transducer/help

tango1
08 August 2007, 21:36
can anyone tell me how to get accurate info when at speed as i have never had this with any rib where it is mounted on the stern. i dont want to have to put it on the skin or through the hull.

alt
08 August 2007, 22:12
can anyone tell me how to get accurate info when at speed as i have never had this with any rib where it is mounted on the stern. i dont want to have to put it on the skin or through the hull.

Having the same problem with my sports cruiser. Solution is to install an in-hull transducer. I was told you can use the existing transom mounted one but for the sake of a few dollars i'd just buy one from the states. I have the advantage in the sports cruiser as there is nothing between the bilge and the water (apart from timber and GRP obviously), not too sure how you'd manage it on the RIB

codprawn
08 August 2007, 22:13
Silicone it into the hull so I have been told!!!

alt
08 August 2007, 22:14
Silicone it into the hull so I have been told!!!

Yup, heard that myself, making sure there is no air bubbles. However isin't there a hollow between the floor/underside of the hull on RIB's?

tango1
08 August 2007, 22:19
the deck is sealed i used silicon on the hard boat i had and it was perfect. but on a rib this is not the best option.

M Humphray
09 August 2007, 07:15
The local Rib dealer over here, uses "Marine Epoxy", from Plastic Padding, to affix the transducer to the floor of the hull.

ScottyDog
09 August 2007, 07:32
Just to clarify:

Can you get to the inside of the hull near the centre/keel line close to the stern ? If not then I understand your problem but after reading several people's reluctance to use a transducer bonded to the hull I have to say it was a great quick fix for me.

I had a transom mounted transducer which gave me water temp. and water speed but whenever travelling above 5 knots or so it would lose the ability to give the depth. I moved it around but could not find a suitable, non turbulent place. I got a Airmar 'puck' type unit from JG Tech for £80 which was a doodle to fit, just Sikaflex the flange on the tube then fill with castor oil, £1 from chemist then insert transducer - now it works at all speeds and I can live without the water temp/speed. Airmar make a wide range of transducers to suit a variety of head units.

If you need to try many positions for the transom mount unit I can only suggest mounting a strip of acetal/nylon/wood etc along the bottom edge and then you can move it around all the time to find a suitable place without riddling the transom with holes. Just resin up any redundant holes after finding a permanent home for the transducer.

DJL
09 August 2007, 12:17
If you're stuck with transom mounting then play around with different angles/heights. I personally find you need to increase the projection below the hull and angle by about twice that specified in the instructions.


Make sure the front of the transducer is higher than the back - roughly a 10/15 degree angle
Make sure the front of the transducer is at least 5mm below the hull of the boat.

tango1
09 August 2007, 21:47
i think everyone here is correct,but i have the transum mount at the moment and i ill try moveing it a little but i really dont want to go to the bother of cutting the deck to get to the hull. many thanks to all.

Biggles
09 August 2007, 21:52
Tango,

What boat is it and you got any pics of the transom well or rear deck area.

Regards NR.

Spike
09 August 2007, 23:46
Hi Tango1,
Do you not have a well/sump in the stern of the boat where the bilge pump does/should fit?

Biggles
10 August 2007, 01:28
Hi Tango1,
Do you not have a well/sump in the stern of the boat where the bilge pump does/should fit?

Mike,

Thats what I was hoping we would get a picture of then we should be able to on from their. If he's got a sump then it won't be a problem. Nick R.

tango1
12 August 2007, 20:15
i will upload a pic in the next 24hrs. i dont have sump its very small well if you can call it that. the boat is a delta dash.

tango1
19 August 2007, 21:30
sorry for the wait!

alt
19 August 2007, 21:45
sorry for the wait!

That's way too high! The transducer needs to be under the bottom of the transom

JABS
19 August 2007, 21:45
IMHO the transducer is way too high.

It needs to sit in a clean flow area. We have a set up with Lowrance kit and, after calibration, it is reliable up to our max speed.

I know it means extra holes, but it must go lower. That is assuming the hull is clean. Also, try to avoid areas near chines.

Try some structural adhesive pads first. 3M make them and you can buy them from such as Staples. If it works, drill some holes!