“Cold start” (also called a reverse dab) is a dabbing technique used with a quartz banger and a dab rig, where concentrate is loaded into the banger before it’s heated, rather than heating the banger first and dropping concentrate in after. It’s popular because it gives more consistent low-temperature flavor without needing an infrared thermometer to judge when the banger has cooled to the right temperature. This is a technique guide, not a product roundup — dab-rig hardware falls in the same restricted category as tobacco accessories on this site, so we’re covering how the method works rather than recommending specific gear to buy.
How cold-start dabbing works
- Start cold. Make sure the banger is fully cooled and clean before loading anything into it.
- Load first. Place a small, pea-sized amount of concentrate into the bottom of the cold banger using a dab tool.
- Cap it. Place a carb cap over the banger before applying any heat — this traps airflow and lets you control vapor density once heat is applied.
- Heat from outside, slowly. Apply a torch at roughly half power, a few inches from the outside of the banger, heating it gradually rather than blasting it.
- Watch, don’t guess. Once the concentrate begins to bubble, that’s the signal to start inhaling slowly — there’s no thermometer step required.
- Adjust as you go. Rotating or slightly lifting the carb cap during the draw manages airflow and vapor density in real time.
Why people prefer it over a traditional hot dab
A traditional (“hot start”) dab heats the empty banger first, then drops concentrate onto an already-hot surface — which makes timing the ideal temperature harder to judge without a thermometer, and easy to overshoot into a harsh, combusted hit. Cold start avoids that guesswork: because the concentrate goes in before any heat is applied, the banger’s actual temperature during vaporization is inherently lower and more gradual, which tends to preserve more of the terpene flavor.
Key technique notes
- Use less concentrate than you think. A pea-sized dab is enough; too much will pool in the bottom and burn unevenly rather than vaporizing cleanly.
- The banger should never glow. If it starts to glow during heating, that’s a sign you’ve overheated it into essentially a hot-start dab done in the wrong order — back off the torch.
- Clean while it’s still warm. After finishing, let the banger cool slightly, then wipe any remaining residue with a cotton swab while it’s still a little warm — this keeps flavor from carrying over into the next session and extends the banger’s usable life.
A note on legality
Cannabis concentrate laws vary significantly by state and country. Dab-rig hardware itself is generally legal to purchase and own in most of the U.S. as drug paraphernalia laws vary by state, but what you use it with is governed by your local cannabis laws — check your state’s rules before assuming legality.