[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [PSUBS-MAILIST] Viewport Question.



Alex,

All you need to check flatness of the viewport seats is something flat that's the diameter of the lens and a set of feeler gauges. The first thing that comes to mind for a flat reference is a disk of steel or aluminum faced flat on a lathe. If not that maybe even a piece of plate glass cut and nipped to fit into the housing.

With the flat piece in the housing you can try to fit the feeler gauge shims in behind it from the inside. If you can't fit any shims in, it's flat. If you find you have a wobble you can stack up shims to see how much out of flat it is.

Your out of roundness is most likely an oval with one wide spot and one narrow spot. It's probably going to be wide from top to bottom and narrow from side to side because of the geometry of the intersection of the two parts. If you don't have an inside micrometer set you can measure it with a piece of rod, say about a 1/4 inch diameter, cut to just fit the diameter of the hole in the narrowest part and then use it and a feeler gauge to measure how loose it fits when inserted in the same hole but in the widest part.

Either that or wander up north on Rt 81 and I'll loan you the gauges.

If you have to, a larger shop could put the whole conning tower on a boring mill and true it up for you but hold on to your wallet.
Dan H.
----- Original Message ----- From: "Smyth, Alec" <Alec.Smyth@compuware.com>
To: <personal_submersibles@psubs.org>
Sent: Tuesday, December 11, 2007 1:17 PM
Subject: RE: [PSUBS-MAILIST] Viewport Question.


Hi Dan,

I noted your comment about the slight distortion of the viewport seats
after welding. I've made mine rather massive in an effort to avoid that,
but d'you have a tip regarding how I can check whether it worked? I'd
love to get a dial indicator on them, but don't see an obvious way to do
that since they're welded into the coning tower. I'd really like to
check whether they're still flat before the tower goes on the sub, since
it should be possible (though admittedly hard), to refinish them by
turning the whole coning tower on a lathe.


Thanks,

Alec


The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it.

From: owner-personal_submersibles@psubs.org
[mailto:owner-personal_submersibles@psubs.org] On Behalf Of Dan. H.
Sent: Tuesday, December 11, 2007 8:31 AM
To: personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST] Viewport Question.

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



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






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