 'til I'm in the water. I'll not be adding sonar or radar anytime soon (or ever to this boat), and I won't have wifi, or even shore power for that matter, either on this boat so I think going right for NEMA OneNet is overkill. I think that the DST810, a raspberry pi, OpenCPN, and a waterproof tablet are part of my target solution. I'll start with the DST810 though.  

J
-------------------------------------------
Jonathan Boright




Dave Cole

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May 5, 2024, 5:19:59 PMMay 5
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If you end up doing that let us know how it goes.

Dave
10M #26

Jeff Griglack

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May 5, 2024, 9:45:24 PMMay 5
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For my part, I finally figured out how to change the setting on the old AutoHelm ST50 depth in my boat.  I know I mentioned this a while ago, but the depth was about 3 feet off when measured with a weighted line.  It turns out that the offset was set to +4.6 feet and it should have been set to  about -3 feet to measure the depth under the keel.  The boat draws 4.5 feet, but the sensor is probably about 1.5 feet down.

The ST50 is a pretty old display, and they can be a little hard to read in direct sunlight, but I would like to keep them going for another year or two.  The sensor unit is an Airmar 2-399-01 which was set up to talk SeaTalk and appears to be working even after all these years.  I'll just be happy if I don't run aground while it's telling me I still have 7 feet of water.

When I replace it, I am thinking about the Airmar UDST800 which uses ultrasonics to measure the speed, so no paddle wheel to clean.  However, it will not fit in the existing thru hull for my old unit.  Also, I am not sure if the ultrasonic transducers work with Bluetooth.

My boat has been in the water for a week and (that's the sound of me knocking on wood) everything is working fine.

Jeff
------------------------------------------------------------------
| Jeff Griglack             "Jabberwocky" P-365 #269
------------------------------------------------------------------
| "Don't take life so serious, son, it ain't nohow permanent"
|                   - Walt Kelly
| 'Years ago my mother used to say to me, she'd say, "In this
| world, Elwood, you must be" – she always called me Elwood –
| "In this world, Elwood, you must be oh so smart or oh so pleasant."
| Well, for years I was smart. I recommend pleasant. You may quote me.'
|               —James Stewart as Elwood P. Dowd
------------------------------------------------------------------

Peter McGowan

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May 5, 2024, 9:55:08 PMMay 5
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That paddle wheel cleaning is a PIA, it’s like every weekend here in southern Maine / NH Seacoast.   I have a UDST800 right next to me in box ready to install before splash this season (I believe it will fit in the DST housing, otherwise I’m in for some disappointment). Looking forward to skipping the weekly flooding of the bilge…

Jeff Griglack

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May 5, 2024, 10:03:35 PMMay 5
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My understanding is that the UDST800 will fit in any modern Airmar thru hull.  Mine is just way too old.  Can you follow up with a message telling us how it works for you?

Jeff
------------------------------------------------------------------
| Jeff Griglack             "Jabberwocky" P-365 #269
------------------------------------------------------------------
| "Don't take life so serious, son, it ain't nohow permanent"
|                   - Walt Kelly
| 'Years ago my mother used to say to me, she'd say, "In this
| world, Elwood, you must be" – she always called me Elwood –
| "In this world, Elwood, you must be oh so smart or oh so pleasant."
| Well, for years I was smart. I recommend pleasant. You may quote me.'
|               —James Stewart as Elwood P. Dowd
------------------------------------------------------------------

Peter McGowan

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May 6, 2024, 7:23:36 AMMay 6
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Guy Johnson

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May 6, 2024, 8:06:02 AMMay 6
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I have B&G displays with Airmar DST800 sensor, I'm happy with all of the pieces. 
NEMA 2000 isn't the most sophisticated network, but it's works well for my needs. 

Guy
Puffin
10M #6

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Sent: Monday, May 6, 2024 7:23 AM
To: pearso...@googlegroups.com <pearso...@googlegroups.com>
Subject: Re: [pearson ] Nav electronics replacement
 

Jonathan Boright

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Jun 5, 2024, 11:01:51 AMJun 5
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Looping back to this thread... I ended up going with the Airmer DST810. The next question is where to put it. 
So a question for the group; Do you generally remove your transducers that have protrusions (paddle-wheel style speed transducers for example) at haul-out and put-in? I ask because the current locations of both my speed and depth transducers (neither one is functional and the DST8100 will functionally replace both) are not easily accessible and would be very difficult to remove on a regular (or emergency) basis.

In my P26 the current depth transducer (non-removable model) is just in front of the keel and directly below the black water tank (not accessible) under the v-berth. The speed transducer is about 8 inches away,  to starboard and slightly forward, and is almost (but not quite) free of the tank above it. Here are two pictures: one with the blackwater tank in, the other with it removed. 


image.png

Last fall when we were winterizing the boat, we noticed that the speed transducer housing was broken, and appeared to be forced up from below with enough force to break the pvc housing at the connector pin (see below).
Speedo thru-hull 2024-02-03 104050.png
The transducer unit was only prevented from coming out entirely because it hit the black water tank above it (see the first picture). This would certainly have sunk the boat if the black water tank hadn’t stopped the unit (!). I suspect that this happened at haul-out when a strap was placed over the paddle wheel... but I don't really know that. All this makes me reluctant to put any through-hull in an inaccessible spot… especially one with any protrusions.

It seems like the Ideal spot for the new (Airmar DST810) transducer would be on the centerline in the (easily accessible) space between the fresh and black water tanks… about 8” forward of the existing through-hull. This would entail cutting another hole in the hull... and patching up the two that aren't used anymore. The easier route would be to use the existing hole from where the currently broken speed transducer is… but, as I mentioned, it doesn’t clear the black water tank, and if I can’t swap it out before haul out (or in an emergency) this whole scenario might happen again.

Does anyone have some perspective? Worth it to drill a new hole in the boat to make it happen? Better to use the existing hole and get sailing already?


Thanks

-------------------------------------------
Jonathan Boright




Peter McGowan

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Jun 5, 2024, 12:12:36 PMJun 5
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I had to regularly pull my paddlewheel transducer during the season to clean it and I’m glad it was easy to access.  I’m hoping not to have to do that with the new one, but if I find that a layer of slime is affecting it then it’s easy to access for a quick wipe.  

I don’t like thru hulls in places I can’t easily access, your plan to patch them sounds like a good one to me.

Jonathan Boright

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Jun 5, 2024, 1:45:09 PMJun 5
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Thank's Peter. I think that the only reason to NOT place the transducer in the desired (ideal) spot (and it might actually win the day) is timing. I'd like to sail this summer, and this project isn't the only one left before splashing... the other ones are bigger (transom and cockpit sole core replacement). The easier (quicker) option would be to put the transducer in the old speed transducer hole for this season, and perhaps moving it to the better location next year. From a safety perspective, I'm not too concerned about the paddle wheel getting gunked up (I can swim underneath and clean it occasionally)... but the risk of a marina lift strap punching it through the hull again has me concerned. Is this a reasonable fear? Is there any expectation that the boatyard can avoid the projecting through-hulls if it tries?



Jonathan Boright
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ISciences, LLC
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Dave Cole

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Jun 5, 2024, 2:52:14 PMJun 5
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I would try to avoid locations where the lift straps go.
However its not likely that the strap pushed the transducer up enough to break off the connector.

Have you considered slightly moving the blackwater tank?  That is likely a lot easier than patching an existing hole and making a new one.  Is it possible it has shifted over time?  

I would do something temporary and get the boat in the water.  If you are new to boats, you will soon realize they are one big ongoing project.  Much like a house;  There is always something that needs to be done.

Dave
10M #26