Starting on my first true tank

[Barb T]

The set is just a smidge under 7". My son's 32" kilt, with 34 pleats, has 8.6 yards of fabric

That makes sense - 7x34 = 238", or 6.6 yards. Add 2 yards for the apron and underapron, and you have 8.6 yards. Sounds like about 1/2" pleats at the hips.

If the fellow you're making the kilt for has a 46" waist, and his hips are at least that big, you'll need at least 46 pleats across the back to have them be 1/2" pleats at the hips (more than 46 pleats if his hips are bigger than his waist). But assuming 46 pleats, 46x7 = 322", which is essentially 9 yards. Adding 2+ yards for the apron and underapron means that you'll need more than 11 yards for this kilt. Hope you have that much on the bolt!!

And remember that it's the hip circumference that you need to worry about, not the waist circumference, when matching the pleats to the existing band kilts and figuring out how much tartan you need.