> Thanks Vance & Phil,
> Good to have living sub encyclopedias in the group.
> Carsten, am not sure what dynamite bolts are but it sounds like that if
> you bought the big ones you might be sinking rather than floating.
> Alan
> ----- Original Message -----
> From: Phil Nuytten
> To:
personal_submersibles@psubs.org> Sent: Monday, January 16, 2012 8:15 AM
> Subject: Re: [PSUBS-MAILIST] electromagnetic drop weight mechanism
>
>
> All:
> I agree completely with Vance on the electromag weight drop question. The rotation cam-over-center or latch-pivot operated by a
> thru' hull shaft has certainly stood the test of time. There are a number of variations including a layered weight plates system
> with alternating keyed slots so you can drop just enough to make you buoyant and so on - but I believe the KISS principal very much
> applies here.
> Phil
> ----- Original Message -----
> From:
vbra676539@aol.com> To:
personal_submersibles@psubs.org
> Sent: Sunday, January 15, 2012 6:03 AM
> Subject: Re: [PSUBS-MAILIST] electromagnetic drop weight mechanism
>
>
> There are substantially more cons than pros here. Many of the deep vehicles and early attempts used this, including the old Deep
> Jeep, Alvin, and the Trieste. Read up on any of them and you will find instances where an unexplained short dumped everything and
> sent them to the surface. Expensive and wasteful is what it is. Especially Trieste, which had its BATTERIES held on sloping rails
> (they were deck mounted, originally) and lost them ALL due to a very minor short circuit in the cabin. Lost them all at 15,000 feet,
> that is. My friend Mike Stahle was the chief pilot and then crew commander for that thing, and they hated those electromagnets.
> Hated them! Necessary for them, of course, but for us, a penetrator is just too dead easy to install--and bullet proof. Turn handle,
> drop weights. Don't turn handle, take weights home. Simple.
> Vance
>
>
>
>
> -----Original Message-----
> From: Alan James <
alanjames@xtra.co.nz>
> To: personal_submersibles <
personal_submersibles@psubs.org>
> Sent: Sat, Jan 14, 2012 8:46 pm
> Subject: [PSUBS-MAILIST] electromagnetic drop weight mechanism
>
>
> Hi all,
> Haven't designed my drop weight mechanism yet, but are toying with the
> idea of using electromagnets.
> Was looking at some gate holding magnets that had a holding force of 1200 lb &
> a draw of only 500mA off 12V. They were a tad expensive so will look for an alternative.
> The positives I see are that the system would be easy to put together, (possibly with multiple
> magnets for making the weights more manageable), & you could drop your
> weights very quickly. The negatives are you would not want to turn the power off before
> you were on land & you would need a system of locking the weights in place for transport
> or alternatively remove them.
> Is this system used elsewhere, any thoughts??
> Alan
>