Snorkel options?

[Timothy L]

I have not seen any feedback on Bob Martin’s snorkel - which, so far, will be used in my 1/72 Virginia class (with R&R wtc) shown below.

I have attached one of David M’s photos which I “think” includes s snorkel valve (or is it a device for lowering masts?). If a snorkel, are there drawings available or can one be purchased?

I would like to know what folks recommend for snorkels and if you have experience with Bob’s snorkel. Thank you.

[He Who Shall Not Be Named]

I have not seen any feedback on Bob Martin’s snorkel - which, so far, will be used in my 1/72 Virginia class (with R&R wtc) shown below.

I have attached one of David M’s photos which I “think” includes s snorkel valve (or is it a device for lowering masts?). If a snorkel, are there drawings available or can one be purchased?

I would like to know what folks recommend for snorkels and if you have experience with Bob’s snorkel. Thank you.

Here are some shots of various type snorkels we developed over the years -- each one suits a specific sail internal geometry.

Give me the height, width and length dimensions (Imperial, Damnit!) of the cavity within your sail and I'll fix you up.

[Timothy L]

David - thank you (I would elaborate on my gratitude - but I’m pretty sure you get it by now!!!). But I WILL throw in a “holy crap - you bet I will send dimensions - thank you so much David!!!”

Bob Martin describes his snorkel specifically for the R&R wtc line in this manner:

“This was designed specifically for use with systems such as the R&R WTC, which I represent. As such, the actual seal interface is specifically designed to offer a slight leak. This is vital, as without this feature, the valve would not open if you are running your pump and the snorkel breached the surface, as the air vacuum would keep the ball sucked against the body. With a small leak, the pump can still pull a vacuum and blow ballast for full static diving, but the valve will open as soon as it breaches the surface.“

Does his functional description (“designed to have a slight leak” apply to all “snorkel” valves regardless of the type of WTC used? This question may sound woefully ignorant but it’s a “sometimes you don’t know what you don’t know“ type of question.

David, I will send dimensions in an email today.

[He Who Shall Not Be Named]

David - thank you (I would elaborate on my gratitude - but I’m pretty sure you get it by now!!!). But I WILL throw in a “holy crap - you bet I will send dimensions - thank you so much David!!!”

Bob Martin describes his snorkel specifically for the R&R wtc line in this manner:

“This was designed specifically for use with systems such as the R&R WTC, which I represent. As such, the actual seal interface is specifically designed to offer a slight leak. This is vital, as without this feature, the valve would not open if you are running your pump and the snorkel breached the surface, as the air vacuum would keep the ball sucked against the body. With a small leak, the pump can still pull a vacuum and blow ballast for full static diving, but the valve will open as soon as it breaches the surface.“

Does his functional description (“designed to have a slight leak” apply to all “snorkel” valves regardless of the type of WTC used? This question may sound woefully ignorant but it’s a “sometimes you don’t know what you don’t know“ type of question.

David, I will send dimensions in an email today.

For any given differential-pressure between the valve seat and the valve element (be that element a section of sphere or a flat rubber disc), the force is directly proportionate to the area of the seal effected by the mechanism; the larger the sealing area, the greater the force keeping the seal up against the seat.

The R&R seal area is large, thus even a relatively low differential-pressure will keep the light-weight ball sucked up onto the seat. An inherent 'leak' will, over time, drop the differential till the retaining force drops below the gravitational pull of the element (the ball). On OK situation if a small amount of water intrusion is acceptable to the system.

The seal area of the D&E Miniatures snorkels is extremely small, so that even at a very high differential-pressure the rubber element will disengage from the seal once the buoyant element (a hunk of foam), to which it is attached, rises above water level.

Our snorkel is gas-tight when closed. When working properly (and God knows, that's not always the case, hence the back-up safety-float valve which affords two-valve protection... 'real' submarine design criteria) there is no water intrusion into the system.

[Timothy L]

Thank you David. After reading your response I realize I’m woefully ignorant of how any of these ballast systems work - not something I’m proud to admit. Questions that come to mind (ex. does the R&R need one of your backup valves etc etc) are akin to a blindfolded man flailing in a dark room to find the exit.
I have looked at your Master Class discussion on the Secret Projects site, looked at explanations on Bob’s ND site, read his book, and still don’t have a clue. I don’t lack intelligence - but something is missing.
Almost always I learn by doing (not so much by reading or listening). I haven’t touched the R&R cylinder yet because I’ve been chipping away at the hull. So I think at this point it is better to wait until I can throw the WTC into a test tank and just study what happens - ie learn how it works by playing with it. Otherwise I realize my lack of understanding is wasting your time. I’ll have to “resurface” when I get to that point.
In the meantime, I am ignorantly wondering if I should have your blowback safety valve installed in my R&R - or does that question just flash my ignorance up in neon lights??? I shall persevere!

[redboat219]

Tim, the back up float valve prevent any water that may have gotten past the snorkel induction pipe float valve from inudating the dry space in the wtc.

No real application in the R&R cylinder as the float valve has no connection to the dry space.

[Timothy L]

Redboat219 - Thank you. I guess the neon lights were flashing lol!

[He Who Shall Not Be Named]

Thank you David. After reading your response I realize I’m woefully ignorant of how any of these ballast systems work - not something I’m proud to admit. Questions that come to mind (ex. does the R&R need one of your backup valves etc etc) are akin to a blindfolded man flailing in a dark room to find the exit.
I have looked at your Master Class discussion on the Secret Projects site, looked at explanations on Bob’s ND site, read his book, and still don’t have a clue. I don’t lack intelligence - but something is missing.
Almost always I learn by doing (not so much by reading or listening). I haven’t touched the R&R cylinder yet because I’ve been chipping away at the hull. So I think at this point it is better to wait until I can throw the WTC into a test tank and just study what happens - ie learn how it works by playing with it. Otherwise I realize my lack of understanding is wasting your time. I’ll have to “resurface” when I get to that point.
In the meantime, I am ignorantly wondering if I should have your blowback safety valve installed in my R&R - or does that question just flash my ignorance up in neon lights??? I shall persevere!

Tim,

Romel summed it up better than I.

So, Use Bob's snorkel if you're using Ron's WTC. Use mine (still awaiting your e-mail with mailing address) if you're going with a SubDriver.

[Timothy L]

“So, Use Bob's snorkel if you're using Ron's WTC. Use mine (still awaiting your e-mail with mailing address) if you're going with a SubDriver.“

Got it. Thanks David. Will use Bob’s snorkel. Ignore email sent yesterday. Will resurface after “hands on” homework