CETMA S-Wing SWing footpocket stretching / molding - Step by step

[HoneyBadger]

When searching for footpocket stretching / molding, I've never found a step by step for CETMA's S-Wing footpocket or any general procedure that didnt involve a heatgun, hairdryer or sliding the foot with layers of socks inside the 100C/ 212F heated footpocket so I hope this approach* will help solving the foot pain/ discomfort for some of you.

Context: CETMA's sky-boot design has several high stiffness bands that will keep your foot tightly fitted and will avoid energy dissipation due to rubber deformation. This is great but it becomes painful after 20 minutes on the "intermediate cuneiform bone" - this is the inner part of the foot where it is arched the highest.

I wish CETMA could mold a left and right footpocket considering this relevant anatomical detail. Until this day comes, follow the steps that worked for me.

Step by step (Disclaimer: do it at your own risk )

1. Find a heat resistant object to stretch the area that you want. This candle glass had the right measurements and worked perfectly.

2. Place it inside the footpocket and secure it in place to avoid dislodging the candle glass while the footpocket is in the pot with boiled water

3. Boil the water, turn off the fire, and place your footpocket inside the pot.
3.a. Timing is a case by case basis so check and adapt. In my case, the first footpocket I've done two rounds of 5 minutes and the second footpocket, one round of 10 minutes with the same outcome
3.b. If required, tilt the footpocket inside the pan depending on the area you want to have it molded/ stretched.
3.c. NB: Virgin olive oil is used for illustration purposes only

4. Remove it from the pot and let it cool (with the candle glass still inside the footpocket) for 20 minutes.

5. That's the before and after - with the bulged section

*6. Additional thoughts and notes:
6.a. This approach may be better suited for thermoplastic rubber which is the case of CETMA's S-Wing. If the footpocket material is 100% rubber, it may not hold the stretched section after it cools off.

7. Enjoy a pain/discomfort-free training session!

 

[Mr. X]

Excellent post. I didn't realize that you could stretch footpockets until somebody posted about it very recently. Good to have some details and a successful example.

I usually recommend folk err on the side of slightly large. Then you at least have the option of wearing thicker neoprene socks; I suppose padding and insoles might help too.

I was very lucky, I was able to try on my first of spearo fins - Beuchat Competitions 45-46 - and they have proven to be an ideal fit for me and my stocky feet: when it is very warm, my feet swell and they become tight so I dive without socks, which is cooling too , when it is very cold, my feet shrink and I can wear thicker socks if I want to

Consequently my spare set of fins are also Beuchat Competitions 45-46. I had buy fins on location last year, Apnea 45-46 which are well known to be very large for stated size - and these are quite baggy/loose but usable; I probably should have bought a smaller size but it was difficult with social distancing and stock off-site. I could look at padding them some how but they are just spares now. I should probably sell them on.

 

[HoneyBadger]

Excellent post. I didn't realize that you could stretch footpockets until somebody posted about it very recently. Good to have some details and a successful example.

I usually recommend folk err on the side of slightly large. Then you at least have the option of wearing thicker neoprene socks; I suppose padding and insoles might help too.

I was very lucky, I was able to try on my first of spearo fins - Beuchat Competitions 45-46 - and they have proven to be an ideal fit for me and my stocky feet: when it is very warm, my feet swell and they become tight so I dive without socks, which is cooling too , when it is very cold, my feet shrink and I can wear thicker socks if I want to

Consequently my spare set of fins are also Beuchat Competitions 45-46. I had buy fins on location last year, Apnea 45-46 which are well known to be very large for stated size - and these are quite baggy/loose but usable; I probably should have bought a smaller size but it was difficult with social distancing and stock off-site. I could look at padding them some how but they are just spares now. I should probably sell them on.

Tks Mr. X,

I think the above stretching approach works better with thermoplastic rubber (which is the case for CETMA's S-Wing). 100% rubber may be more resilient - but would be nice to have some additional feedback on this.

I was lucky as well with my previous no-frills/ heavy-duty plastic Subgear fins which had a perfect fit and that's ideal considering I usually dive in warm waters and don't need to condition the fin usage with an additional pair of socks. After the stretching, CETMAs is now in the same category.

For high-end fins, I think the footpocket sizing options will improve in the future with smaller increments e.g. 43, 44, 45, 46 etc. Till this date comes, we'll have to rely on some workarounds.

Cheers

 

[mmal]

I personally use a different method to mold my S-WiNGs.

First off: I size down one size when buying the footpockets. When it comes time to mold I wear 3mm booties and, with the footpockets on my feet, use a heat gun to slowly heat up the hot spots around my foot (usually around the top of the foot) not applying direct heat to any one spot for too long, but distributing the heat across the entire pocket... I do this in stages, with a large bucket of room-temperature water next to me to dunk the foot in when it gets a bit too hot. I will heat the footpocket until it gets a bit hot, dunk my foot into the room temperature water until my foot cools off again, then pull the footpocket out of the water, dry off, and begin the heat it up again. I make sure to wiggle my foot around inside the footpocket as it's being heated.

This method makes for a 100% perfect mold to the shape of the foot. The results are incredible. You end up with a footpocket molded to your exact foot shape. Just make sure to mark the right and left, so you don't get them mixed up.

 

[HoneyBadger]

I personally use a different method to mold my S-WiNGs.

First off: I size down one size when buying the footpockets. When it comes time to mold I wear 3mm booties and, with the footpockets on my feet, use a heat gun to slowly heat up the hot spots around my foot (usually around the top of the foot) not applying direct heat to any one spot for too long, but distributing the heat across the entire pocket... I do this in stages, with a large bucket of room-temperature water next to me to dunk the foot in when it gets a bit too hot. I will heat the footpocket until it gets a bit hot, dunk my foot into the room temperature water until my foot cools off again, then pull the footpocket out of the water, dry off, and begin the heat it up again. I make sure to wiggle my foot around inside the footpocket as it's being heated.

This method makes for a 100% perfect mold to the shape of the foot. The results are incredible. You end up with a footpocket molded to your exact foot shape. Just make sure to mark the right and left, so you don't get them mixed up.

Hi Mike, tks for sharing. I have just read and replied to your post on Facebook. Glad to see more people documenting different approaches and that it worked for you. Cheers

 

[pena23]

Looks great.

 

[mmal]

I'm going to revise my original post here, with the post I made on Facebook. See below:

Is molding your footpockets worth it? In the top part of the first photo, the left side is an unmolded CETMA S-WiNG, the right side is molded to my right foot. The bottom is two molded footpockets.

The process is a bit cumbersome, but worth it when you come out with a perfectly fitting, custom molded pair of footpockets.

You need:

• a pair of footpockets made of thermoplastic rubber (like the CETMA S-WiNG)
• a heat gun, a bucket of water big enough to fit your foot with the footpocket on
• towels, and socks that are 1-2mm thicker than the socks you plan to wear when diving (or 2mm socks if you plan to dive bare foot)

If you plan to use glue to mount the blades to the footpocket, this can only be done PRIOR to mounting blades.

The process: wear the footpockets, with your socks on, for the entire molding process. Do one foot at a time.

With your heat gun on medium/low, heat the area of the footpocket that is causing a pressure point. For most people, it’s the top bridge of the foot.
Keep the heat gun moving constantly, don’t let it sit in one spot for too long. With the S-WiNG pockets, there are tendons that wrap around two parts of the foot. Usually the top tendon is the part you want to focus on. Make sure to heat the entire tendon, all the way around the top of your foot.

Scrunch your foot up during the entire process to stretch pocket out. It will naturally begin to form to the shape of your foot.

Once you start to feel the area you’re focusing on getting warm, dunk your foot in the bucket of water and let it completely cool off. Make sure to do this EARLY. Remember you’re wearing a layer of insulation... if you wait til your foot is hot, you’ll end up burning yourself. No bueno.

Repeat this process as many times as needed to get the pocket molded, without burning yourself. It takes me about 5 rounds.

Once the pockets are molded, let them sit in a well ventilated areas for at least 24 hours (the longer the better, I normally let them sit for 72 hours) to completely dry out prior to mounting blades.

If you screw this process up, I take no responsibility. It’s not rocket science. If you have any questions, send me a message.

 

[mmal]

Also, obviously, remember to mark one of the footpockets so that you now which goes on which foot.

 

[marco15499]

Interesting. I've used boiling water succesfully. It takes like 15 minutes and the results are great. Bring water to boil, turn the heat off, put the footpockes in for 5 minutes, take them out and wear them with your socks moving your toes eventually until they cool down. Voila'.

 

[musubi]

Apparently I didn't search well enough to find this thread, so I posted one on Spearboard about me molding my S-Wings there:

S-Wing Foot Pocket Molding - Spearboard.com - The World's Largest Spearfishing Diving Boating Social Media Forum

S-Wing Foot Pocket Molding Non-Gun DIY Projects and Customizations

www.spearboard.com

There's also a video about molding an S-Wing.

Seems like everyone has their way of doing it. For me it was putting on some socks, putting the foot in the pocket, then heating with a heat gun. Then using a water hose to cool it off. Made a big difference in comfort and also visually. I could see where the pocket now re-formed to the shape of my foot. Up top and on the sides.

After my first round of heating I tested the fit in a pool with the blades now installed. Overall comfortable, but I started developing an ache/cramp in my right foot. I later found that my right foot was slightly larger (wider) than my left. I repeated the process on heating and widened the pocket some. I'll be testing again to confirm it's all good.

A little off-topic, I used Pathos foot pockets for years. Fit fine and never gave me cramps, but after wearing these S-Wings, I can really feel the positive difference in support. The rubber on the Pathos (latex?) was too soft on top and at the vertical heel part, so I always relied on ankle straps when I dove. This softness also caused me to place a lot of pressure on my phalanges part of my foot, which created sore pressure spots when diving, which I'm realizing now isn't normal.
The S-Wings are definitely heavier than the Pathos Fireblades and caused some concern for before actually trying in the water. I no longer see it as an issue since it translates to better support (and durability I hope).

HoneyBadger, what blades are you pairing with your S-Wings?

 

[HoneyBadger]

Apparently I didn't search well enough to find this thread, so I posted one on Spearboard about me molding my S-Wings there:

S-Wing Foot Pocket Molding - Spearboard.com - The World's Largest Spearfishing Diving Boating Social Media Forum

S-Wing Foot Pocket Molding Non-Gun DIY Projects and Customizations

www.spearboard.com

There's also a video about molding an S-Wing.

Seems like everyone has their way of doing it. For me it was putting on some socks, putting the foot in the pocket, then heating with a heat gun. Then using a water hose to cool it off. Made a big difference in comfort and also visually. I could see where the pocket now re-formed to the shape of my foot. Up top and on the sides.

After my first round of heating I tested the fit in a pool with the blades now installed. Overall comfortable, but I started developing an ache/cramp in my right foot. I later found that my right foot was slightly larger (wider) than my left. I repeated the process on heating and widened the pocket some. I'll be testing again to confirm it's all good.

A little off-topic, I used Pathos foot pockets for years. Fit fine and never gave me cramps, but after wearing these S-Wings, I can really feel the positive difference in support. The rubber on the Pathos (latex?) was too soft on top and at the vertical heel part, so I always relied on ankle straps when I dove. This softness also caused me to place a lot of pressure on my phalanges part of my foot, which created sore pressure spots when diving, which I'm realizing now isn't normal.
The S-Wings are definitely heavier than the Pathos Fireblades and caused some concern for before actually trying in the water. I no longer see it as an issue since it translates to better support (and durability I hope).

HoneyBadger, what blades are you pairing with your S-Wings?

Tks for the video Musubi. I'm using the Mantra CWT Competition.

 

[GarFishChris]

Tks for the video Musubi. I'm using the Mantra CWT Competition.

I'm going to revise my original post here, with the post I made on Facebook. See below:

Is molding your footpockets worth it? In the top part of the first photo, the left side is an unmolded CETMA S-WiNG, the right side is molded to my right foot. The bottom is two molded footpockets.

View attachment 56995

View attachment 56996

View attachment 56997

The process is a bit cumbersome, but worth it when you come out with a perfectly fitting, custom molded pair of footpockets.

You need:

• a pair of footpockets made of thermoplastic rubber (like the CETMA S-WiNG)
• a heat gun, a bucket of water big enough to fit your foot with the footpocket on
• towels, and socks that are 1-2mm thicker than the socks you plan to wear when diving (or 2mm socks if you plan to dive bare foot)

If you plan to use glue to mount the blades to the footpocket, this can only be done PRIOR to mounting blades.

The process: wear the footpockets, with your socks on, for the entire molding process. Do one foot at a time.

With your heat gun on medium/low, heat the area of the footpocket that is causing a pressure point. For most people, it’s the top bridge of the foot.
Keep the heat gun moving constantly, don’t let it sit in one spot for too long. With the S-WiNG pockets, there are tendons that wrap around two parts of the foot. Usually the top tendon is the part you want to focus on. Make sure to heat the entire tendon, all the way around the top of your foot.

Scrunch your foot up during the entire process to stretch pocket out. It will naturally begin to form to the shape of your foot.

Once you start to feel the area you’re focusing on getting warm, dunk your foot in the bucket of water and let it completely cool off. Make sure to do this EARLY. Remember you’re wearing a layer of insulation... if you wait til your foot is hot, you’ll end up burning yourself. No bueno.

Repeat this process as many times as needed to get the pocket molded, without burning yourself. It takes me about 5 rounds.

Once the pockets are molded, let them sit in a well ventilated areas for at least 24 hours (the longer the better, I normally let them sit for 72 hours) to completely dry out prior to mounting blades.

If you screw this process up, I take no responsibility. It’s not rocket science. If you have any questions, send me a message.

Hey Mmal,

Thanks for the detailed response. I am wondering why "If you plan to use glue to mount the blades to the footpocket, this can only be done PRIOR to mounting blades"?

I already have my s-wings glued on to the blades sadly. I have tried with a hairdryer and have made some traction, but not as much as I was hoping for.

Cheers

 

[musubi]

Hey Mmal,

Thanks for the detailed response. I am wondering why "If you plan to use glue to mount the blades to the footpocket, this can only be done PRIOR to mounting blades"?

I already have my s-wings glued on to the blades sadly. I have tried with a hairdryer and have made some traction, but not as much as I was hoping for.

Cheers

My guess is it's not only easier, but would form-fit better without the glued blades.

That said, my blades are glued in and I made adjustments after they were glued in. Maybe you need to add more heat. Just be careful with heating and stretching too much since the pocket won't shrink back.