I'm not very handy...but I want to build some panels

I use regular, thick zip ties from walmart to bind the frames together. The original Steve Helm design for the frames used another piece of drywall bead but that's overkill and makes disassembly more difficult. The panels also have friction between them so that helps. I've never had a panel slip out and they're two layer sandwiches. Not to mention the flange on the bead helps.

You want to find studs to hang the panels but I always just use drywall anchors. If your ceiling is particularly flimsy like mine, use the metal mechanical anchors. I've had my ceiling panels up for years and zero flex. I'm using 8lb mineral wool but OC might be even better.

Panels:
1. Buy rigid panels.
2. Buy fabric.
3. Buy vinyl drywall bead, hole puncher, zip ties, and 1/8" rivets. Good scissors help and so do work gloves, long sleeves and mask.
4. Cut drywall bead to size - frame edges overlap at corner (I alternate over, under) - two frames per panel.
5. Punch two diagonal holes at each frame intersection and affix rivets.
6. Cut fabric in a rectangle matching panel face plus thickness.
7. Cut fabric diagonally from corners from edge to panel to facilitate folding.
8. Fold fabric onto panel using a bit of spray glue on the sides if wanted.
9. Optional: Cover the back in the same way. I leave mine uncovered.
10. Affix frames to panel with zip ties - three per side.
11. Hang panels from zip ties or attach chains through or around ties.
12. Review original plan: www.radford.edu/shelm/acoustics/bass-traps.html

Super chunks:
The frame is triangular. As per the video, I cut each drywall bead segment on an angle so they fit. Otherwise the square flanges will prevent mating.
I can then rivet the parts that intersect.  This is for the ends, not the legs.  Legs are just plain and straight.
The bead has holes and the tie wire goes through them - not 'around' the entire frame legs.
The chunks are 4' high. 2' up, I make an inner support triangle which is attached to the frame legs. This part faces up.
Basically, I used R-19 which is 6" thick and 24" wide. That means I had to make wire 'shelves' on the top, bottom, middle, and three more each 2' half.
Mainly, use your imagination how to wire it up. I think I did a big loop through the leg holes then made that taught with another circle wire.
Honestly, you could also use door screen or chicken coop wire too. Tie wire was probably just cheapest.
Also, if I could do it again and space permitting, I probably would've made 2' rectangular soffits instead of triangular chunks. Why? More absorption.
Further, budget permitting, rigid super chunks will probably work better. They'll also be heavier. Not sure how the drywall bead will hold up to the weight of all that stacked rigid. Fluffy works, however.

Hopefully that helps. That super chunk video was one of my first and I could probably make it better now. Super chunks can be labor intensive, though, so we'll see how I handle future acoustic challenges.

Availability varies depending on your location but try checking with local building supply companies. Sounds like you already have. If you can determine the manufacturer of the mineral wool from Grainger, you should be able to get acoustical data on line etc. Hopefully you can avoid shipping. Here in the Chicago area some big box home centers have mineral wool in stock.

So I tried to look up the specs for the Roxul Model # 40225 that Grainger has. Seems it's not that easy to drill down but you should contact grainger and roxul and see if you can get specs. Even if you can't, my guess is that it will probably work fine. There's a range of acceptable densities and it's really not that critical. 

6" is good. Have you tried bay insulation?

www.bayinsulationsupply.com/

$150 for shipping isn't terrible assuming you get all the insulation you'll need for life. I have 20 panels plus superchunks but I could easily double the number of panels. Depending on your goals, 40 6" panels wouldn't be overkill.

I'm no craft builder myself so maybe someone else can help. Another option is making the panels thick enough so they're stackable. That's probably what I'll do if I ever make 8" panels. Making stands, while convenient, definitely adds to the cost.

Looking great