Sailing without depth sounder?

[Bill O]

Agree with Fred that it is an unnecessary risk to sail a boat w/a 7'10" draft w/o a d/f.
Again not knowing the exact build of a Tripp 41 hull grid system, if it is anything like a Beneteau grid and do a hard grounding, you could total the boat.

Even w/our 6.5' draft, a d/f is an essential piece of equipment. We only have 2, a regular d/f mid boat and a forward scan.

[George_SD]

Originally Posted by Notyetsinking

Good idea. The boat is cored, though I don't know if that is just above the waterline or the entire boat. So maybe that would work? For $120, might be worth a shot! Certainly goes to show there is quite a heavy sailing tax....a 20 year old B&G transducer is more expensive than that!

Even if it is cored and it doesn't work well - you can always rig it to a pole attached to the railing whenever you get into shallow OR mount it to your stern since it comes with a stern mount bracket.

[wingssail]

Originally Posted by George_SD

Even if it is cored and it doesn't work well - you can always rig it to a pole attached to the railing whenever you get into shallow OR mount it to your stern since it comes with a stern mount bracket.

If you have good access to a flat part of the bottom, like just ahead of the keel, and the hull is cored at that point, you can cut away the inner skin with a large hole saw, remove the core material, then carefully make a solid lamination at that point, and you should be able to shoot depth sounder signals through the new lamination with little attenuation. All you do is place the transducer, any transducer, on the single thickness part of the hull. You can glue it with silicone, you can epoxy it, you can even just sit it there in a puddle of water just avoid air bubbles.

Three of my four transducers are shooting through my solid glass hull (the fourth is part of the speedometer transducer and so it is immersed externally to the hull).

[Chotu]

Originally Posted by wingssail

If you have good access to a flat part of the bottom, like just ahead of the keel, and the hull is cored at that point, you can cut away the inner skin with a large hole saw, remove the core material, then carefully make a solid lamination at that point, and you should be able to shoot depth sounder signals through the new lamination with little attenuation. All you do is place the transducer, any transducer, on the single thickness part of the hull. You can glue it with silicone, you can epoxy it, you can even just sit it there in a puddle of water just avoid air bubbles.

Three of my four transducers are shooting through my solid glass hull (the fourth is part of the speedometer transducer and so it is immersed externally to the hull).

That’s what they say. Didn’t work for me. I probably got an air bubble in the epoxy.

Question. I have one of those Raymarine forward looking sonar Sounders.

It looks like this. It’s meant to be mounted on the back of a power boat.

Any ideas on mounting this thing on a catamaran?

Came for free with my axiom 9. Believe it or not. A $500 item. West marine promo.

[Fore and Aft]

Chotu a Prout Snowgoose I surveyed last week had a similar depth sounder mounted on an aluminium pole. If you could pivot it up out of the way when in deep water it would be a good idea.
Cheers

[Chotu]

Originally Posted by Fore and Aft

Chotu a Prout Snowgoose I surveyed last week had a similar depth sounder mounted on an aluminium pole. If you could pivot it up out of the way when in deep water it would be a good idea.
Cheers

I was thinking of something like that. A pole that you can drop down when you need it. But I thought that might be a little weird and I might have been missing a better way. That might be the only way however. Thanks for confirming someone else has done this

[George_SD]

Chotu - i may not have worked for you if it was not low enough frequency. The sideview/3D sonars (like the RV in your picture) are typically much higher frequency ranges that don't do well going through the hull. However traditional ones with ranges about 50-250 should have no problem

[Chotu]

Originally Posted by George_SD

Chotu - i may not have worked for you if it was not low enough frequency. The sideview/3D sonars (like the RV in your picture) are typically much higher frequency ranges that don't do well going through the hull. However traditional ones with ranges about 50-250 should have no problem

No, it’s the traditional one that I have going through the hull.

The one in the picture I got for free with my new axiom 9. It’s just sitting in a box right now

[JPA Cate]

Draft is 7`10, with about 4ft ish of freeboard , which is why we are looking into handheld depth sounder. The forward scans are something we are very interested in; they seem to be invaluable tools for exploring new areas. How do you like yours?

Both the last two boats draw 2.2 m (about 7'2"). We liked the Probe. So much we bought a new one for the most recent boat, before we gave the PO the money! However, they are no longer available, and sorry, but I'm not up to date with the market now. It was sort of like radar, in that you have to learn to understand what the display meant. It was an up and down, not a side to side, but very useful in poorly or non-charted waters, especially murky waters that hide sharks and 'gators or crocs.

Ann

[wingssail]

Originally Posted by Chotu

That’s what they say. Didn’t work for me. I probably got an air bubble in the epoxy.

Question. I have one of those Raymarine forward looking sonar Sounders.

It looks like this. It’s meant to be mounted on the back of a power boat.

Any ideas on mounting this thing on a catamaran?

Came for free with my axiom 9. Believe it or not. A $500 item. West marine promo.

I'm not sure why your "shoot through the hull" installation didn't work. There are some diagnostic tests that could be done.

As for the one you pictured, if it was me, I'd choose a hull, either one or the other, and mount it on the back of that hull. Not optimal, but what else could you do? On my monohull I'd have no idea how to do it.

It might not work when you are going fast and lifting a hull, but gonig slow it should work.

[GordMay]

Originally Posted by wingssail

I am a firm believer in depth sounders. ...
... Many people navigate with far less depth sounding capability. In my view, they are taking an unnecessary chance. They can get away with it for many years, but that does not mean it is safe, it means they have been lucky ...

Over a total of about 10 years, I sailed 2 different boats, without depth sounder[s]. Poverty, not judgement, dictated that/those choice[s].
I was [sort of] lucky, in that, neither boat ever came to harm; but I painted a lot of rocks [bottom paint blue/black], in Lake Superior; and gouged out numerous channels in Bahamian sand banks, over the years.
I’ve never been recognized, for these public services.
I too, ‘am a firm believer in depth sounders.’

[OS2Dude]

While true that people have been sailing for centuries without a depth sounder, don't forget that people have been going aground for centuries too. Casting a lead is fine if you have a measured line and someone to stand in the bow who can do the sounding fast enough so you don't travel faster than the readings can be made. You don't want your keel to ground if the bottom suddenly rises up.

If you are fairly familiar with the area, you should be fine. I would not go exploring unknow areas, however.

If you don't need the visual 'fish-finder' part, a straight NMEA depth sounder would be a good choice as well. Non-proprietary. Some include temp & speed as well if you get a thru-hull transducer. In-hull transducers can not measure speed or water temp.

[jcgriz]

We just returned from a trip to Desolation Sound and Vancouver Island. On our way north, BOTH of our depth sounders went out within a day of each other. I thought it might be a deal-breaker for the trip, given we couldn't get a repair or replacement on the way. This is what we did:

1. Downloaded Navionics maps for the area on my phone, which is very well charted.
2. When anchoring, switched to "fish finder" Sonar maps (also an option on our Garmin chartplotter). This gives a much more detailed view of the bottom.
3. Generally anchoring in deeper water -- never putting ourselves on the edge of knowing we could be in 1-2 feet of water at low tide, which we often do with a working depth sounder. We got more comfortable anchoring deeper and putting out more chain.
4. Putting a pin on the Navionics chart before deploying the anchor so we knew our anchor depth, after accounting for the tide.
5. Using a lead line to double check our depth vis-a-vis the charts after anchoring. We were always very close which was reassuring.

I was skeptical, but it all worked out great. In fact, I realize we probably err too much on shallow anchoring when we do have a DS.

Oh, I also learned that the Canada and the US compute tidal datum differently. Canada uses the Very Low Low Tide as the base, and the US uses Medium Low Tide as the base. So the tide generally looks higher in Canada and there are fewer minus tides. Good to know where the data is coming from if you're relying on it to that extent.

[singlespeed]

I ran into the same sort of issue when lightning took out our electronics in the ICW. Long waits for individual components and fused wire bundles to be removed to rewire the replacements. Just buy a cheap or used transom mount fish finder. Most are 12VDC. You can usually find a source for a extension for the cabling from the sender to the display. Mount the sender on a pole and send someone to the bow to hold the sender in the water. Obviously you are going to be moving slowly, so keeping the sender in the moving water is not difficult. Worked extremely well, especially when barge traffic forced us to hug the starboard side of the ditch. We finally used hose clamps to temporarily attach it to the bow pulpit and ended up keeping this for most of the return from DC to Riviera Beach. Ugly, but it never failedus . Finally got all the new components and sold it to a fisherman for a little more than we paid for it.

[Turtle Blues]

Boat US membership with the proper level towing? Over 30 years it has been used enough to be worth every dollar it cost.

Takes a couple of days to activate so you can't call after the fact.