Association Forum - Fish Finder?

Assn Members Area · Join

Home.

Association Forum

Ships Store

Cruising

Racing

Technical Tips

Photo Gallery - New

Boat Search - Updated

Manuals & Brochures

Swap Meet

Links

Officer Flag Line & Staff

Bylaws & Constitution

Members Area

Join the Association

Notice:
The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.

Association Forum

Username:	Password:
Save Password
Forgot your Password?

All Forums

Catalina/Capri 25/250 Sailor's Forums

Catalina 250 Specific Forum

Fish Finder?

New Topic

Topic Locked

Printer Friendly

Author

Topic

doublereefed
Navigator

Member Avatar

167 Posts

Initially Posted - 07/23/2017 : 14:50:06

I am researching adding a fish finder. I like the Humminbird line. I am wondering if the new(er) transducers (top sonar, side sonar, who knows what else) still register while heeled and sailing. I imagine the side to side readings may be affected while heeled on side scan, I wonder if the bottom/depth reading is affected by the transducer being heeled? Not only would I like to find the fish... but I also think it would be fun to be watching the bottom go by...

Thanks,

-Richard

'95 C250 WB #61
Midway, UT

Voyager
Master Marine Consultant

Members Avatar

USA
5231 Posts

Response Posted - 07/23/2017 : 19:44:49

Do you plan to mount the transducer inside the bottom of the hull or on the transom? If the latter you may be able to rig a mount that will swing to allow the transducer to remain plumb hole the boat heels. I'm thinking the transducer can be attached to a short piece of pipe that's connected to the transom by a pivot pin at the top of the pipe.
Not totally ideal but would probably be serviceable.

Bruce Ross
Passage ~ SR-FK ~ C25 #5032

Port Captain � Milford, CT

doublereefed
Navigator

Members Avatar

167 Posts

Response Posted - 07/25/2017 : 15:52:33

I'd like to use a through-hull rather than transom mount. Will have to do some further research...

'95 C250 WB #61
Midway, UT

TakeFive
Master Marine Consultant

Members Avatar

2269 Posts

Response Posted - 07/25/2017 : 16:46:50

Do some research. There are ways to mount transducer inside the hull without putting a hole in your hull.

I'd recommend a device designed for sailboats rather than a fishfinder. They're designed to work when heeling. Others might work, but you'd be learning the hard way. Let the manufacturers do the R&D.

Rick S., Swarthmore, PA
PO of Take Five, 1998 Catalina 250WK #348 (relocated to Baltimore's Inner Harbor)
New owner of 2001 Catalina 34MkII #1535 Breakin' Away (at Rock Hall Landing Marina)

OLarryR
Master Marine Consultant

Members Avatar

USA
3367 Posts

Response Posted - 07/26/2017 : 04:06:32

There have been many discussions buried in the archives regarding repairing the old depthfinders, replacing with an up to date depthfinder and/or a fishfinder. I do not recall discussions that were negative on using a fishfinder on a sailboat. If anything, some have gone to fishfinder/chartplotter combo. Also, the discussions regarding determining depth ahead of the boat or when heeling are limited. Most discussions, a fishfinder was installed and discussions centered around the brand/model and installation technique. Granted, if and when the boat heeled at a significant angle, the depth readings will differ compared to being completely in the vertical using a standard transducer - But is the difference reading so critical where you sail ? I sail on the upper Potomac River and if not in the channel, we sure do have depths flirting with 2 feet or so. Still...I have never found using the standard transducer with my Humminbird fishfinder much of an issue when heeled over and then upon righting, flirting with running aground. The fact is you have other considerations that are of an equal or greater concern than the difference in depth when heeling and that is the ripple/wave action that will cause similar differences in depth. Basically, if I get down to anything less than 4', my fishfinder will indicate 3' since it indicates whole numbers but I can tell from the plot if it is closer to 3' or closer to say 3' 10". The other thing is that I did not calibrate my fishfinder for the fact that the transducer is in the hull is actually below the waterline by something like 1/2 foot - so, that 1/2 foot is my safety factor when I flirt with the fishfinder occasionally going from a 3' reading to 2' reading. I generally will tack when I get down to 4' (meaning I really have about 4 1/2' under the hull. If it goes from 4' to 3' reading, I do not stay there long before changing my tack - I'll watch the contour line on my fishfinder to see if it is going to dip lower.

At the time I bought my Humminbird fishfinder, it came with a transducer that could be mounted off the transom or in-hull. The difference based on the instructions were that if mounted in-hull it would still read accurately but strength of signal meant that instead of a range of 1000' off the transom, an in-hull mounting would reduce effective strength to read only as low as 400'. I do not think anyone of us really cares if it can read 1000', 400' or even 200'. I am only interested in depths much less than 50' and the in-hull install is totally accurate in less than 10' of water.

I have now had my Humminbird fishfinder for over 10 years utilizing the original tranducer and never had to re-install the in-hull transducer. Over 10 years ago, I slapped down a blob of a toilet wax ring matl bought in Home Depot and pushed/smooshed the transducer into it. It has worked perfectly all these years.

Below is photo of transducer install and also the fishfinder on a RAM Swing mount. The RAM Swing mount is on a piece of Starboard and the stud bolts that hold it are actually located within the hole diameter of the original depthfinder - So, no holes were drilled in the bulkhead - the bolts being within the original hole diameter means the bolts basically hold the mount via a friction fit, bolts cannot move out of the circle and the Starboard is also fit adjacent to the bulkhead edge. Note also that the transducer is installed nearby the original thru-hull depthfinder transducer. Addl photos on my website.

Larry
'89 Robin's Nest#5820, Potomac River/Quantico, Va
http://catalina25.homestead.com/olarryr.html

Edited by - OLarryR on 07/26/2017 04:17:44

TakeFive
Master Marine Consultant

Members Avatar

2269 Posts

Response Posted - 07/26/2017 : 11:13:13

Looks like Larry tested this out for you. Sounds like a good option. Fishfinders are so popular that the price is probably pretty attractive due to competition.

Rick S., Swarthmore, PA
PO of Take Five, 1998 Catalina 250WK #348 (relocated to Baltimore's Inner Harbor)
New owner of 2001 Catalina 34MkII #1535 Breakin' Away (at Rock Hall Landing Marina)

OLarryR
Master Marine Consultant

Members Avatar

USA
3367 Posts

Response Posted - 07/26/2017 : 11:55:55

I have not done a search/review of transducers/depthmeters for 10+ yrs since it was at that time over 10 years ago that I made my decisions. Perhaps, currently, there are some depth transducers/meters out there that are now specific for sailboats. It is really the case of how psyched up you get into accuracy, etc regarding whatever tools/toys we get for our boats. My own experience was that it would have cost more to replace/repair the old depthfinder with same/equal compared to replacing the depthfinder with a fishfinder and with the fishfinder, I also get a sense of the contour of the river. I say "sense" because it does not provide the actual contour since the screen scroll is time dependent versus actual movement in the water.

You have to give thought as to how sophisticated a system you need (or want...sometimes "want" wins out and that is okay !). Still, you need to exercise caution when flirting with sea bottom and the draft of your boat - Sometimes, there are interferences on the sea bottom - A rock, a steep rise, a tree log, hopefully not a shopping cart! (I once saw 2 of them at low tide just on South end of Natl Reagan Airport Runway/water's edge but believe they were eventually removed). So, one would not want to get down to a depth that approximates the boat's draft. Even so, if you sail frequently, we all eventually get surprised.

Larry
'89 Robin's Nest#5820, Potomac River/Quantico, Va
http://catalina25.homestead.com/olarryr.html

doublereefed
Navigator

Members Avatar

167 Posts

Response Posted - 07/29/2017 : 10:34:29

Thanks for all the great input. My master plan (evil laughter inserted here) is to get a regular sailing instrumentation for depth, speed, and then masthead wind info. That's a few projects (and boat bucks) down the line. So, fishfinder first. I'm sailing in very charted, very predictable waters (reservoirs) so I think a fish finder will work just fine for depth, presuming it still works while heeling. "Works" in this case and for my needs would mean that it gives a reading. If it is off by a few few feet due to the trigonometry of the angle of heel I am fine with that. Here's what Humminbird had to say, even though they didn't directly answer my question:

Reply 1:
"Thank you for contacting Humminbird Customer Service. Most of our units come with "depth offset" to account for the keel. The Helix 9's and the Helix 7's both do. Depending on which model you choose you could exchange the transducer for a "shoot thru hull", provided your boat is single layer fiberglass. We also have a "thru hull" transducer that would require putting a hole in the bottom of boat to install.

Good Fishing and Boating!"

Reply 2:
"If there is contact with water, you will get a reading, if not your depth will be incorrect."

So, I will use a"shoot thru hull" transducer. If it is on the centerline I will be getting readings just fine I think.

A question though... the only access I have to the hull is in the bilge aft of the ballast tank, correct? There's no hull access forward of that on WB?

Best,

-Richard

'95 C250 WB #61
Midway, UT

Russ.Johnson
Commodore

Members Avatar

USA
833 Posts

Response Posted - 07/30/2017 : 09:00:48

Richard,

I'm not sure about the early years, but the later years have a cutout under the v-berth.
It's about 12x12 section formed in the ballast tank.
There are two thru-hull fittings, one for the Speed transducer and one for the Depth transducer.

Russ

Russ Johnson
2005 C250WB Hull 793

doublereefed
Navigator

Members Avatar

167 Posts

Response Posted - 07/30/2017 : 09:44:24

Thanks Russ, I'll take a look...

'95 C250 WB #61
Midway, UT

Topic

New Topic

Topic Locked

Printer Friendly

Jump To:

Association Forum

Notice: The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.