Re: [PSUBS-MAILIST] Blueglobe cable glands

[Jon Wallace <jonw@psubs.org>]

It looks like these units are simple compression fittings.  You can make 
your own by using a brass compression water plumbing fitting for sinks 
and toilets.  For example, on my underwater camera I used 1/8npt x 5/16 
compression, removed the brass compression sleeve, and substituted it 
with a grommet that fit tightly both around the wire (USB) and inside 
the compression fitting wall.  I added a nylon washer on both sides of 
the grommet to both take up space and provide a surface to compress the 
grommet.  I never tested mine however to determine exactly what the 
pressure rating would be and so never considered it for the pressure 
hull.  If the fitting failed and I lost the web-cam then I only lost 
$79, but didn't want to risk an issue with the pressure hull.

It's nice to have some test numbers that give some idea of the pressure 
rating, however I suspect that the rating is going to depend not only on 
the wire jacket but also on the amount of torque applied to the nut to 
compress the rubber grommet.  Too little torque will reduce the pressure 
rating.  Too much torque could extrude the compression material, crack 
it, rip it, or fail by some other means by putting too much force on the 
material.

Jon




************************************************************************
************************************************************************
************************************************************************
The personal submersibles mailing list complies with the US Federal
CAN-SPAM Act of 2003.  Your email address appears in our database
because either you, or someone you know, requested you receive messages
from our organization.

If you want to be removed from this mailing list simply click on the
link below or send a blank email message to:
	removeme-personal_submersibles@psubs.org

Removal of your email address from this mailing list occurs by an
automated process and should be complete within five minutes of
our server receiving your request.

PSUBS.ORG
PO Box 53
Weare, NH  03281
603-529-1100
************************************************************************
************************************************************************
************************************************************************