Rosin, No Clean, Rosin Mildy Activated, Rosin Activated, Water Soluble
Flux removes surface oxides, grit, and grime from metal surfaces, thus improving the quality of intermetallic bonds. Flux is a component coupled with solder bar or solder wire which cleanses and primes a metal surface before soldering.
RO stands for rosin, the L is for low activity and the number 0 is for no detectable halides. a halide-free, rosin-based solder paste with low activity is categorized as ROL0
Flux lowers surface tension which allows uniform solder flow.
Rosin Solder Flux
Rosin (R) flux is a combination of rosin and solvent best suited for clean and easy-to-solder surfaces. Rosin is hard, not conductive, and general corrosion-resistant. Rosin flux residuals may be left on the assembly or removed with a compatible solvent.
- Large wires
- Only clean and easy-to-solder surfaces
No Clean Solder Flux
No Clean (NC) flux combines rosin, solvent, and a chemical activator. NC flux is best suited for easily soldered surfaces. Activity is low-to-moderate and compatible with many assembly types. The clear, hard residue is not conductive or corrosive. Residue removal is achievable with a compatible solvent but more difficult than RMA fluxes.
- Most PCB work
- Designed to be left on many assemblies
- More difficult to remove than RMA fluxes
Rosin Mildly Activated Solder Flux (RMA)
Rosin mildly activated (RMA) flux consists of rosin, solvent and a small amount of activator. RMA flux is often low-activity and best matched with easily solderable surfaces. The clear, soft material is often non-corrosive and nonconductive. Cleaning depends on the flux activity and the product in question for the selection of the appropriate solvent.
Rosin Activated Solder Flux (RA)
Rosin activated (RA) flux combines rosin, solvent, and aggressive activators. Activity is higher than RMA for use on oxidized surfaces. RA flux is corrosive so sensitive assemblies must be cleaned as soon as possible with a compatible solvent or risk damage to electrically conductive performance.
- Best for oxidized surfaces
- Clean as soon as possible after assembly
Water soluble (WS) flux combines organic acids, thixotrope, and solvent. WS flux activity levels vary, from no activity to very high activity. Ideal for soldering difficult surfaces including stainless steel. Reference the product specification for corrosion and electrical conductivity hazards. WS soldering classifications include L, M, and H activity levels and with a halide content of either 0 or 1. Remove residue with water.
- Soldering difficult surfaces, such as stainless steel
- Must consider corrosion and electrical conductivity hazards.
Flux Types and Activity Levels
Flux type:
• RO: Rosin
• OR: Water soluble
Activity level:
• Low: L
• Medium: M
• High: H
Halides detectable
- No: 0
- Yes: 1
ROL0 – “RO stands for rosin, the L is for low activity and the number 0 is for no detectable halides. a halide-free, rosin-based solder paste with low activity is categorized as ROL0”
Solder, Flux & Consumables
PAC is an authorized distributor for AIM and Kester soldering paste, solder bar, and flux products.
Shop gotopac.com or call for help from a PAC soldering and dispensing specialist.
