Depth Sounder

[Nero]

I have a new 26M used now for one season. Unfortunately we didn't pay enough attention one day and smashed our first daggerboard. I'm thinking about installing a depth sounder in order to reduce the risk in the future. My questions are: any experience with installing depth sounder on the 26M ? Any model you recommend ? My biggest concern is the installation. As I think the sounder needs to sit in the bottom of the boat. There is the water ballast tank. Any spot which might work out safe without getting as leaking boat and have a huge huzzle getting this installed? Appreciate very much your comments and advice ! NERO

[Scott]

Buy one with a programmable low depth alarm and mount it forward and pointed forward. No good knowing the water is 3 feet deep after you run a ground. one problem we had with our depth finder was reading it heeled over. 6 feet of water would read as 18 feet. It really was 18feet at a 45 degree angle.

There s a lot to be said for owning a good topo map of your sailing grounds and knowing it well.

[Hardcrab]

You will get many different answers from those who have gone before you.

An "in the water" location gives the best echo returns, according to my manufactures instructions.
But, I did not want screw holes in the hull.

So, I mounted mine "in the water" but attached to the ballast dump valve.
Not a standard location, but I wanted the temp along with the best depth/fish returns.
Holes are only in the dump valves short pipe.
A big stainless steel hose clamp around the valve, small stainless steel screws, some minor fabrication of an interface, and the fun of the challenge.
Wire routing is up the motor mount, then along with the motor wiring to the console.

A nice, clean installation and it has worked out perfectly for the last two years.

[tangentair]

So, I mounted mine "in the water" ....

Me too, but I used a piece of very dense "plastic" and used spots on the engine bracket to attach it so that it sits between the engine and the rudder. Works pretty good there, I set the depth alarm at 6 feet and it only goes off when I am close to the ramp and under power - but I sail in Lake Michigan, - I agree with Rich that it only tells me how deep (and what fish) I just past over not what is coming.

[Terry]

If I read the booklet on depth sounders correctly I get the impression that they scan the water depth in a 'V' forward direction with the point of the V eminating from the transducer, thus the deeper the water the more forward reading it is and conversely the shallower the water the less forward reading it is. At 20' one should realize that it is time to be more careful. I have my daggerboard line marked at 30" so that the DB can be set to the same depth as the rudders when it gets shallow.

[Russ]

My transducer came pre-installed from the dealer on the transom. On other boats I had it mounted inside the hull in a "bowl" of silicone caulk. But I guess that won't work on a Mac with it's "two" hulls.

It depends on where you boat, but I've found that by the time the depth sounder warned me, it was too late. Still, I like knowing how much water is under me, if for nothing else, anchoring.

There is no substitute for good charts and seamanship.

[Kevin]

I mounted my Lowrance fish finder/depth sounder against the hull under the port settee. The sounder was designed to be transom mounted but I don't like the idea of it hanging off the back and subject to being bumped. I mounted the sounder by pushing it into a glob of plumbers putty pressed against the hull. I experimented with positions until I got good readings and rocked it a bit until the fish indications were nice ^ shapes. This worked great for the 3 years I owned the Dwen.

I have an opinion (like everyone else) on positioning the sounder. I like it close to the center of the boat on both axis. My reasoning is:

1) the boat planes under power. Mounted too far forward and it will be out of the water in some conditions.
2) when heeled keeping it close to the center also keeps it in the water.
3) At 20 mph I don't think it makes much difference whether the sounder is in the front or hanging off the transom. You'll see the water getting shallower and 20 feet difference in warning doesn't make a difference.

I guess one possible scenario where the position of the sounder could make a difference is if you were anchoring next to a shelf. Maybe if you were trying to feel your way around rocks at dead slow speed?

[puggsy]

With new buyers coming online from time to time, it seems there is a need to sometimes repeat advice. As to depth sounders on a with the 'peculiarity' of its ballast system, to my mind the best fitting is via a " wetbox". some owners have suggested similar by setting the transducers in putty.the whole point being to eliminate any air space between the transducer and the outside water environment.
I mounted my 'humminbird Matrix 12' transducer in a sealed container fixed with silicone sealer direct to the hull at a point where there is only the one layer of fibreglass...a bit to port of the ballast section. The 'container is a bit of 12 inch X 6 inch waste water PVC pipe with a cap to seal the top . Fit the transducer on the inside wall facing forward and fill with cheap vegetable oil . The signal goes through the oil, then the hull, then the water environment, and a good echo is received off the bottom. The secret is in eliminating air pockets. It is the air bag in a fishes gut that the sounder/ fish finder reads...and shows...Puggsy

[delevi]

I believe a chart plotter is more useful than a depth sounder. As has already been said, by the time the sounder tells you you're in shallow water, it is often too late. A plotter, on the other hand, shows you the depth of the water ahead of you. Not saying you don't need a sounder, but a gps/chartplotter is a fabulous instrument to have on your vessel. I have both. My transducer is mounted on the transom abit starboard of the engine.

Leon

[James V]

Mine is like Keven's. I have it set at 6 feet and my dagger board is at 3 feet. It would be nice to see far enough ahead to not run aground but I am affraid it would not make much of a change moving the sensor infront of the dagger board due to the speed of the boat and the ability to react in time.

All reviews of the Depth sounder is about the same. Some units are smaller. If you have not bought a GPS Map then take a look at the ones that come with a depth sounder. I have a seperate one as I wanted it seperate from other devices incase of a failure.

[puggsy]

Hey! Delevi...If it can be afforded, its best to have BOTH...The depth sounder AND a chart plotter/ GPS.
I dont know abouth the U.S. scene, but over her we have large parts off the coast that were last depth tested in the late 1800's. Before engines even...
Its best to use both units together...Last week I took SEAHORSE into an area THAT HAD NO DEPTH AT ALL marked on the chart. Turned out it was about knee deep for hundred of meters/ yards...and we were able to carefully motor over it...the sounder was showing less than two feet...and my LOWRANCE handheld GPS told my my Lat. and long. and showed where we were on the built in chart. As I said, its best to have both. Puggsy

[Paul S]

I mounted my transducer in a pvc pipe section 5200'ed to the hull (not on the ballast tank) under the stern berth. I fill it with water, and it is good to go. Works flawlessly. Can't knock it off or otherwise damage it. no holes being drilled into the boat!

Running the garmin 440s. Great plotter - fast - clear - easy - (realativly) inexpensive

I found no reason to mount it further forward.. IF it alarmed while going 5 knots, there is no way to raise the DB and rudders in a fraction of a second!

Sounder + chart (and GPS plotter as backup) = no broken DB (yet anyway)

The sounder, like a GPS plotter are BACKUP to good navigation skills and experience. Unless you play Captain Ron and burn the chart..they will never go blank like a GPS can (happened to me 3 times in 5 years).

[Don T]

Hello,
+1 for putting the transducer "shoot through" under the aft berth. Too far forward and performance is spotty when throttling up due to air in the water. In the rear mounting you will get good readings while planing. It also has a forward look under those conditions cuz' we motor nose high. My tranducer came with it's own adjustable collar to compensate for the "V" of the hull and desired angle forward. That is RTV'd into position, add mineral oil or biodegradable antifreeze, then the transducer is mounted (it has O-ring seals). Nice easy clean install.

Don

[PollyAnna]

All,

I had my sonar from my Garmin 545S mounted on pole that was tie-strapped to the side of the swim ladder. Worked great for the first few months, but alas, it got knocked off passing over some stumps. So I am real interested in mounting it in a "wet box" in the aft section of the boat.

Does anyone have and pictures they can share? I think I get the concept, but it would be nice to have visuals to support my understanding.

Thanks in advance,

Gregg

[Québec 1]

A depth sounder will not stop dagger board breakage. Extreme caution probably will. A paper chart is as good and in many cases better than a depth sounder.
Q1