Formvar is a synthetic enamel composed of polyvinyl acetal and phenolic resins.Formvar's hot oil resistance sets it apart from all other magnet wire insulations. The flexibility, adhesion and abrasion scrape resistance of Formvar film is excellent. Its electrical properties are very good and it is resistant to common solvents. While Formvar has been replaced in many applications, Formvar continues to be the recommended film insulation most commonly used in oil-filled transformers.Typical ApplicationsOil-filled transformersMotorsRandom wound coilsSolenoidsGuitar Pickups
For Use in Guitar Pickups Formvar serves as an excellent choice of winding wire for pickup manufacturing companies and is chosen for it's resistance to common solvents (including sweat and other liquids that can find its way into a guitar's pickup). Heavy Formvar is used where top end brightness and note definition are desired, due to fewer windings than with thinner wire with more windings.
| Field | Value |
|---|---|
| UL Listing | UL Recognized Class 105 Product |
| Mil-Spec No. | MW 15-C/A |
| AWG Size | 9 |
| Min. Bare Wire Diameter | 0.1133 in |
| 2.878 mm | |
| Nom. Bare Wire Diameter | 0.1144 in |
| 2.906 mm | |
| Max. Bare Wire Diameter | 0.1150 in |
| 2.921 mm | |
| Min. Increase in Diameter Due to Film Coating | 0.0032 in |
| 0.081 mm | |
| Min. Overall Diameter of Film-Coated Wire | 0.1165 in |
| 2.959 mm | |
| Max. Overall Diameter of Film-Coated Wire | 0.1189 in |
| 3.020 mm |