Capillary Depth Gauge - necessity or anachronism

[ValeryUA]

Aa few words about myself.
Old diver - studied at the military school of divers of the engineering troops of the USSR
As our instructor said: "Divers are old and brave"
Also:
I am Mr. Valeriy Kulaha - individual inventor from Ukraine and former military diver of Soviet Army. I have obtained a US patent for the new construction of a capillary depth gauge. Patent US: 11525658
Combined capillary depth gauge
Receipt date:12-13-2022
The technical solution allows solving the main problem of capillary depth gauges — the nonlinearity of the scale. The design of the depth gauge makes it possible to obtain an almost linear scale at depths of up to more 100 m, as in modern membrane depth gauges. Also this is only one type of absolute instruments and can use like reference for other type of moderne depth gauges.
The corps depth gauge consists of three or four plastic parts connected by gluing together and a strap for fastening on the arm. According to preliminary calculations allows you to sell it in the range of $15 to $30
In the far away 1989, a small cooperative under my leadership produced and sold a depth gauge in the territory of the former USSR at the price of two packets of expensive cigarettes.
The device was similar to the known capillary depth gauge, but the technology of casting parts from plastic and subsequent gluing was used.

New device can be next scale from many version

I want to ask the community - Could this be helpful?

 

[vrokhlenko]

My father made one like that (simple one - out of a pen refill) probably 45 years ago - I still have it. i recently designed my own - to achieve "almost" linearity I gave it two coils - one is hidden inside and another is exposed. Problems are: poor visibility, especially at depth and clearing meniscus after taking it out of the water.

 

[ValeryUA]

My father made one like that (simple one - out of a pen refill) probably 45 years ago - I still have it. i recently designed my own - to achieve "almost" linearity I gave it two coils - one is hidden inside and another is exposed. Problems are: poor visibility, especially at depth and clearing meniscus after taking it out of the water.

I also use several capillaries - each for its own range. Maybe we even came to a close solution.
The cloudy meniscus most likely depends on the porosity of the material.
In computers, reading is better, but the capillary is rather designed to verify the correctness of the indicated depths - this is an absolute class of devices

 

[vrokhlenko]

There is only one solution - volume is inversely dependent on pressure

 

[ValeryUA]

Such a solution is applied in Swiss watches, it seems. The photo shows a noticeable narrowing of the channel at the end of the capillary.
By the way, if the capillary is made of glass, then the meniscus is perfectly visible and the glass does not become cloudy.

 

[vrokhlenko]

Such a solution is applied in Swiss watches, it seems. The photo shows a noticeable narrowing of the channel at the end of the capillary.
By the way, if the capillary is made of glass, then the meniscus is perfectly visible and the glass does not become cloudy.

Well, narrowing of the capillary and glass is out of my realm But interesting!

 

[Bill McIntyre]

Used one in the early 1950s but I can't see why I would use one now. The freedive computer I wear gives me depth along with lots of other valuable information.

 

[ValeryUA]

Used one in the early 1950s but I can't see why I would use one now. The freedive computer I wear gives me depth along with lots of other valuable information.

I have just one question: "How do you know what your computer is showing correctly?"
Although, even a faulty computer is useful for diving in the pool.

 

[Bill McIntyre]

I have just one question: "How do you know what your computer is showing correctly?"
Although, even a faulty computer is useful for diving in the pool.

How do you know your capillary gauge is showing correctly? I suspect that my computer is more accurate than the gauge. The depth sounder in my boat tells me the depth, and the computer seems to match it pretty well. I just realized that this thread is in a scuba forum and I'm a freediver, so maybe I'm in the wrong place. But my computer shows me dive time and most important, surface interval. Your capillary gauge doesn't do that. And of course scuba divers use gauges that show even more.

 

[Hyscore]

My first depth gauge in the 1960s was an SOS capillary gauge. I still have one that I picked up on eBay and use it when I am training snorkellers. So far as I am aware no one is manufacturing new capillary or mechanical depth gauges nowadays. Everything has a battery and more functions than a snorkeller needs. If you manage to get your gauge to market I think it would be of interest to people like me who just want to know their depth on relatively shallow breathhold dives. The expanded shallow scale on a capillary gauge is ideal for this. As for using it to check computers, I think not. I always scuba dive with two computers and that is a reasonable enough check for me.

 

[Periwinkle]

My first depth gauge in the 1960s was an SOS capillary gauge. I still have one that I picked up on eBay and use it when I am training snorkellers. So far as I am aware no one is manufacturing new capillary or mechanical depth gauges nowadays. Everything has a battery and more functions than a snorkeller needs. If you manage to get your gauge to market I think it would be of interest to people like me who just want to know their depth on relatively shallow breathhold dives. The expanded shallow scale on a capillary gauge is ideal for this. As for using it to check computers, I think not. I always scuba dive with two computers and that is a reasonable enough check for me.

I agree 100%. As a freediver I would buy one. I used to use one in tandem with the SCUBA and found it better resolution for depth when doing a decompression stop. Then we started planning not to do decos and it seemed redundant. (1980s obviously)
For freediving it was great, I had it on when I dived to over 16m years ago, didn't realise till then how deep I was getting. Glad I'm still alive and aware now, the eighties are scary to look back at.....

 

[ValeryUA]

Моим первым глубиномером в 1960-х годах был капиллярный манометр SOS. У меня все еще есть один, который я купил на eBay и использую, когда тренирую сноркелинга. Насколько я знаю, в настоящее время никто не производит новые капиллярные или механические глубиномеры. Все имеет батарею и больше функций, чем нужно сноркеллеру. Если вам удастся вывесить свой датчик на рынок, я думаю, что это будет интересно таким людям, как я, которые просто хотят знать свою глубину на относительно неглубоких погружениях с задержкой дыхания. Расширенный мелкий масштаб на капиллярном калибре идеально подходит для этого. Что касается использования его для проверки компьютеров, я думаю, что нет. Я всегда ныряю с аквалангом с двумя компьютерами, и это достаточно разумная проверка для меня.

Almost ready to sell! Latest technology improvements and tests. I think the price will not be more than 25 dollars. This option is for freediving, snorkeling and a reserve parachute.

 

[ValeryUA]

How do you know your capillary gauge is showing correctly? I suspect that my computer is more accurate than the gauge. The depth sounder in my boat tells me the depth, and the computer seems to match it pretty well. I just realized that this thread is in a scuba forum and I'm a freediver, so maybe I'm in the wrong place. But my computer shows me dive time and most important, surface interval. Your capillary gauge doesn't do that. And of course scuba divers use gauges that show even more.

The capillary depth gauge does not have any parts other than the housing. The body and length of the capillary are calculated according to the Boyle-Mariotte law and it cannot change throughout the life of the device. This is a direct indicating device and it either works or not