NASA Clipper depth transducer oil??

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tonygibbs

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Hello all, I broke the plastic pipe where the transducer fits from the hull. Noticed that there was some kind of oil in the bilge. Easy enough to re-attach tho' I've been told that ordinary vegetable oil would be ok to use. Is this correct, if not what oil should I use?
 
Easiest way is to clean the oil off the bilge, throw the pipe away and stick the transducer on with a gob of silicone, epoxy or polyester. I used some of the green fiberglass filler which comes in a tube.
 
I believe the recomendation from Nasa is "mineral oil". That got a rather bemused look from my local chemist who found several possibles from a Google search! In reality i think most people use whatever cooking oil they have on board. The important thing is not to use any synthetic stuff which might attack the plastic.

Rob.
 
baby oil is good. Dont use olive oil though, it cloudys up in low temps .. A gob of silicon works carefull no bubbles! though .If you want to test for position ie bubles in GRP can cause problems you can use a plastic bag with water, wedge it in place to test the position works . Silicon can be cut if needs must to move.Epoxy or polyester make it hard to move.
 
GrahamM376 said:
Easiest way is to clean the oil off the bilge, throw the pipe away and stick the transducer on with a gob of silicone, epoxy or polyester. I used some of the green fiberglass filler which comes in a tube.
Click to expand...

I have seen silicone recommended several times and attached mine like that, but got lots of odd readings. I asked Nasa about this and they told me that Silicone is elastic, so absorbs some of the energy of the ultrasound, thereby reducing sensitivity. I changed to the "oil tube" arrangement (more faff, I grant you) and the depth readings seem more reliable. I was too chicken to epoxy the transducer to the hull in case I made a mistake (no coming back from that).

+1 for vegetable oil. I used rape seed oil from the kitchen.
 
While on this instrument...
I like the look of the nice big display and it matches an existing GPS repeater.
But I have Airmar instruments now feeding an ST30 Bidata.
Are my existing instruments compatible with the NASA head unit/display?
 
colvic987 said:
caster oil is the preferred oil as per the nasa info, you can buy it from a pharmacy is small quantities
Click to expand...

castor oil been in the mounting tube for my ( Seafarer) transducer quite happily for 35 years

(nb caster sugar but castor oil)
 
tonygibbs said:
Hello all, I broke the plastic pipe where the transducer fits from the hull. Noticed that there was some kind of oil in the bilge. Easy enough to re-attach tho' I've been told that ordinary vegetable oil would be ok to use. Is this correct, if not what oil should I use?
Click to expand...

I have used vegetable oil in a plastic pipe epoxied to the hull for the last 2 years with great readings and no problems

Hope this helps

Les
 
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