First Post from Newbie

I have a small hobby anodizing line set up in the basement, 12-24VDC@2-5A.

I would like to do some "Type III" anodizing, 48-70VDC.

My power supply is a battery charger and two 12V marine batteries. My control is a variable 350W resistor.

Rather than buy 2-3 more batteries, I think that I would like to use a voltage multipling resistor network. I remember seeing plans years ago, always with the warning of how high the voltage could get with these networks. I have also seen commercially produced (cheap) multiplier circuits for small ozone generators (KV) that plug into a autos cigarette lighter socket.

For the life of me, I can't find plans anywhere for a voltage multipling resistor network. Does anyone know of plans, theory, or a reasonable alternative that might give me 2-5 A?

Thanks,

Jim Herbert

 

He might be thinking of a Marx Generator, that uses a bunch of resistors and would generate plenty of ozone!

Not something you would want to use for anodizing, though.

 

Thanks for your input Bertus.

I currently run 16 ASF so an increase to 24 ASF would not be too large, considering the size of my very small tank. I usally run about 2A with both racks full, 18-20 in2. 3-4 A (50Amp Meter) should be tops (for this tank).

Perhaps you are right about the resistor network. Maybe I was thinking about AC doublers,triplers,and so on. It just sticks in this old brain, I know I have tried unsuccessfully to find them before.

I guess its time to either buy some batteries or start digging out old large transformers and caps that have been heretofor classified as boat anchors.

Thanks again,

Jim

Just because the phone net manager gave be the Novice Test 1 day late (31 days after code test) 30 years ago doesn't mean I dislike all Amatures.

When your in a little sailboat in the middle of a large ocean you still reach for the SSB, or the QRP CW Rig (Heathkit w/ VFO.

 

Have you considered using a AC variac transformer wired to a full wave bridge rectifier. It might be the simplest approch as long as you have the means to measure and monitor the output voltage and current. The main advantage is that there would be no waste heat generation and a decent savings on your monthly electric bill.

Here is a typical 10 amp output Variac:

http://www.allelectronics.com/make-a-store/item/SC-10M/10-AMP-VARIABLE-TRANSFORMER/-/1.html

Here is a typical diode bridge rectifier module:

http://www.allelectronics.com/make-a-store/item/FWB-254/25-A-400-PIV-BRIDGE-RECTIFIER/-/1.html


Lefty

 

Thanks Lefty,

The variac looks very nice. Is it an autotransformer? I started getting shocks from a large surplus variable autotransformer that I used to use as a power supply, and junked it long ago.

The variac my be a nice ultimate solution if I continue to due Type III anodizing but I think that it is a little too expensive for me right now.

Nice bridge.

Thanks Again,

Jim

 

Lefty,

Yes, a Variac is an autotransformer. I just bought one from the surplus place, 10A $54, no enclosure. I hope I don't light up the anodizing bath like I did the plating bath years ago, a short means line voltage in the tank.

I am not too concerned about power supply voltage regulation but any circuit ideas for current regulation?

Jim