[PSUBS-MAILIST] PSUBS manipulator

[Alan via Personal_Submersibles]

Just found the photo below of a Lenco actuator that got water in through
a seal. I would guess it is one of the main body seals. Perhaps the body
flexes a bit under load, or the seal came out of its groove on assembly.
Anyway something to be aware of during assembly.
Alan


> On 23/09/2020, at 12:16 PM, Alan via Personal_Submersibles <personal_submersibles at psubs.org> wrote:
> 
> Thanks Alec & Hank.
> I found the diagram below that doesn't show any switches.
> I like the idea of air compensating them, perhaps with an over pressure from
> a regulator as Cliff is using on his thrusters.
> The two shaft O-rings are as per the Minnkota, with the outer O-ring doomed
> to fail when the pressure gets high enough. If there was an overpressure  the 
> inner O-ring would fail first (hopefully)  leaving the cavity between the two with air.
> Or is it filled with Greece?
> Alan
> <image1.PNG>
> 
> 
>> On 23/09/2020, at 10:49 AM, Alec Smyth via Personal_Submersibles <personal_submersibles at psubs.org> wrote:
>> 
>> Hi Alan,
>> 
>> I don't think there are any microswitches in these. Nor in fact any sealed components at all that I saw.
>> 
>> Best,
>> Alec
>> 
>>> On Tue, Sep 22, 2020 at 5:24 PM Alan via Personal_Submersibles <personal_submersibles at psubs.org> wrote:
>>> Alec & Hank,
>>> when I was compensating linear actuators ( a long time ago ) mine had
>>> micro switches in them that stopped the travel.
>>> I am not sure whether the Lenco has them or not!
>>> I was sticking a hot needle through the plastic housing of the micro switch to
>>> help compensate them, as it was pretty well sealed & I feared it would randomly
>>> be switched because of the oil compensation pressure at depth.
>>> Also the brushed motors were sealed. This again may be a problem if the 
>>> compensating oil hasn't fully filled the cavities inside the motor housing &
>>> suddenly experiences pressure as you descend. The small brushed motors
>>> can have what Phil describes as a "herky jerky" action when oil compensated
>>> due to the oil lifting the brushes off as they spin fast.
>>> Mentioning this in case you encounter problems operating them at depth!
>>> Alan
>>> 
>>>> On 4/09/2020, at 9:59 AM, Alec Smyth via Personal_Submersibles <personal_submersibles at psubs.org> wrote:
>>>> 
>>>> Hi friends,
>>>> 
>>>> The PSUBS Community Projects page (http://www.psubs.org/community/projects/ ) now features an "open source manipulator" developed by Hank Pronk and me. This is an intentionally simple manipulator built using only a drill press and an angle grinder, except for a few plastic bushings that were turned on a lathe for expedience. We purposely avoided things like aluminum welding, to keep it's fabrication as accessible as possible. The page contains blueprints, photos, and a bill of materials - but I recommend beginning at the "Start Here" document in the ZIP file. Please don't hesitate to reach out if you have any questions, or if you have any suggested improvements.
>>>> 
>>>> Best,
>>>> Alec
>>>> _______________________________________________
>>>> Personal_Submersibles mailing list
>>>> Personal_Submersibles at psubs.org
>>>> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>>> _______________________________________________
>>> Personal_Submersibles mailing list
>>> Personal_Submersibles at psubs.org
>>> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>> _______________________________________________
>> Personal_Submersibles mailing list
>> Personal_Submersibles at psubs.org
>> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.whoweb.com/pipermail/personal_submersibles/attachments/20200923/5229a30b/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image1.JPG
Type: image/jpeg
Size: 198956 bytes
Desc: not available
URL: <http://www.whoweb.com/pipermail/personal_submersibles/attachments/20200923/5229a30b/attachment-0001.jpe>