Now i know that sword frogs and gorgs pikclips and stuff exist. Honestly this all comes down to aesthetics and i'm not a whole lot concerned with min-maxing although it does involve a good bit of that.

Basically i'm look to add a sheathed sword to my garb. I have experience making kydex and wooden sheaths but basically what im looking for is some guidelines about the smallest (circumference-wise) roughly 30" blue you guys can think how to make. Do you reckon it'd just be a 2.5" min bat or could a single edged flatblade get smaller (again, curcumference-wise)? my basic plan is to build the weapon, measure the circumference, go out and buy the pvc pipe that most matches that measurment. Then heat it up and stick a wooden version of the sword into it to form the shape.

If anyone sees any major flaws with this idea im really all ears. I don't wanna go make something just to find a fatal flaw that i missed and injure someone else or myself.

A small bat would have a smaller circumference than a sword. Assuming the typical 1.5" blade width and the minimum 3" flat width for the template exception, you'd have a roughly 9" circumference for a flat blade sword. A 2.5" bat would have a circumference of about 7.8", but you'd want to go up a bit to allow for compression of the foam as the weapon is used. It would still come in slightly smaller.

Aesthetically, I'd go with the flat blade sword. It won't protrude as much as the sheath for the round bat would, and will have a flat side that will be more reminiscent of an actual sheath. Diameter wise, you're looking at a ~2.75" bat v.s. a ~3.25" sword.

As far as molding the PVC, I can't see where that would be problematic. As long as it isn't pointy or dangerous, and doesn't have sharp edges that could cut or tear your weapon, you should be fine. You could even get some thin suede or scrap leather and glue it into the PVC, and make it look like a hardened leather sheath.

very much appreciate your reply.
do you think it'd be possible to make a single edged flatblade with a 2.5" flat that doesnt fail template?

If the tip was very slightly rounded, that might work. If it doesn't meet the 3" exception then the tip cannot pass more than 1/2" through a 2.5" hole.

What I've done is take fabric slightly longer and wider than the sword, line it with fiberglass strapping tape then sew it loosely around the sword by hand. The plastic coating of the tape keeps the friction on the fabric sword cover down so its easy to draw. Plus when the sword is not in the sheath it hangs loosely without getting in my way like an over sized belt flag.

The Gorg blackmarket sword has a 2 and 5/8" profile. That's the thinnest I've seen around.