SUPER low volume mask modification

[Apneaddict]

Agreed that plasticine or other putty is a great way to test.

Once confirmed - use the Sugru, as it has all of the properties of silicone that we love (temperature resistance, chlorine / salt water resistance, strong bond, etc).

I had thought of doing the same thing... But got restless over the winter and said screw it, get it done!

I also didn't look forward to a piece of silly putty dislodging at depth / compression and bouncing around into my eye on the ascent.

 

[Apneaddict]

Got some depth practice with this creation this weekend. the water was between 2* and 6*.

The first dive I had it on fairly tight and held my nose the entire time and went to the bottom of where we were diving (-24m) without having to equalize at all!! . My Sporasub Mystic required an equalization around 5M and again around 15M or so.

The second dive I fitted it more loosely and pre-equalized the mask at the surface and again held my nose the entire time... But this meant that there was more void space to begin with and it required an equalization around -18m.

The cool part is that the volume that needed equalizing was so low that all I had to do was let my nose go with my hand and the vacuum stole air from my nostrils and it automatically equalized the mask without me having to blow any air out!! That has never happened to me before.

This is the second time that I have concluded that the logic of "wear the mask lightly to increase its compressibility" theory is BS. I have to equalize masks significantly less often when I tighten them up and reduce the overall volume as much as possible.

SUPER happy with the testing and hope to take it much deeper in the next couple of months.

Excited to see how adjusting the fitment at the surface affects it's equalization and curious to see how deep I can go without equalization.

On the first dive to -24, I feel that I could have taken it to -35 or -40 before equalizing. The pressure wasn't great and I was shocked that I didn't need to give it air even once.

On the second dive the pressure built much faster and at around -14 was quite strong and by -18 was high and needed air.

The visibility for line diving is great and I never felt that I needed or wanted any additional peripheral vision.

A fairly new depth diver joined me and he tried a sphera and did not need to equalize it at all to the bottom as well - but he removed his hand from his nose I believe.

Stay tuned - as I have another mask gem up my sleeve and it could be VERY interesting - I'm excited!!

 

[baiyoke]

Hey. Great to hear you're happy with the mask. Especially that the airspace is so tiny, that even a very little amount of air is enough to equalize it...

Now, once again, I hate to be a party spoiler, , but there's no way you can beat the laws of physics... You can't make a mask less compressible by putting more air into it at surface... It's true that if filled with more air, the change in size will be bigger... but a one point the size wil be the same, as if you put less air in it. You don't change the physical properties of the mask by putting more or less air in it, so you cannot possibly go deeper because you put less air in it from surface. The things you mention can probably be attributed to one of two scenarios: a) It could very well be, that air is escaping the nose unnoticed on descend. This is especially likely since it takes only a small amount as you say, and it seemed to happen to your friend also as you mention. Or b) it is attributable to psychological factors: A more loose mask might feel like it gets more tight quickly, because the size-change is bigger.

This is the second time that I have concluded that the logic of "wear the mask lightly to increase its compressibility" theory is BS. I have to equalize masks significantly less often when I tighten them up and reduce the overall volume as much as possible.

Now, what works for you I shall not comment on. But from a scientific perspective, looking only at the airspaces, there's no way making a smaller airspace form surface should improve depth adaptability, since you will anyway meet that same tight fit a few meters below surface. It must be mental or something about technique...

 

[Apneaddict]

I am not suggesting that the laws of physics do not exist underwater or do not apply to me. In fact, I am quite well versed in them.

What I am suggesting, is that by tightening up the mask more on the surface, I bring my cheeks and face into the mask more and not only reduce the static volume, but I achieve a result that is not achieved at depth by wearing it looser / with more void space on the surface.

As you understood earlier in the thread, eliminating void space with the silicone spacer made the mask more "compressible", even though the skirt got firmer.

By tightening the mask, I fill the void further with my face / cheeks more - and from that point they act as dynamic spacers on the way down in a way that is not possible with a mask that is fitted loosely at the surface.

The "theory" of a looser mask being more compressible makes sense, but assumes that a face is a regular solid mass and doesn't in itself react to pressure changes or a pressure gradient.

I am only putting this out there so that someone who believes everything they read on the Internet and only tries a super-loose mask (because it's supposed to be more compressible and should require less equalization), might try cinching it down and see for themselves if they like it better and works for them / their face and mask combination.

The theory is great and I am intelligent enough to understand it - but the practical application is often compounded by other factors that are not taken into account.

Lab vs. real world.

Also, in the 24m example with the tightly-fitted mask... Air did not escape to equalize it, as I held my nose the whole way down.

 

[Apneaddict]

found a cool pic online:

http://www.freediveblog.com/wp-content/uploads/2012/03/Low-Volume-Mask-Silicone.jpg

I did previously try taking an Omer Alien mask that I had and electrical taped it so that only a small hole was open - but really didn't like the tunnel vision.

I suppose at some point I will try it though... and likely use a Micromask (or M-99 copy) with 2 little nickel-sized holes and the rest all packed tight with Sugru.

I will likely use some plastic tubing set in there from the nose pocket to the eye-holes to form a channel, as I would want to make sure that the air used in equalizing actually goes to the void space that I want to equalize and doesn't get blown out of the mask entirely. I'm thinking aquarium tubing to act as a spacer until the silicone starts to set... you can use soapy water as a release agent.

I'm also thinking that with a mask with this little volume, that an overly large nose pocket can actually increase the compressability significantly, just from a volume ratio standpoint... even if you pinch it the whole way down.


Speaking of compressability - I ran across this online as well:
New Pocket mask by SUBGEAR | Only One Apnea Center

http://onlyoneapneacenter.files.wordpress.com/2013/03/pocket_mask_adv.jpg

Looks interesting - maybe for recreational use where you want good visability and still compressability and even to fill with silicone, as the mask appears to be able to bend around the bridge under compression!

 

[rddk]

sorry but all of this work cuz equalizing is the main problem, wouldn't be a better solution to work hard on equalization rather than modify your equipment? I have a micromask and am able to go 30+ metres on frc dives with the mask on so i think that improving the tecquniche is a lot better than try stuff on equipment. If you wanna do a competition or a one shot deep dive goes for googgles and you won't feel cold in just one dive. I often do my trainings in a lake that is really cold and in one shot dives i never feel cold and i use a 3 mm wetsuit too

 

[Apneaddict]

Hi rddk,

Thanks for weighing in with your thoughts and comments.

I can answer your inquiries in several ways:

1) you are likely just simply a better Freediver than I.

2) rest-assured, I am in fact also working on my equalization, as well as breath hold, CO2 tolerance and flexibility in parallel.

3) I did not spend a lot of time on the modification - in fact with this write-up I suspect than anyone could duplicate it in less than :20 mins. I could make another in less than :10.

I found the changes very helpful and spent much more time actually documenting and writing it up on here to share with others, for their benefit (as I already have my mask done!).

4) this was started because I have a very narrow face and a sphera doesn't fit and even with the Micromask, there was extra additional void because of my narrow face, so I wasn't getting the same benefit as others with this mask.

If a 1/2 or 2/3 scale sphera had existed, I never would have gone down this route - but more on this later.

5) why do you choose to wear the Micromask and and not something like this??:


I just took it to the next level / made a further round of improvements that met my needs.... Which leads me to:

6) I wanted a very low-volume glass-lensed mask with good visibility for safety (to undo possible entanglements) and silicone coverage for the forehead / sinuses, as I was in 2* an 6* surface temp water last week. This mask allows great upwards and downwards visibility without having to move the neck (important to reduce chance of trachea squeeze).

Liquid goggles do not meet these needs / criteria even remotely.

The mask volume is one of the airspaces that needs to be equalized upon descent and seeing as that air is not available to us once we put it in, until we start ascending again, I want to put in as little as possible.

7) some people like to tinker / tweak / personalize / optimize their equipment for their own needs or physiology - I did this when I raced cars and gained significant competitive advantage.

Others stick with off-the-shelf and do just fine.

8) seeing as I live in Canada and my depth diving is very limited for about half the year locally, I did have time to think about my depth plans and how to make my diving and reaching my target depths easier.

Hope that helps answer your inquiry.

All the best,
Apneaddict

 

[rddk]

I use the micromask because is a low volume mask is a great advantage in freediving. My intention was just to say that actually the difference between a micromask and a micromask filled with silicone is minimal so why risking to destroy an expensive stuff? I mean does few cc of air makes so much difference? That was my 2 cent opinion and wasn't just a show off of my low freediving abilities

 

[rddk]

Sorry if i'ven't express myself in a correct and clean way

 

[baiyoke]

What I've learned from this thread this (my personal thoughts): Low volume IN ITSELF matters very little, and if you master the trick of inhaling on ascend, bigger might even be better... When low volume does matter, it is mostly in the ease of mask equalisation on descent, not in spared air, wich is a rather tiny amount, that will not affect how deep you have to mouthfill (unless the mask is huge). I can see how it might be nice though, when doing fx many repeated dives, allthough not really nescesarry as I see it... But most importantly: It works for Apneaddict, so whatever works for you works...

However, volume relates to something that does matter: compressibility ratio. So to modify a mask ideally you would need to make it more compressible measured by a ratio. And this might be achieved by making the volume lower, in such a way, that it doesn't affect the ability to compress mechanically.

But rddk of course have a point in that it's important to practice good equaization also... But one does not rule out the other...

However it really matters more on very deep dives, since you can theoretically go to 80m even if with a kind of "average" skills/flexibility (mask equalisation at 20m, before mouthfill at 25m, before RV at 30m). If I'm correct, I think the calculations below illustrate that:

A compressibility ratio of 3 (sphera on my face about that I think), and equalization at 20m = 80m, 1/((1/3)/3) = 9 atm = 80m

A compressibility ratio of 4, and equalization at 20m = 110m, 1/((1/3)/4) = 12 atm = 110m

(funny how for every ratio gained 30m is added with this mask equ. depth of 20m, i.e. ratio 2 = 50m, ratio 3 = 80m, ratio 4 = 110m ratio 5 = 140m and so on...)

But I must say I'm impressed by the very little volume and high compressibiity ratio Apneaddict has made, it might make things less stressfull during those important first 30 meters on a deep dive, if mask only needs a little air to equalize, and does so effortlessly...

 

[Apneaddict]

If Martin366 and Baiyoke didn't inquire about how deep it could go without equalization, I wouldn't have measured the compressibility and just used it.

If I just used it and it worked great, I'd have (incorrectly) assumed that it was directly related to volume and not compressibility.

It isn't initially intuitive that by adding stiff silicone to a mask, you can increase its compressibility ratio.

I suspect that this effect is most dramatic on already low-volume, glass lensed masks, like the Micromask.

If the Mares Star or Omer Zero3 fits your face well, I believe that these masks can benefit equally, as they both have weird "horns" that are void space that won't ever compress. Many other masks will benefit as well.

With the right (wide?) face, a Zero3 will work awesome, since the skirt is super-firm and there is some significant void spaces to be filled.

Another thing I learned in this process is that on a firm-skirted mask, I benefit from wearing it tight and scrunching up my face and putting it INSIDE the mask, as opposed to wearing the mask looser and on the OUTSIDE of my face.

I get much more compressibility with my face inside the mask and letting it act a a dynamic spacer as depth increases.

This may not apply as equally to a "flexy" mask like the Sphera, flow mask or "SubGear Pocket Mask", as with these you are really relying on the silicone skirt and / or plastic lenses to "give" and create the compressibility. I'll let Baiyoke experiment with his Sphera to see if the gains are worth it. It will vary by face though.

 

[baiyoke]

Another thing I learned in this process is that on a firm-skirted mask, I benefit from wearing it tight and scrunching up my face and putting it INSIDE the mask, as opposed to wearing the mask looser and on the OUTSIDE of my face.

I get much more compressibility with my face inside the mask and letting it act a a dynamic spacer as depth increases.

That's an interesting idea... Difficult to comment on the mechanical properties... Only thought that popped up in my mind, was that if the skirt was full of some slippery gel, it might be able to suck in the face, even if mask is fully inflated at surface... Doesn't sound good though he he...

 

[Apneaddict]

Finally got my hands on the latest piece of kit.

It's a child's mask!
I wanted a 2/3 scale Sphera to fit my narrow face... And after lots of searching found something close to that definition.

It's made by Aquasphere and I'd more accurately describe it as a 1/2 sized cross between a Sphera and the Flow mask. It's known as the Reef in the USA and the LIZ in Australia and Europe.

If it doesn't work well for me, it'll make a kid really happy.

It's got a single lens, but has a frame around it (albeit of very flexible silicone), so I hope that the optics / clarity of vision is retained better then the flow mask.

It doesn't collapse as much as the flow mask, but still compresses nicely. I may do some measurements on it next week and get it in the pool then as well.

You will need nothing larger than a "small" nose... "button" preferred to fit into this mask.

 

[growingupninja]

If Martin366 and Baiyoke didn't inquire about how deep it could go without equalization, I wouldn't have measured the compressibility and just used it.

If I just used it and it worked great, I'd have (incorrectly) assumed that it was directly related to volume and not compressibility.

It isn't initially intuitive that by adding stiff silicone to a mask, you can increase its compressibility ratio.

I suspect that this effect is most dramatic on already low-volume, glass lensed masks, like the Micromask.

If the Mares Star or Omer Zero3 fits your face well, I believe that these masks can benefit equally, as they both have weird "horns" that are void space that won't ever compress. Many other masks will benefit as well.

With the right (wide?) face, a Zero3 will work awesome, since the skirt is super-firm and there is some significant void spaces to be filled.

Another thing I learned in this process is that on a firm-skirted mask, I benefit from wearing it tight and scrunching up my face and putting it INSIDE the mask, as opposed to wearing the mask looser and on the OUTSIDE of my face.

I get much more compressibility with my face inside the mask and letting it act a a dynamic spacer as depth increases.

This may not apply as equally to a "flexy" mask like the Sphera, flow mask or "SubGear Pocket Mask", as with these you are really relying on the silicone skirt and / or plastic lenses to "give" and create the compressibility. I'll let Baiyoke experiment with his Sphera to see if the gains are worth it. It will vary by face though.

Interesting thread, thanks for posting. I recently got the Omer Zero 3; definitely an improvement of about 20%-30% in max depth over my previous Super Ochio, right out of the box. The mask is less comfortable though, as I can wear the Super Ochio all day for days on end, but the Zero 3 starts to hurt my forehead after about 2 hours. Not a big deal though as I use them for fishing and that extra depth provided by the Zero 3 is not anything my legs can sustain for a full 2 hours of spearing.

HOWEVER, I've been using the Zero 3 on some line dives, and one of my buddies when I lent him the mask noticed that there is actually a lot of extra space in the tip of the nose. I may try something like this to fill it up. I am not sure why the mask was designed that way since the nose piece doesn't seem designed to compress with pressure, unless they just wanted to make sure the mask would fit more faces.... I also like to EQ my mask, and pretty much never ever ride a mask. Probably a comfort thing, and it may also be related to my EQ (I've always used BTV, and for my deepest dives usually take my mouthfill around 100').

I have used Sugru on some projects as well. It's good stuff...

 

[Apneaddict]

I actually think that extra space in the nose piece is an advantage, as this volume will compress with pressure - much more so than any other part of the mask. The Zero3 doesn't really compress due to the firm (and small) skirt.

I wouldn't fill this void space up personally.

Depending on mask volume and your nose size, the nose can be 10-25% of the total air volume when on your face.

I'll take that free compressibility!

Re: the Zero3, there might be a small space in the upper corners that you could fill, but might now be worth it for a few CC's.

An extreme example would be to glue some balloons into the main airspace of the mask and just inflate them with your nose prior to diving. If you did this with 4 large ones in a small mask (like my modified micromask), in theory you could go VERY deep without equalizing it - like 50-80m deep or beyond!

 

[growingupninja]

I actually think that extra space in the nose piece is an advantage, as this volume will compress with pressure - much more so than any other part of the mask. The Zero3 doesn't really compress due to the firm (and small) skirt.

I wouldn't fill this void space up personally.

Depending on mask volume and your nose size, the nose can be 10-25% of the total air volume when on your face.

I'll take that free compressibility!

Re: the Zero3, there might be a small space in the upper corners that you could fill, but might now be worth it for a few CC's.

An extreme example would be to glue some balloons into the main airspace of the mask and just inflate them with your nose prior to diving. If you did this with 4 large ones in a small mask (like my modified micromask), in theory you could go VERY deep without equalizing it - like 50-80m deep or beyond!

Interesting what you say about the nose compressing. I will do some deep drops and feel around to see what's going on. I am pretty sure they nose piece does not compress at all though--this based on putting on the mask dry and sucking air out of it.

This thread has reignited my interest in pipe goggles. I have a pair I made a while back but they had two main issues--they fogged horribly, and they leak. I think my problem was that I bought a pair of goggles and built them into a pipe mask before I'd really tried to see if I could wear them as is without them leaking. As a swimmer I have worn the $3.50, super low profile Swedish goggles my entire pool life and been very happy with them, I may try to build some of those into a pipe mask. My other issue with the pipe mask in general was having a tube in my mouth (I don't even use a snorkel, ever), but then I got the idea of combining a nose plug with the EQ valve (basically it would work like a mask then). I made a test nose plug/eq tube thingy out of Sugru actually but it wouldn't stay in. I only just the other day tried regular nose plugs and realized that I could stick a flattened tube in one nostril and clamp it in with a regular nose plug, so I'll try that. I EQ BTV so needing to close nostrils is not an issue for me.

The fogging problem is vexing. I think it's just going to be an issue with any plastic lens. If I could get a tempered glass ovals that I could inset into my swedish goggles it might solve that.

 

[azapa]

Check this micro mask out, I ended up with 66ml volume, and a being able to see. I have taken this 65m deep, without packing.
http://forums.deeperblue.com/threads/best-freediving-mask-for-glasses-wearers.96291/

This year I swapped to a nose clip for competitions, it was painful, but I have done it now. No real depth improvement though. I believe in retrospect that I was using the masks volume as a third lung, taking air from it past RV. Don't ask me to explain too much as I still don't really get it, but deep equalization seemed easier with the mask, I was very efficient at the last few frenzels. Now, with the clip, EQ is easier in the first 3/4 of the dive, but trickier in the latter part. Sorry, a bit of a ramble!