[PSUBS-MAILIST] K-350 blue print problems

Thu Sep 5 20:27:37 EDT 2013

So first failed test. I filled my oil compensating bladder and used marvel mystery oil. It ate away at the rubber of the bladder. I am useing rubber for landscapping pond liners. I think marvel mystery oil is a solvent. Should I use mineral oil or something?
Thanks,
Scott Waters

Sent from my U.S. Cellular© Smartphone"Dan H." <jumachine at comcast.net> wrote:Scott

In your lathe,, turn and face a piece of stock about 1/2 inch long and a little under the small diameter of your lens. (a flat disk) Flip it around and drill a center hole in it with a center drill as you would in the end of a long shaft you want to turn in the lathe.  (A hole to accept the lathe center)  Don't go all the way through. Take it out and cover the faced end with strips of double sided tape.

Mount another chunk of round stock, just a little smaller in diameter then the larger diameter of the viewport in the chuck of your lathe.  Face it true and cover it's face with double sided tape also. 

Center up and stick on your lens blank then take the smaller piece you already prepared, hold it up against the tail stock center and crank it up against the other side of the lens blank. 

With the lens taped to the drive plate and held in place with the force of the tail stock, you should be able to machine the taper you need.  Of course, take light cuts and keep a close eye on it. 

Dan H.
----- Original Message -----
From: swaters at waters-ks.com
To: personal_submersibles at psubs.org
Sent: Thursday, September 05, 2013 9:57 AM
Subject: Re: [PSUBS-MAILIST] K-350 blue print problems

Vance,
I am in the process of installing veiwports. How do you chuck up the conical viewport in the lathe to make a mating surface for the "O" ring? Can't seem to figure out how to make it work on the lathe and have access to the edge that I need to cut.
Thanks,
Scott Waters 

-------- Original Message --------
Subject: Re: [PSUBS-MAILIST] K-350 blue print problems
From: vbra676539 at aol.com
Date: Wed, June 12, 2013 4:01 pm
To: personal_submersibles at psubs.org

I haven't tried the Nekton style on my K-frames, but will. Gamma uses a cork/neoprene blended gasket material, glued to the frame with aircraft grade gasket cement, but dry on assembly between the gasket and acrylic. If the compression is sufficient on the      K-style, it should work there, as well.

I'm not a big fan of gaskets or flat disc viewports in any case, but 12,000+ dives for the Nektons is a pretty good statement. They work. Do not use straight neoprene gaskets, and I suspect that unglued urethane gaskets fall into the same category. They are too soft and will extrude to the low pressure side.

Side note: I HATE using silicone sealant in this kind of application. It works fine, but makes maintenance impossible. If you're going to do it, then just go ahead and build some extra viewports. You'll need them for replacements the next time you paint.

To complete Dan's (hey, Dan, good to hear from you again) conical viewport--machine a matching notch in the viewport frame, and as Dan describes, take off the corner of the port  so that your o-ring sits in a square (in cross section) groove. Compression from your retaining ring will complete the form and it will not leak (ever). No sealant or glue is required for this design.

A well painted frame greased with oxygen compatible grease is what you want. The o-ring serves to keep the deep blue sea out on or near the surface, but the acrylic self-seals against the mating surface under pressure.

As to building the frustrum conical seats, Dan is also right. You can't get there from here without machining after welding. Perry build their conning towers as bolt on units, and that was the primary reason. A conning tower can be handled on regular floor sized machine tools. An entire submarine normally can not.

If I was building another K, it would have some very-Perryesque modifications--a bolt on conning tower with six ports in the cylinder being one of them.

Vance

-----Original Message-----
From: Dan H. <jumachine at comcast.net>
To: personal_submersibles <personal_submersibles at psubs.org>
Sent: Wed, Jun 12, 2013 5:56 pm
Subject: Re: [PSUBS-MAILIST] K-350 blue print problems

I'd prefer to have all conical viewports and I don't think you can properly gasket a conical viewport.  A rubber O-ring that seals at the edge where the lens meets the seat is as good as it gets on a conical viewport.  The shape of the cone and the pressure on the big side of the cone ensure you'll never have a gap to extrude the O-ring.  If it wasn't so difficult to machine the viewport seats conical after they are welded, I would have used all conical lenses and O-ring seals.  It's impossible to hold the seat true if you machine a cone first then weld.

Gaskets on the flat viewports may be good too.  If it works for Vance then it should work for you.

Dan H.
----- Original Message -----
From: hank pronk
To: personal_submersibles at psubs.org
Sent: Wednesday, June 12, 2013 5:22 PM
Subject: Re: [PSUBS-MAILIST] K-350 blue print problems

Dan,
are you against gaskets like Vance has on the Necton.
Hank
From: Dan H. <jumachine at comcast.net>
To: personal_submersibles at psubs.org 
Sent: Wednesday, June 12, 2013 3:04:27 PM
Subject: Re: [PSUBS-MAILIST] K-350 blue print problems

I used sealant in the rest of the viewports. 

I was concerned that the coefficient of expansion would be to great on the 15 inch viewport so that in really cold water there may be to big of a gap and possibly extrude the O-ring in along side the lens.  I know it could be a problem with the sealant also but I simply went with seemed to work for others on the all the rest of my viewports....   Glue them in with sealant!!!

Dan H.
----- Original Message -----
From: swaters
To: personal_submersibles at psubs.org
Sent: Wednesday, June 12, 2013 4:42 PM
Subject: Re: [PSUBS-MAILIST] K-350 blue print problems

Dan,
 Did you put o-rings around all your view ports or did you seal the 8 inch veiw ports with sealant?
Thanks,
Scott Waters

Sent from my U.S. Cellular© Smartphone

"Dan H." <jumachine at comcast.net> wrote:
I don't know.  There isn't a lot of room for sealant in a conical viewport.  

I like the fact that if I were to be incapacitated in the sub, all someone would have to do to get access to me is remove the six screws on the lens holder and easily pop the lens out to get access to the interior of the sub when it's not glued in. 

My hatch latches from inside only, as the K-350 plans show.

Dan H.
----- Original Message -----
From: swaters
To: personal_submersibles at psubs.org
Sent: Wednesday, June 12, 2013 2:22 PM
Subject: Re: [PSUBS-MAILIST] K-350 blue print problems

What about 3M marine poly sealant #4000? Would that work?
Thanks,
Scott Waters

"Dan H." <jumachine at comcast.net> wrote:
Machine the sharp edge off the top side of the viewport lens so it creates a triangular cross section groove when installed in the conical seat and install an O-ring before bolting down the lens retaining ring. 

Do a 10 or 20 time size drawing of the            cross section groove area with any standard cross section O-ring of your choice.  Draw in the lens edge to create a situation where you have about .020 inch squeeze on all three sides of the triangular gland.  (seat, lens retainer and lens edge when the sharp part is machined off)  That's how to determine how much to machine the lens edge.  Get the squeeze to .020 inch per side on the O-ring.  Try fan O-ring of .250 cross section or maybe a little less and see what you think.  When you get the O-ring cross section and groove pinned down, pick an O-ring of a diameter that will fit.  No sealant necessary.

Also you should grease the O-ring and            conical seat before instillation.

Dan H.
----- Original Message -----
From: Jon Wallace
To: personal_submersibles at psubs.org
Sent: Tuesday, June 11, 2013 11:24 PM
Subject: Re: [PSUBS-MAILIST] K-350 blue print problems

It was sikaflex all the way around on the 600.  The problem with it is that you really have to bang on the viewports to get them out and at least the way I removed them, I would only put back new ones.

On 6/11/2013 11:16 PM, swaters wrote:
Why did Kitteregde use a gasket and a "O" ring on the big veiwport and not on the small veiwports. Hank, why did useing the silicone suck? Was it hard to apply or did it not hold up well?
Thanks,
Scott Waters

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