Parachute effect with fin and bootie fit. Added bonus: How deep should these booties go into the fin?

[HamTrainChickenLaser]

I've come across an interesting issue. I've been watching youtube to understand how booties and the foot pockets of my fins are supposed to go together and I wonder about exchanging a pair of Deep 6 Eddy fins. First, here is the video that made good sense to me:


If anyone disagrees with the assertions being made in the video please feel free to comment. Parachuting or the parachute effect seems to be an issue for a person who wants to frog kick and glide, or anyone else really. You don't want your foot pocket to cup the water and fight against you. Also the degree to which the bootie penetrates the foot pocket seems important. Here is where it gets complicated for me.

These are probably in deep enough, but I don't want them to stick out of the fin any further:

As you can see this is the XL size. These OM Gear 5mm booties are a size 12. I wear a size 10 1/2 wide in normal street shoes for the most part, or sometimes 11 wide. My running shoes are Brooks Adrenaline 12.5 EE, but of course running shoe sizes are wacky. At any rate, if I go a size smaller then probably my bootie will stick out further and I don't think I want that. I think any further OUT of the foot pocket will not be a good fit. On the other hand, here is the parachute creating drag:

Now that is with the bootie pushed all the way to one side.

And pushed to the other side.


And there is a 12 second video for you.

This is probably OK as far as how much the heel sticks out, true?

These strike me as fabulous quality by the way. STURDY. I'm about to travel for my rescue diver and deep diver courses so getting prepared!

I also wonder if a thicker bootie is the answer- something more substantial. But same issue crops up there- I don't want to lose penetration to take away sideways play.

 

[HamTrainChickenLaser]

Not sure how these would fit but might be a solution:

 

[inquis]

Overthinking it WRT "parachute drag". Water is incompressible, so on the recovery stroke, the "block" of water in the pocket acts like a brick pushing other water out of the way. On top of that during the glide, the pocket is hidden by your torso.

I'm assuming your pictures are representative of the insertion when you're actually wearing them. Your foot is inserted far enough for leverage. If there is no side-to-side floppiness, you're good.

 

[HamTrainChickenLaser]

Overthinking it WRT "parachute drag". Water is incompressible, so on the recovery stroke, the "block" of water in the pocket acts like a brick pushing other water out of the way. On top of that during the glide, the pocket is hidden by your torso.

I'm assuming your pictures are representative of the insertion when you're actually wearing them. Your foot is inserted far enough for leverage. If there is no side-to-side floppiness, you're good.

Good points, and here is another video with my feet in the booties which does take up some of the slack:


There is some friction against my fingers- it's not a sloppy fit I would say.

I think I'm good. Also, in my world there is no "overthinking"- there is only thinking. LOL

 

[KenE]

I believe the "parachute" effect is overrated. As @inquis mentioned, water does not compress like air and therefore the "parachute" effect is not accurate. The key is to get a snug fit where your bootie has sufficient penetration and no side to side movement when worn on your foot. Looking at size and fit without the foot in the bootie is not a good representation of fit. The likelihood of getting sufficient penetration and filling the foot pocket completely is fairly low, some folks will get it and others will not. This is the science of foot pocket design to maximize the number of bootie sizes accommodated without having many different size pocket designs.

 

[Zef]

As a "rule of thumb", if when you have your bootied feet in your fins, with your straps on your heels and you pick up a foot and shake/pivot it from side to side, if the fin moves around your foot then it is too big.

Obviously with an unrestricted budget of time and money, one could order and/or try fins ad-nauseum until one finds the "perfect fit"...but most divers will try on a bunch and settle for the "good enough fit" that strikes the balance between overall fit, overall comfort, price, and availability.

-Z

 

[HamTrainChickenLaser]

As a "rule of thumb", if when you have your bootied feet in your fins, with your straps on your heels and you pick up a foot and shake/pivot it from side to side, if the fin moves around your foot then it is too big.

Obviously with an unrestricted budget of time and money, one could order and/or try fins ad-nauseum until one finds the "perfect fit"...but most divers will try on a bunch and settle for the "good enough fit" that strikes the balance between overall fit, overall comfort, price, and availability.

-Z

Good point on shaking and pivoting, and my fin does not move when I do that. Thank you!