Re: Re: [PSUBS-MAILIST] external Motors for depths of 1000ft

["Captain Nemo" <vulcania@hawaii.rr.com>]

Roger,

You ever heard of something techs call by the slang term "Jesus Oil"?  Some
kind of transformer oil, maybe?  If so, know what it's real name is, and /
or who sells it?

Dave has his stuff for sale on eBay; and he's scarcer than honest
politicians these days.  May be downsizing his operation.  All I can say is
keep trying.  Casey's available at trollingmotorparts.com, though.

Biodegradable?  Hmmmm....interesting.  Mind sharing with us what it is?
(Would it be something we could cook with?)

Thanks for the info about the props.  Helpful.

Pat


----- Original Message -----
From: <rjune@fuse.net>
To: <personal_submersibles@psubs.org>
Sent: Wednesday, June 19, 2002 10:48 AM
Subject: Re: Re: [PSUBS-MAILIST] external Motors for depths of 1000ft


> Rob, you are basically correct.
>
> 1. If the correct oil is used (low viscosity and dielectric)
>     there is no appreciable reduction in rpm.  By the way
>     the oil that I use is Biodegradable.
>
> 2. Is Dave at DC Marine still around ???
>     I've  tried to locate him, with no luck.
>
> 3. The Aluminum prop that I sell, should only
>     be used on the 80# and 107# motors as it will
>     burn up the smaller motors.
>
>
> >
> > From: "Captain Nemo" <vulcania@hawaii.rr.com>
> > Date: 2002/06/19 Wed PM 04:17:07 EDT
> > To: <personal_submersibles@psubs.org>
> > Subject: Re: [PSUBS-MAILIST] external Motors for depths of 1000ft
> >
> > Rob,
> >
> > I don't have an exact number, but drag-induced RPM reduction on the
armature
> > isn't much at all due to it's shape.  A guy to ask might be Dave at DC
> > Marine, or Casey at trollingmotorparts.com.
> >
> > BTW: Casey is presently selling the complete MK Riptide 101# 36VDC unit
for
> > about $550.  This is a saltwater motor, and for this price you get the
> > factory potentiometer, prop, the whole tamale.
> >
> > MK's are factory rated to one additional atmosphere: 33FSW.  People have
> > been using them to 100 feet with a 95% success rate, but the company
won't
> > cosign that.  One tech I know of is modifying the motors to work
> > uncompensated at 300 feet by polishing the shaft and matching it to a
better
> > seal; I've got no info on the success / failure rate of those
modifications,
> > but he says people have been using them for a while and didn't mention
any
> > complaints.  One thing, though; if you open the case to modify the
innards,
> > you need to reassemble it correctly: time the brushes and torque the
covers
> > down properly.  Otherwise, she no runna so well.....
> >
> > Regarding props: one problem MK had years back with the 4HP (just a
name,
> > not a horsepower rating) occurred when they went from the plastic
weedwacker
> > to the an aluminum prop.  Large numbers of burned out motors started
coming
> > back the shop; MK finally returned to the original prop.  Something to
keep
> > in mind when thinking about modifying the prop arrangement from what the
> > design engineers originally decided on.  Not saying it can't be done,
but
> > possible overheating is something to be aware of.
> >
> > The pressure compensation of any of these motors should make them
> > serviceable at homebuilt-sensible depths.  If in doubt about oil
> > compensation, you could always use air.
> >
> > Pat
> >
> >
> > From: "Rob Innes" <innespace@jett.net>
> > To: <personal_submersibles@psubs.org>
> > Sent: Wednesday, June 19, 2002 10:03 AM
> > Subject: Re: [PSUBS-MAILIST] external Motors for depths of 1000ft
> >
> >
> > > Does anyone know how much resistance is caused on the trolling motors
by
> > > filling them with the oil? Approximately how much thrust could expect
to
> > be
> > > lost on a Motorguide 107lb thrust unit? Has anyone fitted one or more
of
> > these
> > > motors to a sub or DPV?  I'd be very interested in the results
> > >
> > > Rob Innes
> > >
> > >
> > >
> >
> >
> >
>
> Roger June
> REJ and Company
> rjune@fuse.net
> 513-300-1189
>
>