transducer attachment

[thataway]

A heat gun will not give enough heat to "flash" the Starboard. But you can use any gas burner (don't tell the Admiral--and be careful!). Everyone needs a propane torch! (Amoungst about 1000 other "tools").

[NORO LIM]

I have another question regarding transducer mounting. My boat spends much of its time in the water. Aside from struggling with critters and slime on the engine brackets , dealing with growth on the transducer is about the biggest PITA there is. I've been toying for years with the idea of some sort of transducer mount that allows the unit to be raised out of the water when not in use, but affords a quick and easy way to lower the unit securely to its working location.

I just came across this: http://www.transducersaverplus.com/transducer-mount.html

Has anyone tried this or a similar product, or designed their own sliding mount? Pitfalls? Suggestions?

[jerry97230]

I glued two Weld Mount studs on the hull and then tapped a small piece of stainless for the transducer and drilled to holes for the studs and bolted it on.
My boat is in the water and I do not have a trailer so this was the best method for me. Seems to work just fine, no holes in hull,i can remove the transducer at any time, and removing the studs should not be a big deal.
Jerry C Nile

[thataway]

There are a lot of bass fishermen who have transducers mounted on the trolling motor in the bow. These come out of the water. I had one boat where the previous owner had mounted the transducer on a 8 foot pole, which swung from the bow sprit down into the water. I owned another boat which had a wooden version of the device you found.

I don't see any reason why it would not work. I have a swim step on one side of the 22, and a mount for the kicker/dinghy motor on the other (stb side, where the transducer is typically mounted.)

This device should work fine--just the issue of taking it up and down--and that may be not an issue for you. There are a number of other ways of mounting a transducer on an arm which would swing down.

[kennharriet]

I used a scrap piece of corian countertop material, epoxied to the transom, then drilled for the transducer mount. The corian material is soft enough to cut with a table saw into a block of the right size. If you would like a block, send me your measurements and I'll get in the mail to you.

[NORO LIM]

Thanks for the helpful responses and the generous offer. I think I'm leaning toward giving the sliding mount a try.

Now, as I ponder my winter projects, I find my OCD symmetry affliction urging me to try mounting the transducer between my twin engines, right on the center line of the boat. (Isn't the thought of that visual balance just irresistible?)

OTOH, the sounder has worked great with the transducer where it's been for 7 years, on the starboard side of the transom, and my neurotic attachment to the "If-it-ain't-broke . . ." principle gives me the heebie-jeebies when I contemplate changing anything.

Has anyone with twin engines on a C-Dory or Venture hull tried center mounting their transducer? Dare I do it?

[Sunbeam]

I can't speak to twins (although yes, the symmetry is very appealing!), but I did notice - when I went to mount my transducer - that the instructions recommended to put it on the starboard side of the prop if you can. I guess the effects of the prop make the port side the "bad" semi-circle. So I suppose it's possible that you would get that effect from the starboard engine with the transducer in the center (?).

Will be interesting to hear if other twins folks have good luck with it in the center.

[Montana Kev]

To mount my transducer - I used Starboard with 5200, 3 years ago, no screws, 3 months a year in a slip/in the water, 20 below zero in the winter and it's tight as can be. Like Dr. Bob advised, I cut groves in the back of the starboard using a table saw. Then I put a layer of 5200 on the grooved starboard like laying tile, I let the 5200 dry. Then I roughed up the dried 5200 with sand paper and applied another layer of 5200 and applied the starboard to the boat. I clamped it for 24 hours. Works great.

Kevin

[NORO LIM]

[thataway]

Yes, the reason that it is recommended to put the transducer on the stb side is because of the down stroke of the blades on the right side of the prop, and less turbulence on that side. In the center, especially with counter rotating props, would be the worse place for the transducer.

[halibut taco]

[NORO LIM]

Well, two discoveries from the Furuno site's AIRMAR manuals for installing transducers:

1. Regarding placement of a transducer:

Boat Types
•
Single drive
—Mount a minimum of 15cm (6") beyond the swing radius of the propeller (see Figure 1).
•
Twin drive
—Mount between the drives a minimum of 15cm (6") beyond the swing radius of the propeller.
•
Trim tabs
—Mount inside the trim tab, space permitting.


2. Regarding a sliding mount that can lift the transducer out of the water between uses:

CAUTION:
CHIRP transducer—Always operate the transducer in water. Operating in air will allow the transducer to overheat resulting in failure



First, regarding the placement - I'm pretty happy with the starboard side placement I'm using now, and I don't know how optimal this recommendation may be for twin engines mounted as closely together as they are on a C-Dory or Venture.

Second, regarding a sliding mount - the caution against out-of-water operation is only academic as far as I'm concerned. The warning apparently applies only to CHIRP technology transducers - I guess you really don't want to forget to lower a CHIRP transducer into the water before you turn the sounder on. As far as I know, AIRMAR makes only one transom mount CHIRP transducer (TM 265). I'm looking at either a 258 or 260.

I doubt these discoveries will influence my decisions, but thought others might find the information useful or interesting.

[thataway]

Any of the transducers will heat up some when run out of water. The higher the power, the more it will heat up, and more danger of damage to the transducer, but most of the lower power units most likely will not be damaged. The CHIRP runs a number of frequencies--and has to have more heat dissipation.

"Airmar’s B265LH, for instance, includes eight ceramics: A large one, nearly three inches in diameter, handles the high frequency range while a cluster of seven one-inch ceramics handles the lower frequencies.

But there’s more to a CHIRP transducer than high-tech ceramics. It’s a simple fact of life that whenever you pass any kind of energy through anything it gets turned into heat, and a transducer is no different. One old problem that has been brought back to the surface by CHIRP is that the impedance of a transducer—its tendency to oppose the flow of electricity—varies depending on the frequency at which it’s operating. That’s important because if the impedance drops, more power flows through the transducer, making it more likely to overheat and more likely, in the long term, to degrade the piezoelectric characteristics of the ceramic."

Also the CHIRP transom mount cannot be installed as a in the hull mount as a standard transom transducer is.

[Sunbeam]

When they recommend mounting the transducer in between twin drives, I wonder if that is because they presume you would not have room to mount to the side (because most twins are further apart?). Maybe the 22/25 don't have room either though - I don't know. Wonder if they would still recommend the center in a case where there was room to go to the starboard side of the starboard engine.

I had a problem with my (new) transducer on Powell. I'd be going along fine (high speed, low speed, rough water, smooth...) and all of a sudden I'd get the digital reading of 2.3' and a shallow water alarm (in all kinds of depths). Sometimes the fishfinder part of the reading would stay at the real reading, and sometimes they would both be at 2.3' Eventually it would fix itself but I could not figure out any consistent reason.

Finally I figured out that it would sometimes "fix" itself if I stopped, reversed relatively hard, then went forward again. But not always.

I had mounted it in the center of the up/down adjustment slots, so tried changing those. Down was no help; up seemed to help slightly. I had also mounted it just the amount they recommend outside the prop circle, but no more (because I was advised that the trim tabs affect it even more than the prop). However, since reversing and then going forward seems to fix it sometimes, I'm thinking of trying moving it further to starboard (away from prop; toward starboard trim tab). The problem occurs just as often at hull speed as on plane, and the depth sounder works great on plane (when it does work), so it doesn't seem to be the usual "lose signal when going fast" problem. I have not yet contacted Airmar.

I removed the core from the after sump, so I could mount a shoot-through-the-hull transducer there, but I like the water temp and speed from the transom mounted one.

Sunbeam

PS: Somewhat in the spirit of the thread: I considered using Weld Mounts to mount the Starboard backing board (I have used them in many other places on the boat), but in one of those "probably a horse apiece" decisions, went another way. I wasn't sure if adhering them to the gelcoat would be strong enough (dependent on the bond of small circles of gelcoat, ultimately), and though I considered removing circles of gelcoat for the WM's, decided not to (although as I said, it was sort of a horse apiece). Anyway, I ultimately removed the transom core from a largish area (behind the gelcoat/fiberglass surface, which only has a smallish hole in it), filled with thickened epoxy, and then drilled and tapped for flat-headed bronze machine screws (that run through the Starboard block). Then I tapped the block for the transducer screws.

PPS: Interesting about not running some transducers out of the water; I had wondered about that (but I just have the P66 triducer, not any kind of CHIRP one).

[beermanPDX]