Looking for electro etch plans

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I already heard back from the engineer.
Basically, there aren't any affordable improvements to make to this machine.
Here is his explanation
The run-away voltage "is probably due to the fact that your supply is unregulated and probably has a fairly high output impedance (i.e. as the load goes up, the voltage goes down - and visa versa). So, as your anodizing coat gets thicker, and also the resistive solution gets warmer its conductivity increases which reduces the load current on your power supply - and since the supply is not regulated, the voltage goes up."

He said that a capacitor would help my machines performance, but he said it would be expensive and difficult to find the one I need. We didn't discuss that any further and I didn't get a complete explanation.

He suggested means to make a cheap regulated variable power supply. Apparently there are cheap regulated variable power supplies available for around $5 but they only go up to 35 volts. He was calling them "317 chips". Now, 35 volts isn't very useful for anodizing so you would augment this with car batteries run in series. Car batteries are regulated. In this way you could make a regulated variable power supply that could go up as high as you want.

He confirmed that my multi-meter is set up correctly to measure voltage. I have a separate Amp-meter that is run is series, it's the little gauge on the black box. He said that my multi-meter may be damaged if I set it to read amps in it's current orientation. I'll be careful not to do that.
 
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The pieces will draw the amps that they need, although I am electrically dumb so don't take my word for it.

Many Auto alternators are rated at 100 amps or more output but a single light bulb or radio isn't going to use all of that juice, it is just there on demand.

If you start getting into larger surface areas, your setup will use more amps and the variac and other parts will get hotter.
 
I won a variac off of ebay last night and can't wait to get my etcher/anodizer/plater going, I also picked up all the other stuff I'll need according to Bob Warners video "the electrolysis of metalworking".

So, where's a good place to get stencil material and the developer solution?
 
Sorry for the three seperate posts...

After reading more of the posts describing the problem and watching Bob's video, I noticed that Bob only uses his meter to measure voltage as amps are not really important. But what he does is when the voltage flops around when the piece is put in the solution, he adjusts the voltage on the variac to stabilize it.
 
RUGUR said:
the amp-meter will slowly climb over 160V.
Click to expand...

I'm confused now. Is the amp meter measuring V or A? Like your friend said Amps will change through the process. anodizing titanium and judging colors is by voltage, not by amps.
 
Find and old computer and pull the power supplly out of it.
They put out 12 volts to the small fan inside the computer.
Works great.
 
I was just wondering how the Q tip thing works, I thought there had to be a piece of steel wrapped in cloth, you just clip straight to the Q TIP ?
 
12 V will work for an etcher but if you're building an etcher/anodizer, 12 volts won't do you much good.
 
69_Knives-
My multimeter is set to measure Volts. I use the voltage reading to predict what color the titanium will be colored. Monitoring the amps doesn't seem to be very useful. I have a separate amp-meter installed on my project-box. The amps seem to stay very low, around 1amp... unless my meter is broken and I haven't realized it.
You are correct that Mr. Warner used the dial on his variac to control and stabilize the voltage during anodizing. That is what I do as well. I was just hoping that I could find a way to make it easier to control, more stable and predictable. I discovered that there is no affordable way to to improve the control of this machine. It's as good as it is going to get.
There are many ways to make stencils for etching. If you run a search on this forum you will find a bunch of info. There are services that will make stencils for you or you can make them yourself.
About the most simple way to make a stencil is to just paint a spot of nail polish on your steel and then scratch your logo thru the nail polish.
 
Hmm, that sounds like a strange problem indeed. I hope I don't have any anomalies like that when I get mine built.

I may have been more or less mistaken when I said Mr. Warner corrected the voltage while anodizing, I just remembered in the video where one time he did adjust the voltage to be higher for a different color while the piece was in the solution but other than that, the voltage would flip around for a second or two and then stabilize so it makes me think that there may be something faulty with your setup.
 
Incase you didn't follow, the electrical engineer I spoke with said that my machine is behaving normally. So you should probaby expect your machine to behave similarly. It really isn't all that dfficult to control the voltage once you get the hang of it. I may have made it sound a little worse than it really is.
 
Was thinking about putting a Voltmeter and an Ammeter somewhere in the circuitry to better watch what's going on.

However, I'm not sure where to put them nor what the range of the Ammeter should be. I suppose the Voltmeter with a 0-30 vdc should be okay.

I also want to put in a circuit breaker instead of a fuse.

I've got the wiring diagram from here.

Also, look here for the parts list.

My material will be Aluminum T6-6061 so what will the best electrolyte be? Would the salt and vinegar work okay?

Any feedback would be appreciated.

Thanks in advance,
Vogavt
 
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I just built Chris Crawfords etcher, but I found the alternate wiring on the internet and wired it the 12 volt way. Then I ordered some stencils from Ernie, who by the way was very helpful and great to talk to. I love the look of this mark way better than my old stamp.
 
Yeah, I found the 12v diagram at Michael LoGiudice's page and plan to wire it that way but add another selector switch to toggle between 12v/24v. The extra kick should allow me to use it as an Anodizer as well.

After I stumbled upon The Beginner's Guide to Etching, I wanted to add the voltmeter and ammeter gauges.

I also plan on adding a variable resistor/rheostat/potentiometer of the sort to dial in the voltage. Might need some help with that one. I have a couple of EE's I can call upon to look it over first.

I will be doing a CAD drawing of schematic and will post it for review, PRIOR to actually wiring and flipping the switch.
 
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I've added the circuit breaker, voltmeter, ammeter and switch for toggling between 12V and 24V.

BEWARE!! This has not been tested. I only want someone to look at it and help me in determining if it's correct.

I noticed that mlogiudice's version shows the unused tap off of the transformer as being taped off and unused. I Chris Crawford's version it shows the #2 wire from the transformer going to ground.

I've shown this modification as switching between the #1 & #2 wire and putting them to ground when the other is being used.

Not sure if they both couldn't float though instead of being grounded.


Here is the Modified Electro-Etching Unit Schematic version.


Thoughts? Comments? Errors Found?

Let me reiterate:
BEWARE!! This has not been tested. I only want someone to look at it and help me in determining if it's correct.


Thanks in advance,
Vogavt
 
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No! No!

Don't switch the any of the wires on the secondary side of the transformer to ground! This will be an immediate short, and will likely blow the transformer.

The ground on the transformer case means that all of your ground points should connect there, such as the green ground wire from the wall outlet. The transformer case is your ground point.

If you want to switch between 12Volt and 24volt, then simply exchange the #1 tap with the #2 tap shown on your drawing. Don't ground the unused tap off of the transformer.

Mike LoGiudice
 
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