Mineral Oil for Transducer

Talulah

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When installing an in hull transducer the instructions call for mineral oil to fill the void between the sensor and the hull.
What is mineral oil? Chemists don't know what I am talking about. Can I use engine oil?
Thanks in advance.
 

graham

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I think the makers instructions for my latest one call for Castor oil but I have been running it in cooking oil for the last 5 years ,no problems.
 

Steve_N

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Olive oil goes all thick and v. lumpy well above 0 degrees C - I don't know, but I'd imagine that wouldn't be ideal. False echoes perhaps if sailing in cold waters?
 

bonny

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I used araldite to bond my in hull puck to the bottom. Worked fine for 4 years with a Navman fish400 fishfinder and was getting echoes down to the limit of the fishfinder 200m in North Channel near Mull of Galloway.

No maintenance required.

I had previously tried oil some years before in a different boat (baby oil) but finished up with a mess and vowed never to go down that route again.
 
G

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Castor oil .....

Local Chemist in 250ml bottles. I always buy 2 .... use one, keep other for top up.

If you have a leaky tube and the oil gose all sticky and brown gungey !! ..... take out transducer, break out tube from bonding. Wipe up mess as best you can with paper towels etc. With chisel clean up the bonding left on hull that held the tube, removing back to original hull. Then spray liberally with oven cleaner. Let it foam and lift all the crud. Wipe away excess and then rinse with clean fresh water. Dry off with hair dryer and you have cleanest best surface to bond to.
Replace cleaned tube into palce and tack in place with fast set epoxy. Now build up polyester resin filler around the tube smoothing into a rising gradient fillet to hold the tube firmly.
Once all set - pour in castor oil. Slowly press in transducer allowing oil to squeeze past transducer.
 

tyce

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Re: Castor oil .....

mineral oil is just standard engine oil i.e. not synthetic/ semi synthetic, but to be honest bedding the transducer in silicon sealant works just as well as anything, and unlike araldite and similar it is not permanent and can be moved if required
 

simonfraser

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Re: Castor oil .....

you just need to exclude the air, bits in the oil? i hope the water under your hull is nice and clean :)
 

JKay

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Re: Castor oil .....

just done it the silicone method works 100%

no mess no oil thanks to this forum /forums/images/graemlins/wink.gif

cheers Joe
 

EdEssery

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Try Ultrasound Gel - available from your local chemist. Less messy than any of the oils and explicitly designed for the job you are trying to do....
 

oldsaltoz

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G'day Edward,

You only need to add oil if you plan to suspend the transducer so that it still points at the bottom when heeled.

Most transducers are bonded to the inside of glass hulls. This will give the depth at the angle of heel so you need to be aware of this in shoaling waters, reduce sail / heel for a better reading.

Most oils will work, you only need to exclude and air from the business end of the transducer.

If you are planning on hanging / suspending it, make sure the oil is contained when heeling at maximum (wet mast).

If you are bonding; First put the transponder in a clear plastic bag, try it in the location you plan to fix it by wetting the hull surface with water, if ok. Then make sure you have enough space, a standing transducer tales up a lot of space. a small off-cut of PVC pipe 2" or so, held in place with plasticine or other temporary sealant, make up a wire stand to temporarily hang it from and half fill with epoxy resin, lower the transducer in at a steep angle and turn it very slowly to avoid and air being trapped; hang on the wire frame and it cure overnight.

Andavagoodweekend...........
 

tim3057

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Re: Castor oil .....

Am I missing something here? I thought the transducer just slotted into the plastic housing/tube and then tighten the ring thingy to hold it in place? It seems to have an 0-ring to make the seal complete so why all this talk of oil?
 

Ships_Cat

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Re: Castor oil .....

On plastic boats (as long as the bottom is not of sandwich construction) the depth transducer can often just be fitted against the inside of the hull with oil or whatever between the transducer and the inside of the hull to ensure acoustic conductivity.

Those of us with boats made of proper /forums/images/graemlins/smile.gif materials such as wood or metal cannot do that, nor can plastic boats if the bottom is sandwich construction, unless very thin. So is fitted through the hull as I think you are alluding to.

Sorry if I have misinterpreted your query and you knew all that already.

John
 
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