Rayon Wick – What is it in Vaping?

Definition

Rayon wick is a cellulose-based wicking material made from processed wood-pulp fibres, widely used in RDA, RTA and RDTA coils to transport e-liquid to the heating element. Unlike Cotton“>organic cotton, rayon semi-synthetic structure delivers faster capillary action, higher heat tolerance and neutral flavour transmission, making it popular among Australian rebuilders seeking consistent saturation and extended wick life. Rayon’s silky, almost translucent strands are cut to length, fluffed and threaded through coils, where they absorb juice rapidly, resist scorching and reduce the chance of dry hits during Vaping“>chain vaping.

Technical Details

Rayon fibres average 1.5 denier (≈12 µm diameter) and hold up to 400 % of their dry weight in e-liquid thanks to longitudinally grooved micro-structure. Capillary speed is roughly 20 % faster than bleached cotton, allowing lower RTA decks to keep up with high-wattage builds (0.15–0.3 Ω). Thermal degradation begins around 260 °C, giving a 20 °C buffer over cotton before combustion gases appear. Most vapers buy 100 % rayon “cellu-cotton” balls or cord: 3 mm diameter for single-coil RDA, 4 mm for dual, while flat shoelace variants (6 mm × 2 mm) suit Genesis-style RDTA channels. Because rayon shrinks slightly when wet, builders typically use a 0.5 mm tighter wrap than they would with cotton to maintain firm coil contact.

Usage & Tips

Cut a strip, roll gently between fingers to round the edges, twist and pull through the coil—resistance should be firm but movable. Trim tails at 45 ° to deck floor for rapid saturation on squonk. Prime with a few drops, pulse at 20 W to seat, then cool; rayon darkens less, so re-wick when flavour drops rather than by colour. Avoid over-stuffing: thinning the tail ends prevents flooding in refillable tanks. Rayon is chlorine-free and generally safe; however, always dry-burn coils lightly outdoors to remove residual starches before first use.

History & Context

Originally developed for medical swabs in the 1930s, rayon crept into vaping circa 2014 when US forums compared cellu-cotton balls to premium “Japanese cotton.” Aussie builders embraced it for bulk value—500 g pharmacy bags still cost less than a metre of branded vape cotton—and for its clean, neutral taste that lets dessert and tobacco e-liquid notes shine.