Re: [PSUBS-MAILIST] Pressure compensation

["Dale" <heinzind@cadvision.com>]

-----Original Message-----
From: Marsee Skidmore <heyred@email.msn.com>
To: personal_submersibles@psubs.org <personal_submersibles@psubs.org>
Date: Tuesday, August 15, 2000 10:27 PM
Subject: Re: [PSUBS-MAILIST] Pressure compensation


>Light machine oil used to be whale oil. After they started using kerosene
>(sp?) for lamps and spring steel for corsets, it was about the only thing
>whales were good for. Then somebody discovered that jojoba bean oil was a
>dead ringer for whale oil. Now the only thing that whales are good for is
>cat food. - Joe
>
>----- Original Message -----
>From: <TeslaTony@aol.com>
>To: <personal_submersibles@psubs.org>
>Sent: Saturday, August 12, 2000 9:08 AM
>Subject: Re: [PSUBS-MAILIST] Pressure compensation
>
>
>> In a message dated 8/11/00 9:23:43 PM Pacific Daylight Time,
>> protek@shreve.net writes:
>>
>> > Jon,
>> >       You're right in that the mentioned method is a much better way of
>> >  compensating.  I wonder if anyone has ever been successful at using a
>low
>> >  viscosity oil in a trolling motor.  It would be an interesting
>experiment
>> >  in the direction of a low cost compensated thruster.  It almost makes
>me
>> >  want to go get a trolling motor and experiment.  I wonder if the
>armature
>> >  would have too much drag against the oil and how much power you would
>> loose
>> >  in the process.  I would think that cooling would not be a big
problem.
>I
>> >  would suspect that real thrusters for submersibles that are
compensated
>in
>> >  this way have special armatures.  Probably the same oil used in
>> submersible
>> >  pump applications would work.
>> >
>> >  GB
>> A good oil would be that oil that is used to lube guns and sewing
>machines,
>> it has a pretty low viscosity, lubes all the moving parts, fairly easy to
>get
>> (I dare you to find a hardware store that doesn't carry the stuff) and
>should
>> seal anything that arcs to prevent shorts. The biggest drawback would be
>the
>> quantities that you could buy it in since the biggest I have seen has
been
>4
>> oz. (although you probably could get bigger).
>>
>> Anthony
>>
>>
>
>
>
>I have talked to someone, who uses 24volt minkota trolling motors, and
fills them with baby oil.  He says this works fairly well, and the losses
are minimal with the 24 volt motors, however they dont work as well at lower
voltages, like 12 volts.. the only problem is they always seep a tiny bit of
oil I guess, and he says its messy..the 24 volt motors use brushes, and he
says that sometimes you have to increase the spring pressure on the brushes,
but that does not cause any premature wear problems..seems to work for him..

and just a side note, he says spray the inside of the motor with WD40 or
similar, if you are going to pressure compensate them..that way, any water,
or condensation will do minimal damage..

dale.