How do I join 2 neoprene sheets in a sharp 90 degree angle?

I'm creating a neoprene casing to a small product and I'd like it to have a rather straight and stiff appearance, almost like a molded detail.
For that reason I don't want to use normal seams (flatlock, overlock) to join the sides of the casing as it would cause bulgy surfaces or a too wide radius.

How is this done in the industry? Could it be done either like alternative 1 or 2 in the picture? Which one is to prefer and which joining method is preferable (sewing, glueing, tapeing)?

All ideas are welcome!

Picture of How do I join 2 neoprene sheets in a sharp 90 degree angle?
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rickharris8 months ago

karolina81 (author)  rickharris8 months ago

That's a great video, thanks for sharing.

Your welcome.

steveastrouk8 months ago

PS. In industry, its probably welded, either by direct thermal methods, or ultrasonically.

karolina81 (author)  steveastrouk8 months ago

OK, but then I don't understand why they don't weld wetsuits? Or do they?

A wet suit isn't waterproof.

No chance to get the glue or tech they use to do it on a home level.

Downunder35m8 months ago

IMHO the boest option would be by cutting like in pic 2 and then to sew nylon tape over the joined area woth enough overlap.
If you want to glue to give added strength and such I recommend contact shoe glue.
The sutff stinks like hell, takes about 2 hours to dry but if you join two covered surfaces at this stage you only have one attempt to get it right.
Once together the things stay together for good. as usually the fabric gives up before the glue does.
For coarse stuff like neoprene it helps to use a small spatula to work the fresh glue into the material so it is in all tiny holes, cracks and such and not just on the top surface.

karolina81 (author)  Downunder35m8 months ago

Ok thanks for the tip! Maybe the nylon tape should be melted with a heat gun/iron afterwards?

steveastrouk8 months ago

Is it intended to be water tight ?

karolina81 (author)  steveastrouk8 months ago

It should be fairly watertight, however not drysuit-watertight. I should definitely seal the seams with more than stiches.

iceng8 months ago

That is a Wet suit problem go to a local dive shop and see how thy make neoprene boots sewing and glue including a zipper..