Here is the fly pattern sheet for the OB2Wanchironomie.

Black/Silver version
Materials
Hook:
TMC 2487 or Dai Riki 135, #12 – 16
Gills:
Oral B dental floss
Bead:
Size 11 transparent or silver-lined orange bead
Thread:
Black, Danville or UTC 70 denier
Rib:
Silver, small wire
Body:
Black krystal flash

Black/Red version
Materials
Hook:
TMC 2487 or Dai Riki 135, #12 – 16
Gills:
Oral B dental floss
Bead:
Size 11 transparent or silver-lined orange beads
Thread:
Black, Danville 6/0 (70 denier) or UTC 70 denier
Rib:
Red, small wire
Body:
Black Krystal Flash
Other Versions

Red Butt/Brown version
Materials
Hook:
TMC 2487 or Dai Riki 135, #12 – 16
Gills:
Oral B dental floss
Bead:
Size 11 transparent or silver-lined orange beads
Thread:
Black, Danville 70 denier or UTC 70 denier
Butt:
Red holographic tinsel, small
Rib:
Silver, small
Body:
Medium brown holographic tinsel

Chromie (using Glamour Madeira for Gills)
Hook;
TMC 2487 or Dai Riki 135, #12 – 16
Gills;
Oral B dental floss
Bead;
Size 11 transparent or silver-lined orange beads
Thread;
Black, Danville 70 denier or UTC 70 denier
Rib;
Red holographic tinsel, small
Body;
Medium silver holographic tinsel
Directions
- Pinch the barb; slide the orange glass bead on the hook.
- Start the thread behind the hook eye. Attach a ¼-inch piece of Oral B dental floss (round instead of flat) so it forms a bow-tie.
- Secure the bow-tie and push the bead firmly against the floss; keep it in place by making four or five turns of thread behind the bead.
- Whip finish and cut thread.
- Using a permanent black marker, darken the top and bottom of the bead.
- Trim the bow-tie so each side is about the length of two hook eye widths. The bow-tie gills look a lot more natural than the traditional gill tied facing straight over the hook eye.
- Start thread again behind bead.
- Tie on rib and wind thread down hook, keeping rib on side of hook. Continue part way down bend of hook.
- Wind thread back to bead.
- Tie on 2 strands of Krystal flash or 1 stand of tinsel.
- Wind body material to point where rib begins half-way down hook and back to bead. Secure and trim.
- Wind rib forward and tie off.
- Use thread to create smooth transition from body to bead, whip finish and cut thread.
- Coat fly with UV resin or Sally Hansen’s Hard as Nails
“This chironomid pattern borrows the bead/gill combination from the Garcia’s Rojo midge. I replaced the Rojo’s red bead with an orange bead hence its name – OB 2 (orange bead, Oral B dental floss for gills). The orange bead imitates the brown wing pads of the midge pupa. To get the skinny profile for size 14 and 16 flies, I use Krystal flash, Flashabou, and holographic tinsel for body material.” Bill Seitz
Glass bead: Spirit River Hi-lite small, transparent orange beads or silver lined glass beads, size 11.
Note: I’ve used a product called Glamour Madeira as a substitute for the Oral B dental floss wings. I think either will work.
Glamour Madeira #8 wt, color 2400, Opal/Prism White