Re: gEDA-user: PCM making methods - was - Re: alarm clock update
Do you have any links about CuCl? This looks very interesting, so I did a bit of googling and these links seems to deal with most aspects: http://www.xertech.net/Tech/CuCl_ech.html http://members.optusnet.com.au/~eseychell/PCB/etching_CuCl/index.html ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: PCM making methods - was - Re: alarm clock update
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Daniel Sandström wrote: Do you have any links about CuCl? This looks very interesting, so I did a bit of googling and these links seems to deal with most aspects: http://www.xertech.net/Tech/CuCl_ech.html http://members.optusnet.com.au/~eseychell/PCB/etching_CuCl/index.html The first one only contains BW pictures, so the second one is much better, as color matters :) Thanks - - C. Lechner -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.7 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFG6BNDWo2QgtqY4K8RAp0oAJ0XNYeafP4qjcbhqj4ZMFpaBGorkQCfQ5WY 4PLrWCoRZSkvPbEuDo2y+G0= =CH+h -END PGP SIGNATURE- ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: PCM making methods - was - Re: alarm clock update
Christoph Lechner wrote: So you simply mix a HCl/H2O2 etchant the usual way. When you begin to use the etchant, it's bluish. No. Yellow-green for full etching strength. After some time (and some PCBs) it becomes green. Dark green, and when loaded with copper, black. So when it's green it's CuCl etchant, isn't it??? Pretty much. John G -- Ecosensory Austin TX ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: PCM making methods - was - Re: alarm clock update
Here are some photos of H2O2/CuCl2/HCl in action at 105 degF: http://shop.cottagematic.com/elab/etch-midway-5mins.jpg http://shop.cottagematic.com/elab/etch-done.jpg http://shop.cottagematic.com/elab/etch-tank-depleted-sm.jpg John G Daniel Sandström wrote: http://members.optusnet.com.au/~eseychell/PCB/etching_CuCl/index.html The first one only contains BW pictures, so the second one is much better, as color matters :) -- Ecosensory Austin TX tinyOS devel on: ubuntu Linux; tinyOS v2.0.2; telosb ecosens1 ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: PCM making methods - was - Re: alarm clock update
Daniel Sandström wrote:
http://members.optusnet.com.au/~eseychell/PCB/etching_CuCl/index.html
The first one only contains BW pictures, so the second one is much
better, as color matters :)
from etching_CuCl/index.html:
the solution effectively just grows as it consumes four ingredients during its
lifetime.
These include; copper metal, oxygen (from air), hydrochloric acid, and water.
The
overall equation during regeneration can be written as;
[4] 2HCl {aq} + 2CuCl {aq} + O {aq} → 2CuCl2 {aq} + H2O{aq}
So this solution does grow some from balancing by adding acid,
and by H2o production during regeneration... The disposal methods are
going to be the same as with H2O2...neutralize excess, sell
the copper oxide sediment.
Hmm recommend optimum specific gravity to be between 1.240 to 1.330
I wonder if the wine gravity gauge I have has that range
Here's a big consideration: graph demonstrates that when more than
approximately
5 g/l of copper is dissolved in solution and is not regenerated, the etch rate
begins to decrease, and becomes almost zero when monovalent copper reaches
20g/l.
That means bubbling as you go, or all stop... The write up shows a photo that
is
about like you get in phases of a H2O2 bath (with no titration required -- all
the time)
http://members.optusnet.com.au/~eseychell/PCB/etching_CuCl/cucl_colors2.jpg
is the range of colors of a H2O2 bath, yellow green being lots of H2O2, close
to too much
where HCl bubbles out (undesirable -- avoid that). The write up says dark
green is still
good for fast etching, so waiting till blackish green is OK, then add H2O2
until mid green will
avoid fuming.
H2O2 is a valuable aid to the method of making a bath. I found the high
strength kind (35%) at
a hydroponics supply place of all things...at a good price of US$ 9 per liter
made by Grotek
in Canada.
John Griessen
--
Ecosensory Austin TX
1
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Re: gEDA-user: PCM making methods - was - Re: alarm clock update
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 John Griessen wrote: Hmm recommend optimum specific gravity to be between 1.240 to 1.330 I wonder if the wine gravity gauge I have has that range AFAIK the density of ethanol is below 1g/cm^3 :) I'd prefer a hydrometer as used when measuring the density of the acid in car batteries. IMHO the ideal density value of the sulfuric acid/water mixture in the car battery is in the range of 1.3g/cm^3: A fully charged car battery has an electrolyte density of 1.28g/cm^3, while a completely discharged car battery has one of about 1.1g/cm^3. - - C. Lechner -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.7 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFG6FypWo2QgtqY4K8RAoVsAKCRh+dmLpagjPLQhdb0qmqtP5NrdACcD9/5 mngn2+I6kHGs1K7mF/hj8kg= =5rjG -END PGP SIGNATURE- ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: PCM making methods - was - Re: alarm clock update
DJ Delorie wrote: laser cutter seem like a prudent investment :D More like $90k. I've checked. I have some old experience with lasers and a YAG laser with no practical pump. If anyone sees some 807-nm laser diodes that output a line of light, or are coupled to a fiber, tell me. I can use them to pump the Nd:YAG 5 inch long rod of my 60 Watt formerly lamp pumped basket case laser. HCl/H2H2 (and the CuCl I use) do not give as sharp an edge as FeCl3. I'm liking the transparency and low hassle and low toxicity of HCl/H2O2, and mostly want to do prototypes or circutis that go on low cost substrates so don't need to be teeny as possible to save board area. I like the low tolerance approach -- don't want to be a commercial fab. I got pretty good results etching DJ's lines test pattern for choosing amount of bloat to use in making postscript masks. 8 or 9 mils was the limit with my laser printer and toner transfer. I didn't see much morphing of shapes from etching. I etched with good stirring action. My HCl/H2O2 recipe is: 250 ml 35% Hcl, 35% H2O2 500ml distilled water, do all the acid precautions, work under a shade tree, use 1000ml Erlenmeyer flask, add half the acid to the water, stir and add the rest slowly, heat on hot plate to 105 deg C, add 3 5 inch lengths 12 Ga Cu wire, stir occasionally till dissolved, Next add 20 ml of H2O2 and 40ml of HCl at a time according to appearance. Aim for yellow green solution, if blueish needs more HCl, add H2O2 carefully, and if you see bubbles starting to evolve much, stand back since it's chlorine. Now to use for etching, just observe colors: If dark and starting to be hard to see your board from too much dissolved copper, add some H2O2 to clarify. If getting to be forest green or blue green, it needs more HCl. The solution volume grows. Neutralizing with Na-OH gives copper oxide precipitate and fairly pure slightly salty water you can dump on the ground. That's what I like about it compared to FeCl. No bright orange stains (on everything), and easier to neutralize and the remains of neutralizing can be sold even. The problem with brass is that it's *thick*. This is maybe the root of why pros use a laser for stencil making. Optimum stencils even need thickness variations across them done by etching zones before cutting. What would vary thickness zones of plastic stencil media before cutting? John Griessen -- Ecosensory Austin TX ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: PCM making methods - was - Re: alarm clock update
John Griessen wrote: work under a shade tree, use 1000ml Erlenmeyer flask, add half the acid to the water, stir and add the rest slowly, heat on hot plate to 105 deg C, Should read 105 deg F JG -- Ecosensory Austin TX tinyOS devel on: ubuntu Linux; tinyOS v2.0.2; telosb ecosens1 ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: PCM making methods - was - Re: alarm clock update
I have some old experience with lasers and a YAG laser with no practical pump. If anyone sees some 807-nm laser diodes that output a line of light, or are coupled to a fiber, tell me. I can use them to pump the Nd:YAG 5 inch long rod of my 60 Watt formerly lamp pumped basket case laser. I'll check to see if we have any lasers using that wavelength at work. Can you use other wavelength? I'm sure to find some 1330's around. gene ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: PCM making methods - was - Re: alarm clock update
John Griessen wrote: I'm liking the transparency and low hassle and low toxicity of HCl/H2O2, and mostly want to do prototypes or circutis that go on low cost substrates so don't need to be teeny as possible to save board area. I like the low tolerance approach -- don't want to be a commercial fab. I got pretty good results etching DJ's lines test pattern for choosing amount of bloat to use in making postscript masks. 8 or 9 mils was the limit with my laser printer and toner transfer. I didn't see much morphing of shapes from etching. I etched with good stirring action. My HCl/H2O2 recipe is: 250 ml 35% Hcl, 35% H2O2 500ml distilled water, do all the acid precautions, work under a shade tree, use 1000ml Erlenmeyer flask, add half the acid to the water, stir and add the rest slowly, heat on hot plate to 105 deg C, add 3 5 inch lengths 12 Ga Cu wire, stir occasionally till dissolved, Next add 20 ml of H2O2 and 40ml of HCl at a time according to appearance. Aim for yellow green solution, if blueish needs more HCl, add H2O2 carefully, and if you see bubbles starting to evolve much, stand back since it's chlorine. Now to use for etching, just observe colors: If dark and starting to be hard to see your board from too much dissolved copper, add some H2O2 to clarify. If getting to be forest green or blue green, it needs more HCl. The solution volume grows. Neutralizing with Na-OH gives copper oxide precipitate and fairly pure slightly salty water you can dump on the ground. That's what I like about it compared to FeCl. No bright orange stains (on everything), and easier to neutralize and the remains of neutralizing can be sold even. If you let the HCl H2O2 just keep going to emerald green you will get CuCl etchant. You never again need to add H2O2 and can regenrate it by bubbling air through it. I have been using CuCl for a bit over a year now and all I ever need to do is measure the acid levels and density and then top up with HCl or water to keep it in spec. Will still stain like FeCl, but you never need to neutralise it or throw anything away. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
gEDA-user: PCM making methods - was - Re: alarm clock update
JohnG wrote: What do you all think about inkjetting of resists? The second biggest problem apparent with direct inkjet is pooling. The big problem is surely the ink not actually resisting. But pooling caused by too much ink in one spot while wet is causing uneven coverage and the thin areas wash away or crack. Filling all the carts with one colour and printing composite black will prob make that worse. Maybe one solution is to hack the printer or rewrite the driver to do single pixel bands with a few seconds between each pass to allow ink to dry. I never looked into it too much as I didnt find the other methods of making a PCB too painful. DJ Delorie wrote: In my case, since I was etching brass, I probably could have just run the brass through an unmodified printer. But getting the right inks and keeping the nozzles clean seems to be a tricky bit for them. Heck, I have a hard time keeping the nozzles clean with the original inks. DJ - When you are etching your brass stencils they are almost all resist and only tiny apatures. If you work out the cost of inkjet ink and the amount of coverage you need - it may make a $200K laser cutter seem like a prudent investment :D What I'm contemplating is switching to photoresist. You print the pattern on transparencies, photoexpose, develop, and etch. No laminating, soaking, etc. The advantage is that it's easy to line up transparencies because you can see through them, so doing double sided PCBs (or in this case, etch brass from both sides) is easier. YAY - another convert to photo :D. To be honest I have just bought some inkjet paper to re-try the toner transfer option. I was doing it 10-15 years ago using OHTs. The trannys gave beautiful results but where temperamental. The photo paper is quite reasonable in terms of quality and I may use it from time to time on single sided baords with 16/16 rules. I am going to stick to photo for the DS 6/6 stuff though. I might switch etchants to something see-through too, like the HCl/H2O2 mix. HCl/H2H2 (and the CuCl I use) do not give as sharp an edge as FeCl3. Also I think for your brass masks that HCl may not be the best solution. Check with someone smarter than me, but I think it is bad with brass. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: PCM making methods - was - Re: alarm clock update
andrewm wrote: DJ - When you are etching your brass stencils they are almost all resist and only tiny apatures. If you work out the cost of inkjet ink and the amount of coverage you need - it may make a $200K laser cutter seem like a prudent investment :D DJ Delorie wrote: SNIP But I use a laser *printer* not a laser *cutter*. Printing a page of mostly-black isn't that expensive. Yep - full coverage pages on a laser printer only work out $1 as opposed to inkies that are $5ish. The photo paper is quite reasonable in terms of quality and I may use it from time to time on single sided baords with 16/16 rules. I do 8/8 with TT but them I'm using the special paper that releases easily. I have inquired with pulsar about prices as I may start selling it on my web shop. If I get a reasonable response I may have a few 100 boxes of it sitting here soon. The test board I did with the generic inkjet photo paper was the 8/8 rule IR-RX I have posted pics of. The 8/8 rules came out OK in about 5 of the 12 PCBs on the panel. And the PCBs are only 8x14mm. So I think the chances of getting a large board working at 6/6 is pretty slim. I know I can do this easy with photo and FeCl (though not with CuCl) I am going to stick to photo for the DS 6/6 stuff though. The limiting factor (for me) for the TT is the quality of the edges. I haven't tried disableing REt though, it might be dithering the edges for me. Look at these photos. It is of a spiral/swirl test patter someone on homebrew PCB made up (Derrik maybe). http://www.thehacktory.com/LaserWide.jpg http://www.thehacktory.com/LaserClose.jpg It shows some macro shots of some lines that are somewhere between 4 and 6 thou. This shows how the toner particles scatter and make a fuzzy edge as opposed to a nice clean line. That is going to limit your res no matter what method you use a laser printer for (photo or transfer). The printout in the photo above was on a medium sized car priced laser printer. The little $2000 printer I have on my desk does worse than this. I assume that cheaper 1200dpi printers are even worse again. My old HP-LJ4 that was only 600dpi didnt suffer as much. I guess the toner particles where bigger and more controlable I think to get better resolution I should resurect my much stalled plotter project :( SNIP ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: PCM making methods - was - Re: alarm clock update
http://www.thehacktory.com/LaserClose.jpg Yup, that's the kind of fuzzy I get (but more so). However, with properly humidified TT paper, I do get a more consistent black than that photo. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
