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Re: [PSUBS-MAILIST] thru hull fittings
Machining internal O ring Goroves is not hard at all.
and measuring for gland depth is fairly easy ,,can be
as simple as useing a bear ball with regular
micrometers..If you like more details id be happy to
share them
john
--- Brian Cox <ojaibees@ojai.net> wrote:
> Ian,
> It is not overly difficult, you might
> have to make your own cutting tool to do it. I've
> done it . but it is very hard to inspect. You have
> to make the tool so that it can reach inside the
> hole to machine the groove.
>
> Brian
> ----- Original Message -----
> From: "irox" <irox@ix.netcom.com>
> To: <personal_submersibles@psubs.org>
> Sent: Sunday, February 29, 2004 11:34 AM
> Subject: Re: [PSUBS-MAILIST] thru hull fittings
>
>
> >
> > Hi,
> >
> > I was wondering, how do you get the grooves for
> the O-rings on the inside
> > of the housing?
> >
> > Is this done by some special metal lath tools or
> does it require a special
> > lath to do this?
> >
> > Thanks in advanced.
> >
> > Ian.
> >
> > -----Original Message-----
> > From: "Dan H." <jmachine@adelphia.net>
> > Sent: Feb 29, 2004 10:08 AM
> > To: personal_submersibles@psubs.org
> > Subject: Re: [PSUBS-MAILIST] thru hull fittings
> >
> > Brian,
> > No, no Not at all.
> >
> > Either O-rings on the shaft, or O-rings in the
> housing will work. As far as
> > leaking, it's the shaft to housing clearance and
> the proper groove depth
> > that matter. And yes, hydraulic applications do
> sometimes use O-rings in a
> > shaft but not as a rule. If the shaft is the
> critical component, the O-ring
> > grooves are in the housing. Grooves in a shaft
> weaken it.
> >
> > Maybe I didn't explain myself well before. What I
> meant by my earlier
> > posting was, if you groove the shaft, the groove
> diameter, minis a little
> > factored in for the stress risers created by the
> groove, becomes the working
> > diameter of the shaft. The weakest point! A
> groove does create stress
> > riser. If you break a shaft with grooves in it,
> it will always fail in one
> > corner of a groove. A properly designed O-ring
> groove has small radii in
> > it's corners, but still it's a week spot. If you
> take the same shaft size,
> > but put the O-ring in the housing, you can design
> around the full shaft
> > diameter.
> >
> > I tried to keep my shaft diameters from getting
> larger then needed because,
> > as a shaft get larger it takes more force to turn
> when your deep. At 400
> > feet a one inch shaft has 160 pounds of force
> pushing in on it. That
> > creates friction that you have to overcome to turn
> it.
> >
> > Dan H.
> > ----- Original Message -----
> > From: "Brian Cox" <ojaibees@ojai.net>
> > To: <personal_submersibles@psubs.org>
> > Sent: Sunday, February 29, 2004 12:14 PM
> > Subject: Re: [PSUBS-MAILIST] thru hull fittings
> >
> >
> > > Hi Dan,
> > > I knew that would draw a
> response ! I really don't
> > follow the reasoning on this. I simply do not
> understand what you are
> > saying. Don't most hydraulics have the O rings on
> the the shaft and with
> > those we're talking 3000 psi. If I had the O
> rings on the shaft are you
> > saying that I would not be able to turn the shaft?
> And the O ring would
> > leak because there is more stress on the corners
> of the O ring grooves? I
> > don't get it ! Sorry to be so difficult and
> annoying !
> > >
> > > Brian
> > > ----- Original Message -----
> > > From: "Dan H." <jmachine@adelphia.net>
> > > To: <personal_submersibles@psubs.org>
> > > Sent: Sunday, February 29, 2004 5:19 AM
> > > Subject: Re: [PSUBS-MAILIST] thru hull fittings
> > >
> > >
> > > > Brian,
> > > > O-rings on the shaft create areas of higher
> stress in the corners of the
> > > > O-ring grooves. Also your shaft diameter is
> the area that the sea is
> > acting
> > > > on when calculating how much force is pushing
> inward on the shaft. At
> > depth
> > > > that force creates some resistance to turning.
> But, for sheer, tension
> > and
> > > > compression, your shaft diameter is only the
> root to the O-ring groove
> > minus
> > > > a bit for the stress risers in the groove
> corners.
> > > >
> > > > It's a bit more difficult putting the O-rings
> in the thru hull, but the
> > > > shaft in one size and most efficient.
> > > >
> > > > Dan H.
> > > > ----- Original Message -----
> > > > From: "Brian Cox" <ojaibees@ojai.net>
> > > > To: <personal_submersibles@psubs.org>
> > > > Sent: Saturday, February 28, 2004 6:54 PM
> > > > Subject: Re: [PSUBS-MAILIST] thru hull
> fittings
> > > >
> > > >
> > > > > Dan, thanks for the insite, I'll probably
> go bigger on the drop
> > weight.
> > > > My "O" rings are going to be on the shaft.
> > > > >
> > > > > Brian
> > > > > ----- Original Message -----
> > > > > From: "Dan H." <jmachine@adelphia.net>
> > > > > To: <personal_submersibles@psubs.org>
> > > > > Sent: Saturday, February 28, 2004 5:50 AM
> > > > > Subject: Re: [PSUBS-MAILIST] thru hull
> fittings
> > > > >
> > > > >
> > > > > > Brian,
> > > > > >
> > > > > > You sound like your on the right track
> with your through hulls. One
> > > > thing
> > > > > > to consider with your drop weight through
> hulls is, how your going
> > to
> > > > attach
> > > > > > the handle inside the sub. If your going
> to drill through the shaft
> > you
> > > > may
> > > > > > want to consider a shaft larger then a
> half inch since it's holding
> > the
> > > > drop
> > > > > > weight and will get yanked through the
> hull if it breaks or of the
> > bolt
> > > > > > shears. When making mine, I was
> visualizing the drop banging up and
> > > > down on
> > > > > > it's shaft while tailoring down the road.
> Then I want to depend it
> > to
> > > > hold
> > > > > > the weight when diving.
> > > > > >
> > > > > > I had a bit of trouble with the through
> hulls necking down in the
> > weld
> > > > area
> > > > > > but cured the problem with a hand reamer
> after welding. Use two
> > > > O-rings,
> > > > > > one near each end, for double protection
> and then you won't be
> > welding
> > > > or
> > > > > > reaming where they will be.
> > > > > >
> > > > > > Dan H.
> > > > > >
> > > > > >
> > > > > > ----- Original Message -----
> > > > > > From: "Brian Cox" <ojaibees@ojai.net>
>
=== message truncated ===
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