The Stone Stack
One bead makes you choose. Weight and profile ride on the same part, so you cannot add a tenth of a gram without also changing the head of your fly.
The Stone Stack is three components that share a through-hole and nest together on the shank. Weight, profile and color stop being the same decision.
Tear Drop
Tungsten body that slides on like a slotted bead and carries the mass in the thorax, then tapers into the body. This is where the weight comes from. Six sizes, 2.0 to 4.1mm.
Stones
The head. Tungsten, slotted for jig and heavy streamer hooks, round for standard nymph and curved hooks. Twenty-three colors.
Bug Band
Machined brass, about a fifth the weight of a tungsten bead the same size. A hotspot and a fine weight adjustment rather than a weight source. Thirteen colors.
The weights, in grams
Raw tungsten. Paint and matte finishes add about a hundredth of a gram.
| Size | Slotted | Round | Tear Drop | Bug Band |
|---|---|---|---|---|
| 1.5mm | 0.03 | not made | - | - |
| 2.0mm | 0.05 | 0.05 | 0.10 | - |
| 2.4mm | - | - | 0.19 | - |
| 2.5mm | 0.11 | 0.10 | - | 0.02 |
| 2.7mm | - | - | 0.29 | - |
| 2.9mm | - | - | - | 0.04 |
| 3.0mm | 0.21 | 0.18 | - | - |
| 3.2mm | - | - | 0.40 | - |
| 3.3mm | - | - | - | 0.07 |
| 3.5mm | 0.33 | 0.30 | - | - |
| 3.6mm | - | - | 0.53 | - |
| 3.7mm | - | - | - | 0.09 |
| 4.0mm | 0.48 | 0.44 | - | - |
| 4.1mm | - | - | 0.72 | - |
| 4.3mm | - | - | - | 0.14 |
| 4.5mm | 0.72 | 0.69 | - | - |
They add. Anything from 0.02 grams to 1.58, in steps as small as two hundredths.
Every combination, worked out. There are close to 600 of them, so they live where there is room for the tables. The Stone Stack on From the Bench has the full additive weight charts for both slotted and round, plus a hook-by-hook chart of which Tear Drop fits which Firehole Stick.
Three places to start
Small mayfly nymph, #16 to #18. 0.20 g.
2.5mm round Stone and a 2.0mm Tear Drop. Gets down in a foot of riffle without dragging.
Standard jig nymph, #12 to #14. 0.54 g.
3.0mm slotted Stone, 2.7mm Tear Drop, 2.9mm Bug Band. The one most people tie the most of.
Point fly, #10 to #12. 0.73 g.
3.5mm slotted Stone and a 3.2mm Tear Drop. Anchors the rig.
What fits what
Slotted Stones for jig hooks and heavy streamer hooks, round for standard nymph and curved scud and pupa hooks. Tear Drops come in six sizes and not every size clears every hook. Below 2.0mm you are into bead-only territory, and the 419 is a light wire dry fly hook that should not carry a tungsten body in any size.
The hook-by-hook fit chart covers all twenty-eight Firehole Sticks. For which bead size suits which hook size, that is a separate question with its own chart.