Advice for making a lexan fin

[Aziara]

So the nearby lowes has a sheet of 28" x 30" x .093" lexan. I taped paper together at home in the same size, and sketched my monofin/fluke. I'll also be buying some flexible plastic tubing, 1/2" sliced lengthwise and slipped onto the sides as support (also as "bumpers", if I accidentally whack anything), and some 3/8" tubing for the other veins.http://i1147.photobucket.com/albums/o554/Aziara86/photo-14.jpg
i do have a couple of questions.
Is there any reason that most monofins put your ankles so far apart? Is there anything wrong with me making a single neoprene 'bootie' that fits both feet together? Or does the space between the feet help with the dolphin kick?
To get the shape I want with the size, I ended the pattern where the arch of my foot begins. I also like the semi-extended look it gives. Due to using neoprene for footpockets as I mentioned earlier, heel to arch of my feet will be flexible. Will that badly affect my swimming?

[MerAnthony]

There are a few people out there that make a monofin just like you explained with a single bootie. An from what I have heard that they work pretty well.

[Aziara]

Awesome! Good to know. Thanks.

[Mizuko]

Love the fluke design! :D Cant wait to see how it all goes!

[Mermaid Momo]

I think having the actual fin start at the arch of your feet may be problematic when trying to do the dolphin kick because you'll basically be using only the strength of your toes. I think bringing the fin up a bit (keeping it as thin as you like) to the heels of your feet will give you Better propulsion and the fin won't flop awkwardly around because your feet will hold it stable.

[Aziara]

Hmm, yeah I see what you're saying. A downstroke would be ok, but an upstroke might be difficult because it would pull my feet along with it (I don't have strong arches to begin with). So I might only get half as much propulsion... Pooh.
I might have to find a pair of short zoomer fins. I could bolt them on at the very edge and still have stiff stuff under my feet. *thinking*

[Aziara]

Well, I found a pair of $5 swim shoes at walmart today. I got them a bit small just in case they stretch in the water. All the real swim fins were pretty expensive, not to mention I've never actually worn a pair of swim fins that didn't hurt my feet somehow. I'm gonna try attaching them a bit more forward on the lexan, so that my heels will be at least partially against it. As much as I like the look of a long fin, I like good propulsion better :)

[MerMarla]

Aziara,

I have several fins that are cut in different locations along the bottom of my foot, and the ones that have an edge under my arch are covered with 3/8 inch or more of neoprene. I thought they would be ok, but they still cut under my arch. They make my dolphin kick a bit uncomfortable. I love where my Weeki fins were cut, which is just to the back of the heel pad, exposing only your heel. We used regular fins made from Voit back then, so I just transferred the placement of where they cut the fin to my newer ones. Works fine, doesn't cut my arch or heels. We didn't have rubs using rubber fins, either. Maybe fins were made better back then...

One reason, I suspect that Monofin manufacturers place the ankles farther apart is chafe, you don't want your ankles rubbing. Another reason is simply anatomy. If you stand with your knees together and be as straight as you can, you will see that your natural tendancy is to have your ankles a bit apart. It comes from the width of your pelvis, and the angle thru your knees. You could force your ankles to touch but would be awkward to swim that way. Most ppl are not perfectly shaped, and even rubbing your knees in a Tail will become quite uncomfortable if you do it long enuf, speaking here from experience! So keeping your ankles a bit apart, and not rubbing the insides of your knees is a good thing. You could make a "test tail" out of cheap $5 /yd spandex (I get bathing suit lining material at Jo-Ann Fabrics, then use a 40% off coupon to get the fabric, about $3 per yard), and swim in it. See if you like the spacing you made, if not, take it in a little. Rather than cut your good fabric, this is a cheaper way to decide your pattern shape.

I think propulsion is better too, over looks!
Good luck!
Mermaid Marla

[Aziara]

Thanks for weighing in, MerMarla. Good to hear (and learn from) your experiences. I don't think my ankles or knees will rub, as using the swim shoes puts my ankles an inch or so apart. Seeing as I don't actually have any neoprene, I've scraped the idea of making a neoprene 'foot pouch'.

[Jinx]

The foot pressure to water pressure resistance ratio can be way off that way. Speaking from experience I know that causes at least 2 issues. The pressure being off can cause your lexan to crack and 2 you will definitely end up with blisters from trying to get enough propoltion and they hurt.

[Miyu]

I was also thinking of making a monofin in a similar manner; I am very short in the leg and Don't want a stump tail; also, I like the look of the "POTC" type of fluke, where it's not so mammal-looking. The monofin I want is $355, and I can't afford that, so I'll be looking for some flexible but durable plastic sheeting or some rubber, and some of those $5 water shoes. I may make the plastic bump up against my heel, as MerMarla suggested. I'm taking inspiration from this thread and the "Sirena" monofin from this seller (http://www.etsy.com/shop/CustomMermaidFins?ref=l2-shopheader-name), but making it to the shape I like. I think the "Sirena" has a good area size for propulsion, at least from what I saw in the demo video - I've never swam in a monofin before, so I don't really know what I'm looking for, other than how it looks being used. I like the neoprene pocket idea to blend the feet into the fluke a bit more!

[Gem Stone]

i'm using cut lexan and duct tape for the foot pocket, and it works wonderfully. I've actually had people ask to buy my homemade monofin

[Jinx]

I'd stay away from too much duct tape gorilla glue has a tape that is 100% water proof and I wore shoes covered in it on a walk under Niagarafalls cavd of winds. You can't get a better test of durability than that. Also the water shoes tend to give me blisters as they don't come in half sizes. If you can find pair that fit like a glove use them but I think if you go to dick's sporting goods or somewhere similar you might find something better. I would even suggest finding a shirt or shorts from under armor, cutting and adhearing it to the lexan . Under Armor is really stretchy and so you can make a nice tight foot pocket that won't wiggle around and will be comfortable as well.

[Miyu]

Hmm, I'd been wondering about the waterproof-ness of duct tape; I know it's alright for temporary applications but I have duct tape peel on me all the time and I figured it would do so underwater for me as well, and I don't feel like replacing it all the time :P Good to know that Gorilla Tape is extremely durable, I hadn't had the chance to test any yet, and it's more accessible than neoprene here anyways (plus, I've head neoprene stretches over time). Under Armour is also a great idea! I'd been playing around with the idea of wearing a pair of Under Armour leggings under my tail to avoid legs/knees/ankles showing too much - I read somewhere that some mers wear tights underneath, and I think I saw a Weeki Wachee mermaid wearing striped tights while getting into her tail. I think maybe a pair of leggings = a foot pocket made out of a shirt would make a really nice look! And thanks for the head-up on the water shoe sizing, I'll make sure to try on a few different sizes then - my feet are wide and my toes are long, so I have a hard time finding shoes LOL.

[Gem Stone]

duct tape, if applied to itself and when completely dry, is completely strong and water proof. Mythbusters made a boat out of duct tape. but it has to be dry, and the right kind of tape, and you have to take good care of it. but my foot pockets aren't completely duct tape, just most of it:p

[ShyMer]

I wouldn't think that most fabrics would be a good idea, personally. Anything that stretches much is going to wear out with use. Stretchyness is going to prevent you from getting the maximum propulsion out of the monofin too. If the footpocket is loose, you have to work harder to move the energy to the fin, and the way I see it, fin swimming should be all about efficiency.

If your monofin is really floppy, you might get away with a stretchy footpocket, but if it's stiff like mine, you need something more secure.

I guess I'm not sure about using duct tape for the foot pockets either. Maybe it depends on your design. One advantage would be that you could mold it to fit your feet.
I tried using duct tape to repair my rapid's footpocket once and it would not stick for anything. Maybe I just had a cheapo brand or something.

[Jinx]

I wouldn't think that most fabrics would be a good idea, personally. Anything that stretches much is going to wear out with use. Stretchyness is going to prevent you from getting the maximum propulsion out of the monofin too. If the footpocket is loose, you have to work harder to move the energy to the fin, and the way I see it, fin swimming should be all about efficiency.

If your monofin is really floppy, you might get away with a stretchy footpocket, but if it's stiff like mine, you need something more secure.

I guess I'm not sure about using duct tape for the foot pockets either. Maybe it depends on your design. One advantage would be that you could mold it to fit your feet.
I tried using duct tape to repair my rapid's footpocket once and it would not stick for anything. Maybe I just had a cheapo brand or something.
Which is why under armor is the way to go. It is a compression garment so it doesn't stretch it just puts pressure. It is perfect for this application.

[Miyu]

I'm planning on making the actual footpockets out of swim shoes, then cover them with something (under armour) to blend the feet into the fin, like the Sirena monofin. I also like the floppiness of it, do you get that with lexan or is it too stiff? I'm also worried about kicking someone or something with a stiff fin.

[Jinx]

Not really at least with the thickness you needed for not having it crack.

[Miyu]

Gotcha. Well then I'll be looking at all the materials at Home Depot when I can haha... back to the drawing board.

[Jinx]

If you look online sometimes you can find colored Lexan way cheap if you aren't worried about translucentcy.

[Aziara]

I'm planning on making the actual footpockets out of swim shoes, then cover them with something (under armour) to blend the feet into the fin, like the Sirena monofin. I also like the floppiness of it, do you get that with lexan or is it too stiff? I'm also worried about kicking someone or something with a stiff fin.
I've got my monofin partially completed, and it is somewhat flowy in the water. So much so, that I took the center portion that I cut off, turned it around, and bolted it to the base where the feet are for extra stiffness

[Miyu]

LOL! Good to know it's flowy. I was considering making a "support structure" for the foot area as well. Nice to know how yours turned out, thanks Aziara! Of course, I'd love to see it in action :P

[Aziara]

Whew... I kinda left this for a while, finally started working on it again. I've got it mostly finished now. I'm wondering, has anyone ever tried using lumiere paints on rubber or lexan? It would be nice if parts of the fluke could match my tail.http://i1147.photobucket.com/albums/o554/Aziara86/photo-18.jpg (http://s1147.photobucket.com/user/Aziara86/media/photo-18.jpg.html)