diy pcb materials - Page 5 - diyAudio
Go Back   Home > Forums > Design & Build > Construction Tips

Construction Tips Construction techniques and tips

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 7th April 2013, 01:18 AM   #41
diyAudio Member
 
Join Date: Jun 2011
Quote:
Originally Posted by iaxxaxxai View Post
For some very simple designs, you can hand etch it with a rotary tool and a scribing tip of some kind. I'm working on a power supply cap board right now that I'm doing that way. Much less hassle than chemical etching when there's really not much copper that needs removed.
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.

Click the image to open in full size.

...a 'hand-etched' variation on dead-bug at ~ 1MHz IIRC.
__________________
Now I am Become Death, the Destroyer of Words

Last edited by counter culture; 7th April 2013 at 01:21 AM.
  Reply With Quote
Old 7th April 2013, 01:42 AM   #42
diyAudio Member
 
sofaspud's Avatar
 
Join Date: Nov 2005
Location: San Antonio
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.
__________________
It is error only, and not truth, that shrinks from enquiry. - Thomas Paine
  Reply With Quote
Old 7th April 2013, 02:26 AM   #43
diyAudio Member
 
Join Date: Jun 2012
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.
  Reply With Quote
Old 7th April 2013, 02:34 AM   #44
diyAudio Member
 
Join Date: Mar 2013
Location: Indianapolis
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.
  Reply With Quote
Old 7th April 2013, 05:34 AM   #45
JMFahey is offline JMFahey  Argentina
diyAudio Member
 
JMFahey's Avatar
 
Join Date: Mar 2009
Location: Buenos Aires - Argentina
Quote:
Originally Posted by Dan Moos View Post
@JMFahey: So I assume that's one channel per board in those photos, yes? And the PSU is on the same board? This is one area that keeps amazing me.

With a tube guitar amp, to me the schematic always looks way simpler than the built product. With solid state, I look at a schematic, and can't believe how "clean" its pcb looks!

I hope I can get boards as least as good looking as yours. Tell me about this home made solder flux.
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:

Click the image to open in full size.

which is the muscle of my "Soldanish" DB7

Click the image to open in full size.

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.
  Reply With Quote
Old 7th April 2013, 06:51 AM   #46
diyAudio Member
 
Join Date: Jun 2012
Quote:
Originally Posted by iaxxaxxai View Post
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.
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.
  Reply With Quote
Old 7th April 2013, 10:07 AM   #47
godfrey is offline godfrey  South Africa
diyAudio Member
 
Join Date: Nov 2009
Location: Cape Town
Quote:
Originally Posted by Dan Moos View Post
Would a cheap tupperware or rubbermade food type plastic container work ok?
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]
  Reply With Quote
Old 7th April 2013, 06:21 PM   #48
rephil is offline rephil  Europe
diyAudio Member
 
Join Date: Nov 2004
Location: In Belgium at the French border.
Quote:
Originally Posted by counter culture View Post
Oh, there are multiple types of etchant.

Ferric chloride or ammonium persulphide or muriatic (hydrochloric) acid (spirits of salt) + hydrogen peroxide. The last is handy, because you can get the ingredients pretty much anywhere, whereas the first 2 need to be obtained from a specialist supplier.
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
  Reply With Quote
Old 7th April 2013, 07:44 PM   #49
Art M is offline Art M  United States
diyAudio Member
 
Join Date: Oct 2010
Location: SF Bay Area
Default 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
  Reply With Quote
Old 7th April 2013, 09:22 PM   #50
diyAudio Member
 
Join Date: Jun 2011
Copper carbonate is insoluble in water as far as I know (as far as anything is totally insoluble), so should be OK to throw in the bin, but I'm prepared to hear different if anybody knows different.
__________________
Now I am Become Death, the Destroyer of Words
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
FS: Tech-DIY Impasse preamp PCB, Maida PS PCB mattattnet Swap Meet 2 5th March 2013 09:56 AM
Ultimate DIY cabinet materials? VvvvvV Multi-Way 63 1st March 2010 08:05 PM
Diy from scratch or with readycut materials? lurer Multi-Way 8 9th July 2007 06:09 AM
The sonic character of different PCB materials (or P2P) Bricolo Parts 5 30th January 2004 05:21 AM
pcb materials mrfeedback Solid State 3 8th April 2002 11:02 AM


New To Site? Need Help?

All times are GMT. The time now is 03:31 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2