Re: [PSUBS-MAILIST] Viewport Question.

[" Dan. H." <jumachine@comcast.net>]

James,

Also be aware that acrylic thickness isn't constant even when cut from the 
same sheet.  It may be wise to have your acrylic parts in hand before 
machining your rings.

The only way to get a truly good fit between the lenses and housing rings is 
to do a final machining after the rings are welded into the hull, but most 
of us don't have that option.  Anything else is just doing the bet you can 
do with what happens after welding and the tolerance of the acrylic you get.

Hey!  Nice web site!
Dan H.
----- Original Message ----- 
From: "James Frankland" <james@guernseysubmarine.com>
To: <personal_submersibles@psubs.org>
Sent: Tuesday, December 11, 2007 6:02 AM
Subject: [PSUBS-MAILIST] Viewport Question.


Hello All.

Quick question regarding viewports tolerance.

Ive started machining and have done 2 at the moment.  Ive machined the depth 
of the bore to be exactly 1.25 inches as per the plans, and the inside 
diameter i have machined to 8 inches plus a clearance of 0.5 mm to allow the 
lense to drop in.  (sorry, the plans are imperial but we're metric here, so 
its a bit of both).

Im not making the acrylic lenses myself, i will buy them (probably from 
psubs store).  Assuming they come in exactly at 8 inches OD, as things are 
they should slot in nice and tight.

But Dan H mentioned to me that he got some slight distortion on the ports 
after welding.

So the question is, do you think 0.5 mm clearance is enough?  Obviously i 
cannot alter the ports once they are welded in, and don't want to have to 
start machining the lenses, they must fit.

You can have a look here as usual.  Some of the text titles are wrong.  I'll 
change them later.

http://www.guernseysubmarine.com/index_files/Page7497.htm

Any thoughts?

Thanks
James




----- Original Message -----
From: Jay K. Jeffries [mailto:bottomgun@mindspring.com]
To: personal_submersibles@psubs.org
Sent: Mon, 10 Dec 2007 20:16:42 -0500
Subject: [PSUBS-MAILIST] Digital Multi-Frequency Scanning Sonar

Here is what looks like a great scanning sonar for a PSUB.  If it is priced
like some of their other products, it should be a great deal.



http://www.imagenex.com/html/881l_imaging.html



R/Jay





Respectfully,

Jay K. Jeffries

Andros Is., Bahamas



A skimmer afloat is but a submarine, so poorly built it will not plunge.








************************************************************************
************************************************************************
************************************************************************
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
************************************************************************
************************************************************************
************************************************************************