What a great video! As a beginner these videos have been extremely useful in making me understand the equipment, and making me a better diver in the process. Thank you for sharing!!!
As a “big” guy who has been diving for ever, this was very informational and helps make sense. Plus after watching your video on your training (I took my course in 1974!) I’ve decided to go back this Spring and take a refresher. Even though I’ve been rec diving for years, taking time off and coming back, it really made me think and decide, why not take a course and make sure I’m “up to date” with my training. Thanks for these great videos Alec!
I smart decision Paul. May of us stone age divers have lots of dives but the new gear and training keeps you current, safe and enjoying diving longer. Stay safe my friend.
Thanks ALEC for your explanation.I am 54 years and kind of the guy you just described even with the same regulator!!!! It is a very good help for all divers.Keep following yor tech tips
I can't remember how many of your videos I've seen so far and I learned a lot from you some things I didn't know, I've been certified since 1989, and I learned your never to old to pickup something new. Thank you for sharing your passion I also have for diving. 🇺🇲👌🏼
I am so glad I watched this video and your excellent explanation about the venturi switch. I thought there was something wrong with my regulator. Now all I have to do is adjust the lever when my regulator starts blowing air and everyone is looking at me. LOL!!!!! Thank you very much.😊
Great explanation again! Every time I watch your videos, even on a subject I thought I knew, you show me something I never knew before. I love your presentation style too, simple and to the point without any flashy green screens or animations, just a man in his workshop showing us the ins and outs with practical demonstrations. Thanks for your uploads, haven't found a single bad one yet! -Rob
Hi Alec, I just bought a new reg, a Scubapro MK11/C350. I just wanna say thank you, because I happen to watch this video just before my first dive with my new reg and could really understand about the venturi feature - and not panic when it easily freeflowed because I already know what made that happen - because of this video! Keep these useful videos coming!
Comments like yours are what make the work worthwhile. If I can help just one diver understand his gear better and maybe enjoy his dive more, I'm happy. Thanks very much. Alec
I love your channel. I'm getting back into diving after 23 years, since I was a teenager, and your channel has brought me up to date. Thx you and keep em coming....
great explanation and most importantly, demonstration of the venturi effect in a 2nd stage. I came to this video trying to understand what a venturi caused free flow is and I learned so much more than that, including how a 2nd stage works. TNX !!!!
You, sir, are a mentor to a student like me. Thank you and Kevin for the time spent making these videos. Your contributions to all things diving are immeasurable.
this has been the single most informative video I have ever seen, just watched it with my 12yr old boy who is doing his open water along with me, he now understands how the regulator works, what the parts are, and what a venturi does, brilliant video
You have a great talent for explaining things in a simple and understandable way. I'm very fit but you never know what condition you could run into under water that might exhaust you (like being chased by the Loch Ness Monster ..lol ) and having that venturi can save your life. Worth the extra bucks.
Hello Alec! Thank you so much for all your super informative videos. But this is one of my favorites! Wow, no one explains this as well as you do. This was a spectacular demonstration of the Venturi effect, which is basically the Bernounilli's principles of pressure differential in moving air ( the principle responsible for modern aviation). The rapid flow of air inside the diaphragm causing the pressure to drop significantly as compared to the pressure outside the diaphragm, and thus the diaphragm will continue to be "pushed" in as long as the flow is there. This principle applies to air flow within a narrow tube is called the Venturi effect allowing continuous air flow and thus helping the diver putting forth less effort on air-sucking. The manufactures called this Venturi-assisted, indirectly implying somehow they created this technology, but it is nothing more than the natural physics principle discovered by Giovanni Venturi in the 18th century. Closing the lever will partially close down the tube and slowing rate of air flow to the point the pressure in the chamber will rise enough together with the return force of the diaphragm back to its normally closed position, thus abolishing the Venturi effect. So the question is do we actually need this lever in the alternate second stage, commonly used only in an emergency? Probably not. Do we need the lever to prevent accidental free flow in the primary second stage when the purge button is struck, or when we need the Venturi effect to get more air with less effort? Probably. Your choice. It appears that the manufactures often charge hundred of dollars more to have this lever put in to their newest models, everything else being equal. Finally Alec, I am new to diving but watching your videos helped me learn a lot about this wonderful sports and save a ton of money at the same time, buy not purchasing unnecessary equipments!
Clearly your understanding of Bernoulli's Principle is solid and you're right. It's nothing new. Re the design of regs, I agree that the venturi is NOT necessary in a safe second. In fact, it may cause more problems than any advantage offered. I don't mind it in the primary provided it can be adjusted to minimal effect if wanted. When the diver needs some assist, he just dials it in. DACOR (and maybe others) had a neat venturi system in which the lever had a vane on one side that directed the air across the diaphragm but only when the lever was depressed a lot. That is, with a normal shallow breath, there was no venturi effect but if you drew a big breath, as when you needed more air, the vane on the lever was drawn into the air stream and directed the air across the diaphragm to create a venturi effect. Essentially you automatically got a venturi asist when your needed it - automatically. Glad you've been enjoying the vids. Take care. Alec
Great Video as usual. What you did not say in direct words (as you were talking to novices) was 'ease of breathing' although you certainly discussed it. In one article a tech diver said was that you can literally just take 3 breaths a minute (at rest) underwater. He was right. (7 second inhale, 7 second hold, 7 second exhale). I cannot do that on land! I attribute that to the light weightiness feeling in water and the EASE of breathing from the Venturi regulator. I have show students the difference in feel too, as you were showing on video with good, well maintained regulators vs some of the horrible ones I have seen used for pool use (and as rentals!). I do consciously try to do slow deep relaxed breaths while diving. As a result I have great deal more air than most of the group coming back. A venturi certainly helps. Full disclosure- I am a big guy and usually dive sidemount or with other gear/cameras- so more drag than most.
My test subject is always Kevin. He is a tiny diver just like a blue whale. He loves the venturi effect for his big lungs and slow breathing can make air last a long time.
Thanks for another great episode. I know you have mentioned doing an episode or two on drysuits. Just wondering how that might be coming along. Thinking of taking that plunge soon and would love to hear your thoughts.
Wow Alec, great presentation. Very illustrative, mostly for somebody that is restarting to dive after more than 30 years of not doing it and needs to know how the equipment works nowadays. Keep on with the good work.
Most things haven't changed - new materials and some new technology. But we still fin up and down - not sideways (except for the odd tech diver) and have the same old problems -fogging masks, dives are too short, etc. Have fun. Alec
Alec again thank you. A few years ago I bought a new reg set actually a ScubaPro set and spent a bit more than $800.00 on them. They have the venturi feature and until now I didn’t really understand the function. The only thing I knew is that the lever had to be off and then pushed forward when I was ready to start my descent. I thought that spending the extra money on the regs that the first and second stage where just better quality but now I understand that maybe I didn’t have to spend that kind of money to get a good reg set. Well too late for that now. I am totally satisfied with them and hopefully they will last me years to come. Keep up the great work with these videos as I am learning so much from them and I am becoming a well informed diver because of them. Hats off to you Alec and your no nonsense approach to things.
I'm glad I was able to enlighten you a bit Martial. Don't be concerned about the few extra bucks to get a Venturi. It probably wasn't much and eventually, you may find it was a good investment. You have Scubapro regs so you'll have them for a long time. The day may come, with age or a perhaps certain dive situation, where you will be glad you have it. Take care.
Love your content. I really appreciate the Venturi effect when diving in the 60m (180 ft) + range. As gas density increases with depth this has an effect on the WOB. The Venturi really helps with breathing dense gas mixtures.
I have found these videos so interesting. You go in great detail with all the gear and throw in some personal experiences while explaining which are very memorable and I can easily relate your suggestions to my own gear. Thank you so much for doing this and sharing you broad knowledge on diving!
Well thank for watching. I'm glad you're enjoying it. I enjoy making the videos or it that too obvious? Almost every day someone asks why I don't make money on U-Tube. My answer is simply - my viewers don't want ads and I don't want to spoil my fun. Take care. Alec
Thank you Sir....for another information packed video. Your delivery of the material and attention to details...make it a great way to learn. Please keep up the amazing work!
I’ve only just discovered you and your tech tips. You are a revelation! I love watching your videos, you explain things in a way anyone could understand and you clearly have a LOT of experience. You also make me laugh a lot. Keep up then good work, I’m telling all my dive buddies about you!
Excellent video Alec. One question, since you have shown us the way the assist functions, would you be willing to explain how/what is happening in the regulator when a diver uses the breathing adjustment knob as featured on your example regulator in this video? Best.
Alec, I have that reg. Mine on the venturi says surface or dive or something to that effect so I always thought it was just a free flow issue. It sounds like I am wrong from the video. Love the videos!
Some regs, Scubapro comes to mind, have a 'Pre-Dive and Dive' setting. Others might say 'Surface and Dive' or whatever. Strictly speaking these are not Venturi settings but simply devices that attempt to eliminate the sudden FreeFlow from a second stage it it's dropped into the water or if the purge is pressed on the surface. In the case of Scubapro, it's just a small lever that keeps the diaphragm from being pushed inwards too far. Other regs use different methods but the intent is the same - on Pre-Dive you have less chance of a FreeFlow; on Dive you have the least breathing effort. Just use it as suggested. Turn it to Dive after you enter the water. Alec
Well, thanks Matt. I have found (over 2 million views) that each video has something for someone. I'm glad you found something useful in this one. Alec
Alec What an amazing video!! I bought a scuba pro MK25EVO and A700 reg a year ago and it has a Venturi on it. I found this Venturi useful on a dive on el um farod wreck in Malta, we were swimming back into quite a strong current and this Venturi helped a lot when I turned it on. I wasn't sure of the science behind it, I just knew it helped me. Now I know why!! Me and my 19 year old boy love your videos and think you're well cool, keep up the good work!! Kind regards Johnny Battiste
Alex Great job on explaining how the Venturi does and how it helps out at diver. Keep the video's coming I miss not seeing one a week from you about fixing them. We live down in FL and started diving over five years ago in upstate NY. Diving in Lake George very cold around this time of the year. I'm glad we live in FL now on the west coast side. Can you tell what a PADI or if NAUI tec course on maintaining your equipment goes through and is it worth it? Thanks Will
Diana and I are looking at getting a home in west Florida - in Little Canada close to Kissimmee. The Equipment course is always a good idea. It mainly shows you how to take care of your gear so it lasts a long time. That alone is valuable besides the technical information you pick up about operation. Take care. Alec
You nailed the explanation of what i had diving this holiday against current. Had the Mares rover from dive center, but against the medium current it was a hard work for me and didnt give enough air for me.
I love love that vid Alec, really great and made me to understand even more the benefits and how to not have a free flow too easily ;) ... I have that exact reg 1st and 2nd stage except mine if the 50th edition bronze ...
Few dive shops can do a pressure test. The test chambers are very expensive - $2000+. There's no way divers will pay enough to warrant having one. And you cannot test the computer functions, only the watertightness and even that's iffy. If you've just installed a new battery and O-Ring and want to test it, the only way to know if it's watertight is to take it down in the test chamber while in water (easy to do) and then open it afterwards. If it's dry it's good; if it's wet it's ruined. And if it is dry, then you have to reseal it and repeat the above. See? It's not as definitive as you might think. The test chamber will check the depth and time readings. That's about it. Any other dive computer problems can only be addressed by the manufacturer. Alec
Great video my friend. Pushing forward with my training to become an instructor. Bye spring I hope. Suggest a video: Are LED lights better than the old bulb type. And service your light. Maybe a video on transporting your tanks.
LED vs incandecent bulb - not even close. MUCH brighter and uses so much less power so smaller overall package, or longer life) and they don't burn out/break filament. He did a video (very useful) on why you want to remove your batteries between dives for storage. I ruined one cheap light not doing it. I remove them after each wkd dive now.
Once again, you bring us a fantastic video. You truly are an awesome educator and presenter. Thanks! By they way, how is that video on painting or refinishing aluminum tanks coming along... (hint hint) lol. You are doing a great job!
Alec, I just got back from diving in Belize. Prior to my trip I had my regulator serviced (1 stage piston and the spring replaced, and the second stage had internals replace with the exception of the diaphragm). I have a scuba pro MK25 (1st Stage) with a MK x650 (2nd Stage). It has the lever for surface/dive modes with a knob for flow resistance. While on the surface there are no problems. However, whenever I dive (~5-15 feet) the regulator will have a higher resistance as I start to breath in and it then "pops" and flow resistance drops. The problem occurs most of the time. I have tried adjusting both the lever and knob in various positions to try and correct the issue, but it not always corrects the problem. Even when I think I have the problem fixed and leave both the lever and knob in a given position at the end of a dive (where the problem appears to be corrected) it returns on subsequent dives. I don't think there is an issue with the spring and piston on the first stage, but I could be wrong. Any ideas as to what might be going wrong? The meltdownman
It's hard to analyze a regulator without it being in front of me and on a test bench, even with your vivid description. I can say with some certainty that it is very likely the 2nd stage as you have already surmised. The 1st stage is a go/no go system. If it's working properly you get air. If it isn't, you don't. The poppet & seat of the 2nd must be installed just right or performance will be sketchy. I suggest you take it to your dealer. Under the circumstance he ought to take care of the problem promptly & at no charge. It is likely a small matter but it is his responsibility. Parts are cheap so it's just a bit of his time. Get back to me if the problem isn't rectified. Alec
@@AlecPeirceScuba_SeaHunter Thank you for your response. I am learning more about equipment and how my gear operates better than any other teachings that I have come across in my 30 years of diving. You are a credit to the industry. Thank you and your staff for all the work you have put into your videos. You are all professionals. Thank you again, The Meltdownman
Thanks, Alec, another great explanation. Your Tech Tips have saved me so much money, I was finally able to buy that ScubaPro G2. ;-) Well maybe not enough for the G2, but you have definitely decreased my annual expenditures significantly and increased the life and reliability of my gear. I really did get the G2 and love it, although I look a little odd diving with a G2 and twin steel 70s with a J-valve. Still looking for a twin hose regulator.
Hi Alec, Love your videos. I recently got recertified and have been watching you tech tips on what a person really needs. My son and daughter wanted to get me a regulator first and second stage for Christmas which they did. MK 25 Evo with a A700 reg. I told them it was way to much and over the top, but they insisted. I now need a safe second and would really value your thoughts on what to get. I am from the PNW and cold water dive, but will travel to Florida and Hawaii in the future. Thanks again.Scuba Pete
You can get a good octo from Scubapro if you like but I'm a fan of the specific safe second designs. Oceanic has one and Sherwood too. They are a lot less expensive, work as well if not better and are much easier to deploy in an emergency. Check out the AltAir from XS Scuba. It's my favorite. I guessed that PNW means Pacific North West right? That means I live in the GLCO (Great Lakes Central Ontario) ha ha. Good luck. Alec
Great videos Alec! Thank you so much for your honest and sincere tech tips! Perfect! Wish you health and flexibility of your mind Thank you for sharing 60 years of experience this is priceless
I would love if you would talk about different types of full face masks and the pros and cons of using them!! I love the videos and I'm an avid watcher, keep it up!
Hi Alex. Thanks for the vid. Excellent, as always. Was wondering if you do a comparison between PADI & NAUI dive courses. It's been 30 years since I last went diving & I'd love to get back into it. We are in northern Australia. Cheers.
I don't really want to get into an agency debate Ed. I'm an instructor for 7 different scuba training agencies and have friends in all of them. I think they all feel they are doing a good job. I will say this - PADI is larger is numbers and worldwide recognition than all the others combined! So it makes sense if you want to get back into the sport (or if you're just starting) to choose PADI. The knowledge and skills are the same for all of them but the training materials and methods and the universal recognition of PADI makes it the logical choice. NAUI was big in Oz as it was in Canada but they have simply not kept up with the times. Good luck. Keep in touch. Alec
Great informative videos and so well presented. Experience is priceless and thank you for sharing it. Like so many activities it does seem to me that buying the best you can afford is the only option, whether it's 2nd stage valves, face masks, BCDs and so on. Is there a range of equipment that competes with the very best in terms of functionality and performance without the flashy bits and what equipment do you use? Thanks again.
Greetings from South Africa, Been scuba diver since 1986. Great and informative videos. Keep up the good work. Am of the opinion that most of these "features" are gimmicks and the average diver does not really derive a whole lot of benefit from the apart from a lighter wallet ;)
Great video as always. I was getting ready to ask what kind of diver would want a venturi and you described my situation perfectly. Big bulky guy with a bit of a tummy, lol. Have you played around with those hydros pro bcd's? Would you recommend it? I'm eyeballing getting the hydros pro and a the mk25 s620 next year. The hard part is already figured out (the money) but that new bcd is a pretty unique design. Hoping it isn't an air2 type situation where it sounds good on paper, they upsell you it in the shop, but there is a fundamental flaw in the design like expensive to maintain compared to other back inflates or the material isn't as durable long term.
Surely the air speeds up when the lever is blocked, i.e.when the air passage is narrowed. This would cause the air to speed up in accordance with the Venturi principle. What say you ?
Good. My viewers are a mixed lot (in more ways than one). Some are new divers who just learned to pronounce regulator properly while others are very experienced divers with a lot of regulator experience including how to service them. I have to direct my videos at the common factor trying as much as possible to make them understandable without being too boring. Glad you enjoyed it. Alec
Great video as always. If a Venturi is sort of blasting air into the lungs, is it possible that it could increase the risk of overinflation injury to the lungs (ie pneumothorax etc) under certain circumstances?
I have never heard of a venturi causing a lung expansion injury. The volume of air is minimal but it's the 'push' that helps divers breath in easier. A
This is a little difficult to explain, but let me give it a try. When you inhale you create a negative pressure in the lung, or, better said, a negative pressure differential between your lungs and the ambient pressure, so the regulator responds by releasing air in order to compensate the difference. Whenever you stop inhaling, the negative pressure turns to zero and the regulator stops. If the regulator were to malfunction and freeflow, there would be a positive differential in the system and all the extra pressure would be released through the exhaust valve, just like when you start exhaling. If you can exhale through the regulator while it free-flows, than it cannot physically burst your lungs. It's like trying to inflate a bag with an exhaust flap. If the exhaust valve is stuck and you cannot spit the reg out of your mouth, only than you are screwd :D (you really cannot block an exhaust valve unless you duct tape it down from the inside).
Hi Alex, slightly off topic but what are your thoughts on the HOG line of regs and first stages, thinking of a HOG D3 and Zenith second stage? Love the videos super helpful and informative.
Thanks, Alec! It explained perfectly what happened to my regulator! So if I dive with max on my Venturi, does that mean I am consuming more airs and will likely run out of air faster?
Oh I`ll be asking questions , I tried to get into diving as a younster , Till my brother sold a motorhome we got Ieft all my gear in the compartment I was so choked , But I ended up being a big guy in my 50`s now but losing LBs again I know of a buy and sell link the people sell diving equip Cheap enough , Obviously if you have a 50 dollar life buy 50 dollar gear , But they have some nice Regs. Guages. BCD . for 100 to 500 should I consider this --I know of ( Don`t buy 6351 tanks ) Any tips
The most different second stages I know of are those by Poseidon. They're much smaller than most second stages, and the purge button is on the opposite end to the hose, rather than in front of the mouth. I know people who swear by them though.
I am new to diving and am taking my open water this coming Sat. My question is should I use their rental Dive Regulator or should I buy one. I did notice that during my 3 pool classes, some Dive Regulator seemed to be easier to breath.
If you want to continue diving, I hope you do, then owning your own gear makes it much more fun. Instead of a long message, watch S06E01 What to buy first/next/last. It will give your pointers to help you decide what and when to buy gear. Good luck. A
When you mix ton of charisma with years of experience you get Alec! Best scuba gear videos out there by far. Keep on good work! V
Wow! Thanks Voj.
Alec
What a great video! As a beginner these videos have been extremely useful in making me understand the equipment, and making me a better diver in the process. Thank you for sharing!!!
As a “big” guy who has been diving for ever, this was very informational and helps make sense. Plus after watching your video on your training (I took my course in 1974!) I’ve decided to go back this Spring and take a refresher. Even though I’ve been rec diving for years, taking time off and coming back, it really made me think and decide, why not take a course and make sure I’m “up to date” with my training. Thanks for these great videos Alec!
I smart decision Paul. May of us stone age divers have lots of dives but the new gear and training keeps you current, safe and enjoying diving longer. Stay safe my friend.
your content is superior ❤
Thank you very much. Hope you learned and had a laugh too.
A
Thanks ALEC for your explanation.I am 54 years and kind of the guy you just described even with the same regulator!!!! It is a very good help for all divers.Keep following yor tech tips
AH. A young diver.
Glad to hear you're enjoying my tips.
Alec
Man, you cleared all my doubts like anything. Best video on how the regulator works. Thanks. ton.
You're welcome Deepak. Lots more to learn.
A
I can't remember how many of your videos I've seen so far and I learned a lot from you some things I didn't know, I've been certified since 1989, and I learned your never to old to pickup something new. Thank you for sharing your passion I also have for diving. 🇺🇲👌🏼
Great to hear Rocky. Vintage gear is great fun to collect and dive but for easy no fuss diving, I love the modern stuff on my old bones.
I am so glad I watched this video and your excellent explanation about the venturi switch. I thought there was something wrong with my regulator. Now all I have to do is adjust the lever when my regulator starts blowing air and everyone is looking at me. LOL!!!!! Thank you very much.😊
You're welcome!
A
Great explanation again! Every time I watch your videos, even on a subject I thought I knew, you show me something I never knew before. I love your presentation style too, simple and to the point without any flashy green screens or animations, just a man in his workshop showing us the ins and outs with practical demonstrations.
Thanks for your uploads, haven't found a single bad one yet!
-Rob
Keep watching Wij. I'm sure there's a bad one in there.
Let me know when you fid it.
Thanks for watching.
Alec
You are the king of scuba! thanks for all the content!
I appreciate that!
Hi Alec, I just bought a new reg, a Scubapro MK11/C350. I just wanna say thank you, because I happen to watch this video just before my first dive with my new reg and could really understand about the venturi feature - and not panic when it easily freeflowed because I already know what made that happen - because of this video! Keep these useful videos coming!
Comments like yours are what make the work worthwhile. If I can help just one diver understand his gear better and maybe enjoy his dive more, I'm happy.
Thanks very much.
Alec
I love your channel. I'm getting back into diving after 23 years, since I was a teenager, and your channel has brought me up to date. Thx you and keep em coming....
That is awesome! Welcome back and hope my old man rants give you tips for buying gear and diving. Take care.
A
Thanks Alec. What you presented provide me with lots of useful information to better understand the workings of the regulator.
Welcome Ryan. Lots more for you to learn.
great explanation and most importantly, demonstration of the venturi effect in a 2nd stage. I came to this video trying to understand what a venturi caused free flow is and I learned so much more than that, including how a 2nd stage works. TNX !!!!
Glad you enjoyed it and are smarter for watching.
Thank you, Alec. I’m a new diver researching for my first reg purchase. This video explains well the need or not for venturi.
Glad it was helpful!
You, sir, are a mentor to a student like me. Thank you and Kevin for the time spent making these videos. Your contributions to all things diving are immeasurable.
You are very welcome John.
this has been the single most informative video I have ever seen, just watched it with my 12yr old boy who is doing his open water along with me, he now understands how the regulator works, what the parts are, and what a venturi does, brilliant video
Thanks Mark.
I'm glad it has helped you guys know what's going on.
Alec
You have a great talent for explaining things in a simple and understandable way.
I'm very fit but you never know what condition you could run into under water that might exhaust you (like being chased by the Loch Ness Monster ..lol ) and having that venturi can save your life. Worth the extra bucks.
Thanks sir, glad you enjoy my ramblings.
Hello Alec! Thank you so much for all your super informative videos. But this is one of my favorites! Wow, no one explains this as well as you do. This was a spectacular demonstration of the Venturi effect, which is basically the Bernounilli's principles of pressure differential in moving air ( the principle responsible for modern aviation). The rapid flow of air inside the diaphragm causing the pressure to drop significantly as compared to the pressure outside the diaphragm, and thus the diaphragm will continue to be "pushed" in as long as the flow is there. This principle applies to air flow within a narrow tube is called the Venturi effect allowing continuous air flow and thus helping the diver putting forth less effort on air-sucking. The manufactures called this Venturi-assisted, indirectly implying somehow they created this technology, but it is nothing more than the natural physics principle discovered by Giovanni Venturi in the 18th century. Closing the lever will partially close down the tube and slowing rate of air flow to the point the pressure in the chamber will rise enough together with the return force of the diaphragm back to its normally closed position, thus abolishing the Venturi effect. So the question is do we actually need this lever in the alternate second stage, commonly used only in an emergency? Probably not. Do we need the lever to prevent accidental free flow in the primary second stage when the purge button is struck, or when we need the Venturi effect to get more air with less effort? Probably. Your choice. It appears that the manufactures often charge hundred of dollars more to have this lever put in to their newest models, everything else being equal. Finally Alec, I am new to diving but watching your videos helped me learn a lot about this wonderful sports and save a ton of money at the same time, buy not purchasing unnecessary equipments!
Clearly your understanding of Bernoulli's Principle is solid and you're right. It's nothing new.
Re the design of regs, I agree that the venturi is NOT necessary in a safe second. In fact, it may cause more problems than any advantage offered.
I don't mind it in the primary provided it can be adjusted to minimal effect if wanted. When the diver needs some assist, he just dials it in.
DACOR (and maybe others) had a neat venturi system in which the lever had a vane on one side that directed the air across the diaphragm but only when the lever was depressed a lot. That is, with a normal shallow breath, there was no venturi effect but if you drew a big breath, as when you needed more air, the vane on the lever was drawn into the air stream and directed the air across the diaphragm to create a venturi effect. Essentially you automatically got a venturi asist when your needed it - automatically.
Glad you've been enjoying the vids.
Take care.
Alec
Great Video as usual. What you did not say in direct words (as you were talking to novices) was 'ease of breathing' although you certainly discussed it. In one article a tech diver said was that you can literally just take 3 breaths a minute (at rest) underwater. He was right. (7 second inhale, 7 second hold, 7 second exhale). I cannot do that on land! I attribute that to the light weightiness feeling in water and the EASE of breathing from the Venturi regulator. I have show students the difference in feel too, as you were showing on video with good, well maintained regulators vs some of the horrible ones I have seen used for pool use (and as rentals!). I do consciously try to do slow deep relaxed breaths while diving. As a result I have great deal more air than most of the group coming back. A venturi certainly helps. Full disclosure- I am a big guy and usually dive sidemount or with other gear/cameras- so more drag than most.
My test subject is always Kevin. He is a tiny diver just like a blue whale. He loves the venturi effect for his big lungs and slow breathing can make air last a long time.
Great tech tip-While watching I actually took my regulator apart and cleaned the diaphragm area. Will add to my maintenance agenda. Thanks, Jim
Thanks for watching Jim.
Glad it was helpful.
Alec
Very informative! Always a little smarter after watching your videos. Keep them coming, Alec! Thank you..
Thanks for another great episode. I know you have mentioned doing an episode or two on drysuits. Just wondering how that might be coming along. Thinking of taking that plunge soon and would love to hear your thoughts.
We should have that ready in January.
Alec
Wow Alec, great presentation. Very illustrative, mostly for somebody that is restarting to dive after more than 30 years of not doing it and needs to know how the equipment works nowadays. Keep on with the good work.
Most things haven't changed - new materials and some new technology. But we still fin up and down - not sideways (except for the odd tech diver) and have the same old problems -fogging masks, dives are too short, etc.
Have fun.
Alec
Non-diver preparing to go into diving here. Absolutely love the explanation and humour in this video. I know understand how this works! Thanks
Glad it was helpful and know you will love the underwater world.
A
I learned one more feature of my regulator. Thank you for your lesson.
Glad it helped
Just got a nice set of regs with these secondhand and had them overhauled. Thank you for making this.
Glad you like them!
A
Alec again thank you. A few years ago I bought a new reg set actually a ScubaPro set and spent a bit more than $800.00 on them. They have the venturi feature and until now I didn’t really understand the function. The only thing I knew is that the lever had to be off and then pushed forward when I was ready to start my descent. I thought that spending the extra money on the regs that the first and second stage where just better quality but now I understand that maybe I didn’t have to spend that kind of money to get a good reg set. Well too late for that now. I am totally satisfied with them and hopefully they will last me years to come. Keep up the great work with these videos as I am learning so much from them and I am becoming a well informed diver because of them. Hats off to you Alec and your no nonsense approach to things.
I'm glad I was able to enlighten you a bit Martial.
Don't be concerned about the few extra bucks to get a Venturi. It probably wasn't much and eventually, you may find it was a good investment. You have Scubapro regs so you'll have them for a long time. The day may come, with age or a perhaps certain dive situation, where you will be glad you have it.
Take care.
Alec Peirce Scuba your quick responses are also much appreciated Alec.
Love your content. I really appreciate the Venturi effect when diving in the 60m (180 ft) + range. As gas density increases with depth this has an effect on the WOB. The Venturi really helps with breathing dense gas mixtures.
Thanks for the feedback from a really deep diver.
A
I have found these videos so interesting. You go in great detail with all the gear and throw in some personal experiences while explaining which are very memorable and I can easily relate your suggestions to my own gear.
Thank you so much for doing this and sharing you broad knowledge on diving!
Well thank for watching.
I'm glad you're enjoying it. I enjoy making the videos or it that too obvious?
Almost every day someone asks why I don't make money on U-Tube.
My answer is simply - my viewers don't want ads and I don't want to spoil my fun.
Take care.
Alec
Thank you Sir....for another information packed video. Your delivery of the material and attention to details...make it a great way to learn. Please keep up the amazing work!
Much appreciated Michael and thanks for watching.
Greetings from Orlando Alec, glad to see another video! Hope you are doing well.
Thanks Scott.
Di and I are looking at getting a home in your area - around Little Canada in Kissimmee. Maybe we'll get together.
Take care.
Alec
That would be great!
Thank you Alec for all good advises..
I’ve only just discovered you and your tech tips. You are a revelation! I love watching your videos, you explain things in a way anyone could understand and you clearly have a LOT of experience. You also make me laugh a lot. Keep up then good work, I’m telling all my dive buddies about you!
Thank you Paul.
Hope you find something useful.
Alec
Excellent video Alec. One question, since you have shown us the way the assist functions, would you be willing to explain how/what is happening in the regulator when a diver uses the breathing adjustment knob as featured on your example regulator in this video? Best.
I can do that. Added to the list. Keep watching. It may be a while.
Thanks. Alec
Awesome presentation! Tons of charisma as well as expertise!
Thanks so much!
Hello Alec.Thanks for explaining that in laymans term. Short and concise, straight to the point..
Thanks Chris. Hope it helps your understanding of your scuba gear.
Alec
Alec, I have that reg. Mine on the venturi says surface or dive or something to that effect so I always thought it was just a free flow issue. It sounds like I am wrong from the video. Love the videos!
Some regs, Scubapro comes to mind, have a 'Pre-Dive and Dive' setting. Others might say 'Surface and Dive' or whatever.
Strictly speaking these are not Venturi settings but simply devices that attempt to eliminate the sudden FreeFlow from a second stage it it's dropped into the water or if the purge is pressed on the surface. In the case of Scubapro, it's just a small lever that keeps the diaphragm from being pushed inwards too far. Other regs use different methods but the intent is the same - on Pre-Dive you have less chance of a FreeFlow; on Dive you have the least breathing effort.
Just use it as suggested. Turn it to Dive after you enter the water.
Alec
This has been one of the most interesting, educational videos I've seen. Thank you!
Well, thanks Matt.
I have found (over 2 million views) that each video has something for someone.
I'm glad you found something useful in this one.
Alec
Alec, thanks for another great video. Keep them coming........
Alec
What an amazing video!! I bought a scuba pro MK25EVO and A700 reg a year ago and it has a Venturi on it. I found this Venturi useful on a dive on el um farod wreck in Malta, we were swimming back into quite a strong current and this Venturi helped a lot when I turned it on. I wasn't sure of the science behind it, I just knew it helped me. Now I know why!! Me and my 19 year old boy love your videos and think you're well cool, keep up the good work!!
Kind regards
Johnny Battiste
Thanks very much Johnny. I'm happy to be of some help on your diving.
Alec
Excellent information...love your videos...."your knowlege sails in a sea of experience...".😍😍😍
So nice of you. Appreciate it Miklu.
Thanks for the up-date Alex , life saveing air is to precious to be Liberal with it.........
thanks for posting............................
Alex
Great job on explaining how the Venturi does and how it helps out at diver. Keep the video's coming I miss not seeing one a week from you about fixing them. We live down in FL and started diving over five years ago in upstate NY. Diving in Lake George very cold around this time of the year. I'm glad we live in FL now on the west coast side.
Can you tell what a PADI or if NAUI tec course on maintaining your equipment goes through and is it worth it?
Thanks
Will
Diana and I are looking at getting a home in west Florida - in Little Canada close to Kissimmee.
The Equipment course is always a good idea. It mainly shows you how to take care of your gear so it lasts a long time. That alone is valuable besides the technical information you pick up about operation.
Take care.
Alec
You nailed the explanation of what i had diving this holiday against current. Had the Mares rover from dive center, but against the medium current it was a hard work for me and didnt give enough air for me.
Alec, your videos are a blessing! Thanks again.
Glad you like them!
A
I love love that vid Alec, really great and made me to understand even more the benefits and how to not have a free flow too easily ;) ... I have that exact reg 1st and 2nd stage except mine if the 50th edition bronze ...
Yep. Good reg.
Alec
Another very helpful episode. Thanks Alec!
Thanks for watching Glenn.
Alec
Your videos and explanations are priceless. Thank You !
Glad you like them!
A
Finally I get it!!! Thank you sooo much for sharing your knowledge with us!!
Glad to help. Scuba is simple but sometimes the explanations I hear make it complicated.
Alec
Thanks for the class on venturi I just bought a Brawn 1st, 2nd and octopus and they both came with this feature know I understand it a little better
Glad I could help
a divemaster in my open water training didn't even know what the venturi was, thanks for the knowledge
Not surprising Flyer.
Dive Gear knowledge is minimal for instructor training.
Alec
That's it I want a hooker system too. Sounds way funner than scuba!
Great video Alec! Thanks!
Able to do a video about water resistance testing on dive computers and how they test it in pressure chambers?
Few dive shops can do a pressure test. The test chambers are very expensive - $2000+. There's no way divers will pay enough to warrant having one. And you cannot test the computer functions, only the watertightness and even that's iffy.
If you've just installed a new battery and O-Ring and want to test it, the only way to know if it's watertight is to take it down in the test chamber while in water (easy to do) and then open it afterwards. If it's dry it's good; if it's wet it's ruined. And if it is dry, then you have to reseal it and repeat the above.
See? It's not as definitive as you might think.
The test chamber will check the depth and time readings. That's about it.
Any other dive computer problems can only be addressed by the manufacturer.
Alec
Great explonation! Thank you Mr.Pierce!
You are welcome!
A
Great video my friend. Pushing forward with my training to become an instructor. Bye spring I hope. Suggest a video: Are LED lights better than the old bulb type. And service your light. Maybe a video on transporting your tanks.
LED vs incandecent bulb - not even close. MUCH brighter and uses so much less power so smaller overall package, or longer life) and they don't burn out/break filament. He did a video (very useful) on why you want to remove your batteries between dives for storage. I ruined one cheap light not doing it. I remove them after each wkd dive now.
Lol😅. Dont get water on my 1st stage... Wow!! What more can i ask . A Million thanks Alec!!
LOL.
That's "don't get water IN my 1st stage" Marvin.
It's OK to get water ON your 1st stage.
Good luck.
Alec
Once again, you bring us a fantastic video. You truly are an awesome educator and presenter. Thanks! By they way, how is that video on painting or refinishing aluminum tanks coming along... (hint hint) lol. You are doing a great job!
Thank you. I love this video. Great job in explaining...
Glad it was helpful Monica. Thanks for watching.
What a great video. Excellent explanation for a newby like me.
Glad you enjoyed it!
Thank you Alec! Love the real demo of venturi and now I understand.
Glad you liked it!
That was an awesome explanation and show and tell
I'm glad it worked for you flyer.
Alec
As always great informative video
Thanks Chevy.
Alec
Beautifully explained! Thank you Alec !
Thanks for watching Aquanaut.
Take care.
Alec
Another great video. Thanks Alec.
Thanks for watching.
Alec
Hey Alec! That s a great video again. Thanks very much!
Thanks for watching Lulu.
Is that really your name or your U-Tube name?
And are you small, as in Little LuLu?
Take care.
Alec
Hey Alec,Nico is my real name ;)
Alec, I just got back from diving in Belize. Prior to my trip I had my regulator serviced (1 stage piston and the spring replaced, and the second stage had internals replace with the exception of the diaphragm). I have a scuba pro MK25 (1st Stage) with a MK x650 (2nd Stage). It has the lever for surface/dive modes with a knob for flow resistance.
While on the surface there are no problems. However, whenever I dive (~5-15 feet) the regulator will have a higher resistance as I start to breath in and it then "pops" and flow resistance drops. The problem occurs most of the time. I have tried adjusting both the lever and knob in various positions to try and correct the issue, but it not always corrects the problem. Even when I think I have the problem fixed and leave both the lever and knob in a given position at the end of a dive (where the problem appears to be corrected) it returns on subsequent dives.
I don't think there is an issue with the spring and piston on the first stage, but I could be wrong.
Any ideas as to what might be going wrong?
The meltdownman
It's hard to analyze a regulator without it being in front of me and on a test bench, even with your vivid description. I can say with some certainty that it is very likely the 2nd stage as you have already surmised. The 1st stage is a go/no go system. If it's working properly you get air. If it isn't, you don't.
The poppet & seat of the 2nd must be installed just right or performance will be sketchy. I suggest you take it to your dealer. Under the circumstance he ought to take care of the problem promptly & at no charge. It is likely a small matter but it is his responsibility. Parts are cheap so it's just a bit of his time.
Get back to me if the problem isn't rectified.
Alec
@@AlecPeirceScuba_SeaHunter Thank you for your response. I am learning more about equipment and how my gear operates better than any other teachings that I have come across in my 30 years of diving. You are a credit to the industry. Thank you and your staff for all the work you have put into your videos. You are all professionals.
Thank you again,
The Meltdownman
You're the BEST! Thanks again for a great video and explanations!
Houston TX
You are so welcome!
A
Thanks,
Alec, another great explanation. Your Tech Tips have saved me so much money, I was finally able to buy that ScubaPro G2. ;-) Well maybe not enough for the G2, but you have definitely decreased my annual expenditures significantly and increased the life and reliability of my gear. I really did get the G2 and love it, although I look a little odd diving with a G2 and twin steel 70s with a J-valve. Still looking for a twin hose regulator.
This is wonderful, love your explanation.
Glad you enjoyed it!
A
Hi Alec, Love your videos. I recently got recertified and have been watching you tech tips on what a person really needs. My son and daughter wanted to get me a regulator first and second stage for Christmas which they did. MK 25 Evo with a A700 reg. I told them it was way to much and over the top, but they insisted. I now need a safe second and would really value your thoughts on what to get. I am from the PNW and cold water dive, but will travel to Florida and Hawaii in the future. Thanks again.Scuba Pete
You can get a good octo from Scubapro if you like but I'm a fan of the specific safe second designs. Oceanic has one and Sherwood too. They are a lot less expensive, work as well if not better and are much easier to deploy in an emergency. Check out the AltAir from XS Scuba. It's my favorite. I guessed that PNW means Pacific North West right? That means I live in the GLCO (Great Lakes Central Ontario) ha ha.
Good luck.
Alec
WOW you just explain this so great !!!
Your should be a teacher.. now i see and hear how this works PERFECT !!! THX !!!
I am! I am a teacher!
Thanks for watching. Glad you enjoyed it.
Alec
always great to watch
Glad you like these Paulo, I love doing them.
absolutely a thrill to watch and learn about the Venturi lever, thank you so much! now i know why my regulator acts funny 😂
Regulators often act 'funny' but there's always a reason.
Thanks for watching.
Alec
Great demo with taking the cap off the 2nd stage
Glad you like it.
A
Great videos Alec! Thank you so much for your honest and sincere tech tips! Perfect! Wish you health and flexibility of your mind Thank you for sharing 60 years of experience this is priceless
Welcome Evgeny and thanks for watching.
Alec
I would love if you would talk about different types of full face masks and the pros and cons of using them!! I love the videos and I'm an avid watcher, keep it up!
I'm working on that.
Alec
Please show me the best way to clean and store my gear after diveing
Thanks Alex
There is an early video on that. I may do a new one.
Alec
Hi Alex. Thanks for the vid. Excellent, as always. Was wondering if you do a comparison between PADI & NAUI dive courses. It's been 30 years since I last went diving & I'd love to get back into it. We are in northern Australia. Cheers.
I don't really want to get into an agency debate Ed. I'm an instructor for 7 different scuba training agencies and have friends in all of them. I think they all feel they are doing a good job.
I will say this - PADI is larger is numbers and worldwide recognition than all the others combined! So it makes sense if you want to get back into the sport (or if you're just starting) to choose PADI. The knowledge and skills are the same for all of them but the training materials and methods and the universal recognition of PADI makes it the logical choice.
NAUI was big in Oz as it was in Canada but they have simply not kept up with the times.
Good luck. Keep in touch.
Alec
Just excellent!
Much appreciate the feedback.
A
Great feature it’s like having park assistant on your car.
Welcome D.A.
A
Awesome videos.keep them coming
Thanks Chris.
Alec
Would it be possible for you to talk about your opinions on full face masks and the pros and cons?
would be cool indeed
Just added it to the list.
Thanks.
Alec
Great informative videos and so well presented. Experience is priceless and thank you for sharing it. Like so many activities it does seem to me that buying the best you can afford is the only option, whether it's 2nd stage valves, face masks, BCDs and so on. Is there a range of equipment that competes with the very best in terms of functionality and performance without the flashy bits and what equipment do you use? Thanks again.
Love your videos
Thanks for watching Frank.
Alec
Greetings from South Africa, Been scuba diver since 1986. Great and informative videos. Keep up the good work. Am of the opinion that most of these "features" are gimmicks and the average diver does not really derive a whole lot of benefit from the apart from a lighter wallet ;)
Hello Marcel. Did you see my videos from South Africa? Starting at S06E17. Had a great time diving and safari.
Thanks a lot!
Very helpful. Keep it up
Very helpful explanation - thanks!
I have listened to many scuba "experts" trying to explain some scuba gear principles and been confused. I hope my videos help.
Alec
Great video as always. I was getting ready to ask what kind of diver would want a venturi and you described my situation perfectly. Big bulky guy with a bit of a tummy, lol. Have you played around with those hydros pro bcd's? Would you recommend it? I'm eyeballing getting the hydros pro and a the mk25 s620 next year. The hard part is already figured out (the money) but that new bcd is a pretty unique design. Hoping it isn't an air2 type situation where it sounds good on paper, they upsell you it in the shop, but there is a fundamental flaw in the design like expensive to maintain compared to other back inflates or the material isn't as durable long term.
Why not just get a backplate and wing? Hydros is like trying to be a little bit pregnant. Spend the savings on your octopus or air2.
Surely the air speeds up when the lever is blocked, i.e.when the air passage is narrowed. This would cause the air to speed up in accordance with the Venturi principle. What say you ?
Air speeds up at the constricted air passage as Giovanni Venturi predicted. How say you.
Thank you. Much easy to understand.
Good.
My viewers are a mixed lot (in more ways than one). Some are new divers who just learned to pronounce regulator properly while others are very experienced divers with a lot of regulator experience including how to service them. I have to direct my videos at the common factor trying as much as possible to make them understandable without being too boring.
Glad you enjoyed it.
Alec
Great video as always. If a Venturi is sort of blasting air into the lungs, is it possible that it could increase the risk of overinflation injury to the lungs (ie pneumothorax etc) under certain circumstances?
I have never heard of a venturi causing a lung expansion injury. The volume of air is minimal but it's the 'push' that helps divers breath in easier.
A
This is a little difficult to explain, but let me give it a try. When you inhale you create a negative pressure in the lung, or, better said, a negative pressure differential between your lungs and the ambient pressure, so the regulator responds by releasing air in order to compensate the difference. Whenever you stop inhaling, the negative pressure turns to zero and the regulator stops. If the regulator were to malfunction and freeflow, there would be a positive differential in the system and all the extra pressure would be released through the exhaust valve, just like when you start exhaling. If you can exhale through the regulator while it free-flows, than it cannot physically burst your lungs. It's like trying to inflate a bag with an exhaust flap. If the exhaust valve is stuck and you cannot spit the reg out of your mouth, only than you are screwd :D (you really cannot block an exhaust valve unless you duct tape it down from the inside).
Hi Alex, slightly off topic but what are your thoughts on the HOG line of regs and first stages, thinking of a HOG D3 and Zenith second stage?
Love the videos super helpful and informative.
I have used and sold HOG. Good stuff. Just be sre you can get service and parts where you live. They are not well known.
Alec
Very detailed tip!
Thanks, Alec! It explained perfectly what happened to my regulator! So if I dive with max on my Venturi, does that mean I am consuming more airs and will likely run out of air faster?
Using a venturi assist does not use more air but makes inhaling easier with less work so your more relaxed while diving. Thanks for watching.
Great chapter!! Alec, is it usefull to have a venturi if you use a fullfacemask?
Wow that was informative Thanks Alec .
Thanks again.
Alec
Oh I`ll be asking questions , I tried to get into diving as a younster , Till my brother sold a motorhome we got Ieft all my gear in the compartment I was so choked , But I ended up being a big guy in my 50`s now but losing LBs again I know of a buy and sell link the people sell diving equip Cheap enough , Obviously if you have a 50 dollar life buy 50 dollar gear , But they have some nice Regs. Guages. BCD . for 100 to 500 should I consider this --I know of ( Don`t buy 6351 tanks ) Any tips
Thanks a million, finally I get the idea.
Fantastic Video. Thanks for that :)
Thanks Easy.
Alec
The most different second stages I know of are those by Poseidon. They're much smaller than most second stages, and the purge button is on the opposite end to the hose, rather than in front of the mouth. I know people who swear by them though.
Everyone has a favourite they love. That's why we have so many choices in gear, lucky us.
A
I am new to diving and am taking my open water this coming Sat. My question is should I use their rental Dive Regulator or should I buy one. I did notice that during my 3 pool classes, some Dive Regulator seemed to be easier to breath.
If you want to continue diving, I hope you do, then owning your own gear makes it much more fun. Instead of a long message, watch S06E01 What to buy first/next/last. It will give your pointers to help you decide what and when to buy gear. Good luck.
A