Anodizing by constant current denisty
The Current Density Gauge allows the plater to know precisely what the current density is in the tank for optimum anodizing quality.
After hanging the Current Density Gauge on a bus bar, the operator presses the button for an instant digital display of the current density. This allows the operator to set the correct constant amperage on the rectifier for the duration of the anodize cycle.
WHY ANODIZE BY CURRENT DENSITY?
When the surface area of part isn’t known, many anodizers make a guess at the correct voltage and maintain a constant voltage on the tank.
The problem with constant voltage anodizing is that there are many variables that change the voltage: bath temperature, acid concentration, aluminum concentration, the aluminum alloy, and the voltage will change during the cycle because of the resistance of the oxide layer! So its hard to know what the correct voltage should be. If the anodizer get it wrong then problems with “mossy oxides” or inability to seal will result. In addition, as the anodic film builds, the resistance increases and the current density will decay as the anodizing process progresses. This produces an anodic oxide that is less abrasion resistant, and increases the time required to form the necessary oxide thickness.
Products Finishing article on constant voltage vs. constant current anodizing. Article discussing constant voltage vs constant current control.
PRINCIPLE OF OPERATION
This Current Density Gage measures the current applied to an aluminum plate with an area of exactly 1 square foot. The resulting current reading is therefore a direct reading in ASF. (amps per square foot) The device is powered by a 9V battery. Bright digital display is easily visible in dark environments.
The operation is simply pressing the button on the top to start the readout. The dipslay will shut itself off after a short time like 20 seconds. (this can be easily adjusted in the field) This allows the battery to last for years.
THIS PRODUCT IS IN DEVELOPMENT AND WILL BE READY IN EARLY MAY 2025
