How deep am I???

Mark · Jun 4, 2002

I recently bought and installed a depth finder in my '83 Mac 25. The transducer is a "thru hull" so I glued it in. I removed the access port (aft) in the v-berth, removed the numerous jigsaw puzzle foam blocks (that I can not get all back in to save my life) and epoxy mounted the transducer to the hull. It works like a dream while in the slip and while motoring out of port, but drops in and out while sailing. I am guessing that I am, while heeling or bouncing through waves, picking the transducer out of the water. I assumed that the loaction I chose would be ideal as it does not suffer the turbulent effects of the keel, etc. but I guess I was wrong. Any suggestions as to better placement of the transducer would be appreciated. I will not pop a hole in my hull and do not want to do transom mount...I don't want to know how deep the water is where I have been already!!-Markp.s. Oh yeah, anyone have any idea what the rope is that seems to stradle the keel. A knot on either side of the keel cable at the rear bulkhead and a loop passthrough at the front bulkhead (just aft of where I installed the xducer above). My engineering mind can see no reasonable explanation for this rope...help please!!!

Marty · Jun 9, 2002

Transducer placement

I also have a thru hull transducer on my boat. Like you, I did not want to drill a hole, or mount it on the transom. So after some time at a local book store, I found my answer. I took a short length of pvc pipe and glued(epoxied) it to the flat part of the bilge right next to the keel box. Then you cut a slit about 1 inch in length to allow the cable from the 'ducer to the display module to exit. Next, place the 'ducer in the pipe, face down, and fill it with water. Screw on the pvc cap and you're in business. It will only work when there is continuity between the 'ducer and the water under your hull. Also, by not gluing the 'ducer in place, it's easy to remove for maintenance or replacement. Give it a shot and happy sailing. Marty

Mike · Jun 10, 2002

That little rope.

It sounds to me like you have a pull rope running fore/aft. If so, someone was thinking ahead. When running wire for fore deck lights, bow lights or even flexable plastic tubing for water, etc., you can use the pull rope to pull the wire or tubing from under the cockpit to inside the V-berth. Make sure it is a pull rope and not the wire for your bow light. If it is a pull rope and you use it, pull a new rope along with whatever you are pulling so you can have one for future use.Mike

Mark · Jun 12, 2002

Roped into that one

Mike,I would have thought the same except for a few things... 1.) there are identical equally spaced knots either side of the keel cable 2.)the "loop around" side under the v-berth looks like it has been designed in and the rope is tight against the vertical panel 3.)the only electrical is to the bow light, is run along the stbd side and looks to be factory original and 4.) since I have two complete foam blocks that just will not go back in the space under the v-berth I doubt that anyone has ever been in there since the hull and liner were mated.I have had confirmation that other Mac 25 owners of around the same year have similar ropes. One speculation, which I tend to think is the case, is that it was somehow used in the fiberglass layup process to hold something in place.Thanks for the thought though...I have just been using my telescoping washdown brush pole to cram wires from one end to the other.-Mark

Mark · Jun 12, 2002

Stove pipe

Marty,Sounds like you are very close to the keel. Do you have any problems with false returns from the keel itself or even dropout from turbulence? Also, do you have to monitor the water level in your tube? I would guess that due to the slit for the wire exit, the water level would be subject to evaporation.-Mark

Marty · Jun 25, 2002

Transducer turbulance

Mark, I've not had a problem with turbulance or false readings either. You do have to check the water level in the PVC to be sure the 'ducer is totally covered. I do this as part of the "checklist for departure". It's very simple to do and takes all of about 30 seconds. Also, the 'ducer is positioned well aft of the pivot area of the keel so that I get good readings when heeled over.