Gabourie, below are the volts/amps per square inch that I use:
Acid Copper: 1.50V @ 85ma. per square inch.
Bright Nickel : 2.25V @ 85ma. per square inch.
I always ramp up the voltage during the first few minutes of plating to insure the metal plates quickly verse oxidizing in the solution.
(really important when nickel striking steel parts)
Nickel:
1st min. 3.0V
2nd min. 2.75V
3rd min. 2.50V
Then at the 4th min. mark it gets set at 2.25V
Acid Copper:
1st min. 2.0V
2nd min. 1.75V
Then at the 3 min. mark it gets set at 1.5V
I have a "Lab" type power supply (0-18Vdc, 0-10A) and using the settings above always gives me perfect results.
I have never buffed any of my nickel plated parts when they come out of the baths. They always look like a mirror.
OK, now this ought to shake everyone up.
All this worry about the "exact" amps per square inch.
I set my supply to the voltages listed above and let the part draw whatever it wants.
Always seems to draw right at 85ma. per square inch.
I have never set the current limit on the supply to match the part size, ever!
Another note: all my solutions are at least (3) years old.
I always filter them with plain old large paper coffee filters after about (10) hours of use.
I have never had to throw out or screw with the solutions, ever!
More shocking news: :
After washing large parts with "Dawn" dishwashing soap (you know...the blue stuff in the squirt bottle) or ultrasonic cleaning the smaller parts (using "Sunlite" automatic dishwasher detergent in the ultrasonic) and a tap water rinse, all parts (steel, copper, nickel, brass...does not matter) get a (1) minute dip in "Nickel Pickle" (battery acid diluted as per Caswell's instructions) then into a tap water rinse tank for (30) seconds and go "Hot" (electrically connected) right into the baths for a minimum (1) hour plate.
Ok, everyone can get up off of the floor...Yes I did say (and use) plain old Florida tap water for rinsing.
I use my roto-plater setup (rotates the parts in the bath) and use LARGE air bubble agitation and always (2) anodes on either side of the tank.
All my anodes are 4" x 6" (or 2 x 12 for horizontal plating, no rotation, air and pump circulation) and are always at least 2" or more (more is better) away from the part. Of course the rotation insures the parts do not "see" the anodes on any high spot for too long (rotates at 24rpm).
Use 2 gallon tanks (I only do smaller stuff)
George W.