Yes, this works well for some dead-bug style jobs, particularly very basic ones. You can just create some 'islands' to anchor the parts to.
An externally hosted image should be here but it was not working when we last tested it.
...a 'hand-etched' variation on dead-bug at ~ 1MHz IIRC.
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Chlorine, of course, doesn't play well with lots of plastic, rubber, or metal. The ferrous etchants will be fine with the Tupperware or Rubbermaid tubs, and the "microwave safe" type should withstand the double-boiler method. I myself would never use water too hot to leave my finger in it.
As an alternative to a bubbler, you could locate a fulcrum underneath the etching container, and have it rock back and forth (but not so violently that the etchant sloshes about). It'd be nice to have a tank that was tall, wide, and thin so the board could be placed vertically, but I have no idea where to source something like that. Except to DIY it.
As an alternative to a bubbler, you could locate a fulcrum underneath the etching container, and have it rock back and forth (but not so violently that the etchant sloshes about). It'd be nice to have a tank that was tall, wide, and thin so the board could be placed vertically, but I have no idea where to source something like that. Except to DIY it.
For a safe, but slow etchant, I have successfully used vinegar (acetic acid), salt (sodium chloride) and peroxide (H2O2). You need strong vinegar, it can be concentrated a little by boiling it slowly to remove some of the water. Try to find sea salt as you want sodium chloride without to many additives.
I hand draw resist using paint touch up pens.
I start with a photocopy of the board, and paste that to the PCB. Then I drill the holes, by hand, using a dremel with a carbide bit. Next I use an eraser shield to hand draw the traces with a paint pen.
I use a plastic sandwich box as a tank. Mix vinegar and peroxide at about 1:1, immerse the board in the solution, then add about a teaspoon of salt, for 300cc, it will fizz.
Slowly agitate the mix with a small paint brush. If the mix is right, the solution becomes slightly blue, and the copper on the board blackens and floats away.
Keep removing the brown debris with a small paintbrush to keep the copper exposed to the etchant.
If the reaction slows down a little more salt and peroxide will speed it up again.
It can take an hour or so, but apart from a strong vinegar smell the chemicals are quite safe and kitchen friendly.
I wouldn't recommend this system for high volume production but for one-offs and prototyping it is convenient.
Please dispose of the spent etchant properly, the resultant solution contains copper compounds.
I hand draw resist using paint touch up pens.
I start with a photocopy of the board, and paste that to the PCB. Then I drill the holes, by hand, using a dremel with a carbide bit. Next I use an eraser shield to hand draw the traces with a paint pen.
I use a plastic sandwich box as a tank. Mix vinegar and peroxide at about 1:1, immerse the board in the solution, then add about a teaspoon of salt, for 300cc, it will fizz.
Slowly agitate the mix with a small paint brush. If the mix is right, the solution becomes slightly blue, and the copper on the board blackens and floats away.
Keep removing the brown debris with a small paintbrush to keep the copper exposed to the etchant.
If the reaction slows down a little more salt and peroxide will speed it up again.
It can take an hour or so, but apart from a strong vinegar smell the chemicals are quite safe and kitchen friendly.
I wouldn't recommend this system for high volume production but for one-offs and prototyping it is convenient.
Please dispose of the spent etchant properly, the resultant solution contains copper compounds.
I had wondered about vinegar. Cool to see that it works for etchant. I actually tried mixing vinegar with peroxide recently to see if it would "boost" it a bit for cleaning purposes. Tried it out on a penny. After a few minutes the penny was shiny... after a little while longer it started looking bad like it was getting eaten.
Thanks
Yes, one very simple 100W/4 ohms channel + +/-40V rails PSU .
It also has +/-15V sources for preamp and 20mA for power LED.
To see one populated and mounted:
An externally hosted image should be here but it was not working when we last tested it.
which is the muscle of my "Soldanish" DB7
An externally hosted image should be here but it was not working when we last tested it.
and yes, it has an output transformer.
Almost forgot: the protective/soldering flux is easily made:
get a clean jam bottle, with tightly closing cap, put there 4 ounces of pine rosin (old Mom and Pop hardware stores should have it) and fill it to 1 inch below top with good (pharmacy grade) ethyl alcohol, which is the least nasty , cover it and let it sit for a couple days until fully dissolved.
You have 5 years worth of solder flux.
If alcohol evaporates and it becomes too thick, add some more.
Some people use paint thinner but for my taste it's too aggressive.
Sometimes for difficult solder jobs (pot cases, ground lugs, some switch or fuse holder) I dip the tip of solder wire in this flux, to help a little.
Guarantees bright shiny solder.
Also if you mount SMT stuff, lightly brush pcb pads with it before soldering.
A little salt is the magic ingredient, it is the ions in the chloride I think. I cant see why it wouldn't work with lemon juice either. Although I haven't tried it.
I used to use ferric chloride in a cheap plastic lunch box with no problems.
More recently I've learned that spent ferric chloride is an environmental hazard, so it's good to hear about some alternatives. ( I used to just flush the spent etchant down the toilet
).On that note, I discovered accidentally that JIK (a common household bleach/disinfectant) etches PCBs. The active ingredient is "sodium hypochlorite 3.5% m/v when packed". I haven't tried using it to intentionally etch PCBs, so don't know how fast it is, but maybe it's worth experimenting with.
[ot]
Back-story:
Someone burgled my house, smashing a window on the way in and cutting his hand badly on the broken glass. He then proceeded to leak blood all over the place before escaping with a substantial bag of loot.
Fortunately (for me), a neighbor spotted him on the way out and called the cops. He was caught and most of the loot retrieved. When I finally got the stuff back, much of it (including my landline phone) was liberally smeared with blood.
No sense throwing away a perfectly good phone, I thought, but it did seem like a good idea to clean off the blood and thoroughly disinfect the thing. I used JIK for the purpose, being careful (I thought) to just swab the outside and not get any inside the phone.
A day or so later I noticed the phone wasn't working anymore. It turned out a small drop of JIK had leaked through the keypad and eaten through a couple of PCB tracks.
[/ot]
Hi counter culture,
I use hydrochloric acid + hydrogen peroxide at room temperature with good results
. The quantity used is what is needed to cover the PCB that is to be etched.At the end, I remain with a solution that I must in some way get away.
I add with great care sodium bicarbonate (found in every super market) as it generates many nasty bubbles. And I get also a nice blue precipitate of CuCO3, in water with NaCl (the salt found in your kitchen) ...
Letting evaporate the small quantity of water there was, I get, after a few days, a small quantity of crystals that I throw away in the bin. As these crystals are no more soluble in water, there are not a problem for the nature :
.I believe that the chemistry involved in the reactions is described as really is. Let me know if I am wrong : I did not study chemistry when I was young.
Best regards
rephil
Short cut
These guys will fix you up with a System to make your own PCB Boards and you can find descriptions of tested procedures for Toner Transfer fabrication.
PCB "Fab-In-A-Box" ... The 8min circuit board system
These guys will fix you up with a System to make your own PCB Boards and you can find descriptions of tested procedures for Toner Transfer fabrication.
PCB "Fab-In-A-Box" ... The 8min circuit board system
Get one of these Dremel 220-01 Rotary Tool Work Station - Amazon.com or one of its countless cheap clones.
Thank you sir,
Since I have no online purchase option at my place, I placed the order to a shop after your this post.
Their first attempt failed. They told me they will try again.
So all I can do is to cross my fingers and wait.
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