DIY Silicone Monofin

[Finny]

Hey all, It's been a minute since I've posted here, but I was curious if anyone here has made their own silicone monofin.
I know some places like mertailor do their own in-house and I think it's within my skillset to do, it just seems a bit overkill, especially for a fluke design probably not a lot of people would want afterwards (if I have the mold I could always cast them for people kind of deal).
I do have a 'proper' monofin but I find it sort of uncomfortable and think it might make me not want to use the tail, which would be kind of crappy seeing as they're pricey to make.
Other bonus of a full silicone fluke would be more natural looking movement in the water which would be cool.

Or for those of you who have silicone monofins vs. the hard plastic or fiberglass ones - which do you prefer & why? Particularly if you're swimming in the ocean.

Thanks <3

[Merman Storm]

I have a Mertailor tail with a built in silicone fin. I also have FinFuns, and tails with monofins that I have made using sheets of plastic bolted to swim fin pockets. The stiffness of the plastic has gone all the way from soft to very stiff.
They all work. I have swam in the ocean with all of them.
In terms of propulsion, the Mertailor is quite good, second only to my Lunocet, despite being quite soft. One thing to know: The foot pockets are made with stiffer silicone, with a duometer of 40. That stiffer part extends aft of your toes by several inches. The rest of the fin is the typical durometer 10 silicone used for the tail skin.
The really stiff fin swims quite differently form soft ones. With a soft fin, you decide how it moves. With a stiff fin it tells you how to move. (This mainly applies to how you move your ankles). Also, I had to bend the fin to make it work at all, as I cannot point my toes very well. The monofin industry has caught on to this issue, and are now making "angled monofins".
Comfort: The Finfun is of course comfortable, as are those I have made, as I can get swim fins with foot pockets that fit me. The Mertailor was terrible, making horrid red marks on my feet. It was so bad I fought the fit while wearing it, trying to get some relief, and tore the monofin. After repairing it, I carefully trimmed the offending parts away, rounding some corners, and now it is comfortable.
Suggestion if you make your own: Make the foot pockets in the shape of feet, not a square box.

[OrcaMatt]

I'd err on the side of a little stiffer than normal (relative to most silicone flukes) shore strength if you're swimming in open water. You're going to want the propulsion. I have an FF4 and it's great but I'm not sure I'd want to swim in the ocean with it on those grounds. The fluke in my avatar pic is 'monofinless' silicone and it's WAY too floppy to be safe in open water. Looks great, though, the few times I've seen it used. Just bump up the shore strength of your silicone mix.

[Finny]

Thanks for the info guys
I think my plans evolved a bit since posting this to where I could theoretically and with *relative* ease make custom build silicone fins for a person's actual foot instead of generic sizes :P If I did go that rout my plan was to use either 40-60A short hardness stuff for the monofin itself and reinforce it with powermesh & perhaps some dragon skin on the outside since it's the most durable of all the silicones available.