Sometimes called Rectifiers or Power Supplies
Rectifiers are simply a source of power or electricity. Their main purpose is to take the 117 volt AC electrical current that we get from our household outlets and convert it to DC. In this country, our electricity comes over the power lines at 117 volts, 60 cycles AC or alternating current that changes direction 60 times a second, while DC or direct current flows in one direction. If we used AC current when plating, we would deposit metal on a surface and take it off 60 times a second. That's the reason for using a DC current.
When purchasing a rectifier most people
have a tendency to buy too large of a unit. This is more evident in brush
plating. Some companies will sell you a larger machine with the idea that if you
want to plate large grills and bumpers you need a higher power machine. This
would hold true only in tank plating where the settings are made according to
the size of the work piece. In brush plating no matter what size the work piece
is, you are only plating approximately two to three square inches at a
time. ( The actual size of the anode on the end of your plating wand.) We do
make larger machines but they are only used for tank plating of large items like
wheels etc. They are not necessary for brush plating.
When you have too much power in a rectifier it is hard to control the lower end of the scale where most of the plating is done. This is especially true in electroforming. In our list of products you will see a Fine Tuner mentioned. This was designed to be used with larger rectifiers or plating machines that are not controllable in the lower end of the scale. With the rectifiers that Dalmar makes you will only need to purchase a Fine Tuner for our 20 and 50 amp rectifiers, the reason being that the scale on the meters can not be broken down in small enough increments.
Some companies claim that all machines are the same and will sell you a machine that has a fixed voltage saying that "the amperage is set automatically" or "it is a automatic machine. We make over 50 chemicals and each require a different voltage or amperage setting. Only a machine that can be set or adjusted to match these different voltages and amperage can make use of all of these chemicals and do the many jobs in plating that come along. If you want to do all types of plating make sure that the machine that you buy has both a voltage and an amperage meter and make sure that the voltage is adjustable. It is like having a one speed motor on a car or a lawn mower. It works fine, but would you want just one speed in your car? I don't think so.
I have seen people try to plate using everything from battery chargers to 12 volt power supplies for running car audio systems. One of our competitors recommend putting a series of light bulbs to control the current, then adding or subtracting the amount of bulbs to adjust the voltage. I have a saying that "this system must have been made in Orlando, FL, because it sounds kind of Mickey Mouse to me". They may work for one or two things but they will never do the whole job in plating. The same with the so called automatic machines. They are nothing more than fixed voltage power supplies. Funny but most of them have one thing in common. They all run at 12 volts. How would you use that for a chemical that calls for 3 volts or to be run at 1/10 of an amp per square inch. Do yourself a favor and buy a proper machine that was designed for plating. you will have less headaches and it will cost you less in the long run in time, money and the frustration of doing a bad job. Also trying to plate off a battery source sounds good until you realize that as the power of the battery goes down, so does your power setting.
Two other styles of machines that I find are useless are the machines that are built into a seat and machines that are built into a box that also stores your chemicals. The machines that are built into a seat have the problem that when you want to adjust the power setting, you have to look between your legs to try to see the machine and everything is upside down including the meters. It is like standing on your head and trying to operate the machine and do your plating. The machines that are mounted in a tool box and has the chemicals stored in the same box, give you many problems. One is that you will splash chemicals on your machine and ruin it through corrosion, and even if you are extremely neat and careful, the fumes from the chemicals will corrode the connections in the machine.
Remember you are working with a rectifier that is a electrical object with many electronic parts and solder joints. You are also working with chemicals, mostly acid base and the two don't mix. Stop and think what happens to a battery when the terminals get corroded, your car doesn't start. That is the reason car manufacturers started to make sealed batteries, to prevent the acid fumes from corroding your electrical system in your car. I have rewired many machines made by other companies, that are made in cases that also hold the chemicals for our customers because they bought that type of rectifier. You have a big investment in your plating equipment, why would you want to buy a piece of equipment that won't last?
The best way if you want that type of system is to buy a rectifier that is in it's own case and purchase a stool type of creeper to sit on, you can also purchase a plastic tool box to carry your chemicals in.
Amp meters on rectifiers will not have a reading unless you are plating something. Sometimes the reading is so low that you will think it is not working. You can test this in tank plating by plating something in copper and turning up the dial for a second or two. In brush plating you can test the rectifier by momentarily touching the black lead to the metal on a wand or pen plater.
Click Here to see models and prices of Dalmar Rectifiers