Etching at Home

[Stiege]

Currently for me to make a board I print onto Press n Peel PCB film:

http://www.jaycar.co.nz/productView.asp?ID=HG9980&keywords=PCB&form=KEYWORD

Then have to use my iron to transfer this to copper, and etch with ammonium persulphate.

The end result has not been great. The heat transfer is probably the hard part when trying to use an iron to heat what can be a reasonable size board. Can someone suggest some better equipment?

Cheers

[smashedProton]

I etch boards! 

Using dry film is the best way to do it.  If you are not getting good results,  you should try cleaning the surface better, and by putting a high thread count sock over the iron.

Your problem is probably your developer..  The best diy developer is a solution of sodium silicate (water glass) and sodium hydroxide.  Hit up mikeelectricstuff's website for more info.  He has done a wonderful job.

The etchant that I use is ferric chloride.  I know that it is terrible for the environment, but I know how to dispose of it properly.  I make it myself so that i wont be ripped off by anyone.  Take a jug of muriatic acid, and slowly react it with an excess iron in a pyrex container.  Be careful of fumes.  the youtube channel nurdrage has an excellent explaination.  Good luck

[alanb]

I have recently started to etch boards and have achieved good results.

I use photo sensitive boards exposed through tracing paper. Then developed in Sodium Metasillicate and etched in Ferric Chloride.
My light source is a standard low wattage CFL lamp.
 I can strongly recomend reading Mikeselectrical's PCB advice.

[Stiege]

I etch boards! 

Using dry film is the best way to do it.  If you are not getting good results,  you should try cleaning the surface better, and by putting a high thread count sock over the iron.

Your problem is probably your developer..  The best diy developer is a solution of sodium silicate (water glass) and sodium hydroxide.  Hit up mikeelectricstuff's website for more info.  He has done a wonderful job.

The etchant that I use is ferric chloride.  I know that it is terrible for the environment, but I know how to dispose of it properly.  I make it myself so that i wont be ripped off by anyone.  Take a jug of muriatic acid, and slowly react it with an excess iron in a pyrex container.  Be careful of fumes.  the youtube channel nurdrage has an excellent explaination.  Good luck

Sounds great, but with the Press N Peel there's no development required, I just heat transfer, and that seems to be the struggle, and then etch. Should I switch to dry film photo resist and get a UV light?

The etching has gone well, I've used ferric chloride at university but the ammonium persulphate has worked well enough at home and is fine for me starting out with.

I have recently started to etch boards and have achieved good results.

I use photo sensitive boards exposed through tracing paper. Then developed in Sodium Metasillicate and etched in Ferric Chloride.
My light source is a standard low wattage CFL lamp.
 I can strongly recomend reading Mikeselectrical's PCB advice.

Yup, think i know where to go from here. Cheers everyone!

[Alana]

I had problems with press and peeel technique as well until i realized few things.
1. iron needs to be hot enough, at least 160-200 deg celsius and there need to be lots of pressure while pressing. I use small vice to hold my iron, hot surface to the top then i place board on it and printed layout on top. Then i use peace of cloth to apply pressure, literally rub each square cm of the board with considerable amount of pressure. Repeat 2-4 times.
2. press and peel paper i'm using is lined with chalk [CaCO3] and this is prone to acid. If i have a big board or multiple boards at once i soak it in kichen vinegar for some time then peel it off under warm/hot water.
3. board - if its new cleaning it with acetone or nitro laquer solvent is enough, if its older and its oxidized its better to clean it with sand paper, some guys even see sand paper as means of make bard more adhesive for toner used in press-peel mehod but i dont think its always needed.

With practise - in my case 10 boards about 5x7cm i got repetable good results. But still - its wise to have permanent marker that is echant-resistant for small corrections.

[member_xyz]

I have tried blue press n peel from jaycar and gave up due to inconsistently poor results and frustration.

I have experimented a lot with laser ink toner transfer method.  Eventually I found an inexpensive Fuji laser printer <$50, semi glossy paper and a laminator is giving me a much better and more consistent results. Brother laser ink toner is generally not good and you can find a lot of info on the net about ink toner transfer.

Press n peel is expensive and sounds more professional but I could not get good results from it.

Laminator is so much easier to use than iron with right ink toner, but will not work with press n peel.

[Stiege]

I have tried blue press n peel from jaycar and gave up due to inconsistently poor results and frustration.

I have experimented a lot with laser ink toner transfer method.  Eventually I found an inexpensive Fuji laser printer <$50, semi glossy paper and a laminator is giving me a much better and more consistent results. Brother laser ink toner is generally not good and you can find a lot of info on the net about ink toner transfer.

Press n peel is expensive and sounds more professional but I could not get good results from it.

Laminator is so much easier to use than iron with right ink toner, but will not work with press n peel.

Thanks for that, I'll look into laser toner transfer before I splash out on a UV setup.

[Slothie]

I'd +1 on the laminator idea too. While experimenting with the laser printer/photo paper technique I found that if you use an iron its hard to get the pressure right - not enough, it doesnt stick, too much & the toner spreads too much, and with larger boards its hard to get the coverage even. I got some OK results with the laminator using a thin cardboard sheet folded over to "envelope" the board to stop things moving & increase the laminator pressure. I really need to go back and finish my experiments because since then I've changed laser printers and so need to redo all my timings etc!!.

I always lightly rub the laminate with a piece of Scotchbrite in all directions and then buff with a dry cloth to remove residue immediately before doing the toner transfer, Dont make any deep scratches or the toner will melt & run along them...

I found an important factor with ammonium persulphate was to keep it hot! I stand the (plastic) bottle in a bowl of water at about 60 deg C to warm it through, and stand the etching tray in a bowl of water at a similar temp. It etches MUCH faster and you get better edges which makes getting fine detail easier. I imagine the same applies to Ferric Chloride too.

BTW the best photo paper I found  was some no-name stuff I got at the pound shop. The Kodak stuff I tried was almost impervious to water and impossible to soak off - the cheap stuff peeled of after only a few minutes in hot water leaving very little residue behind. I went back and bought all they had in case they never stock it again!!

I've got some projects coming up with SMT so I might revisit this..... 

[Psi]

I have tried blue press n peel from jaycar and gave up due to inconsistently poor results and frustration.

Really?  i've had pretty good success using blue press n peel from jaycar.

- Ya need a printer which can do nice dark blacks.
- Make sure the sheet cant move while you iron it. I make it larger than needed and superglue two corners.
- I put the pcb on a sheet of cork 5mm thick. Then the press n peel blue goes on, then two sheets white paper on top.
- Press with reasonable force on the iron (but not crazy) and vary the force direction (the iron surface wont be perfectly flat)
- When your done keep the iron on the work and switch it off at the wall to wait for it to cool down. If you try and take it off while its hot you'll just smudge it.
- Once it's cool peal the stuff off slowly on a diagonally axis. Roll it off so it only separates one bit at a time.
eg

     --> use finger to roll it off
                 ______
                [__blue sheet_____
----pcb--------------------------

- I use FeCl or HCL+peroxide to etch.

I did try ammonium persulphate once but its no good for press-n-peel.
Ammonium persulphate needs to be VERY hot to work and the heat will make the toner and press-n-peel separate from the pcb during the etch.



I did this TQFP with press n peel blue.
It pushed the stuff a bit far (few breaks that needed pen touchup) but it did work well enough to use.

[nukie]

Toner transfer has been a try and try again for me since day one. The ironing is fine I manage to persuade my wife she needs a new iron so I can 'own' the old one for PCB work. The temperature dial is set permanently, and I always place a piece of cotton on the Pulsar TTS paper in between the iron, I suspect that it helps even out edges. I let the weight of the iron do the work, sometimes I apply a little pressure, too much means squashed tracks no good.

The problem with my printer is in consistency. I can see certain parts of the thin tracks very dark and if there a fill or a thick track these area seems to be light and pitting occurs when I etch. Toner save is off and density is set to darkest ever. It's a windows 2000 era Canon laser printer.

So I might just try the DuPont Riston dry film next time I make a PCB hopefully it will provide good results.

tapatalk

[Moshly]

Hi, I use the pulsar method outlined here -> http://ultrakeet.com.au/write-ups/makepcbs

Apparently you can use the press 'n' peel instead of the transfer paper and green foil. (I haven't tried it) I find that ferric chloride gives the best results (straight edges). Let your laminator heat up for 1/2 hour. I have found large PCB's sink allot of heat and may get too cool by the time the trailing edge gets to the heater. You can try feeding it back again but this causes another problem, the thermal expansion characteristic of the transfer paper and the PCB do not match and the far edge (print) may lift. After you've transferred the toner (using toner transfer paper) make sure all the gum is washed from the board (can cause blotches, green foil sticks to it or it prevents the foil sticking to the toner). I rinse the PCB under warm tap water gently running my finger over the board until my finger starts to grip the toner. After the application of green foil step use masking tape to dab over the board to remove any excess. Make sure your blank PCB is clean of oils, I find cleaning with very fine wet & dry sandpaper and soap & water. Make sure the blank PCB and the print is free of dust when you apply the print.

ExampleBad.jpg : Defects caused by dust, note the pitting (bubbles) using Ammonium Persulphate.

All other pictures etched with Ferric Chloride, the A605 PCB took a long time, fixed a few open/short circuits during the process, after etching i had 3 shorts and 1 open circuit. I think this is probably the limit for home made PCB's, from memory its 6mil/6mil.

Used - Xerox Phaser 3125N & Modified GBC H65

[Stiege]

Thanks, that's some great pr0n. Very impressive.

[JoeyP]

If you have access to a flat-bed plotter, and if your CAD package can output in a format the plotter can use, you can plot the artwork directly onto bare copper. Just etch with ferric chloride and clean with acetone. Plate if desired.

About 25 years ago I started using my Roland DXY990 plotter and got very good repeatable results. Good enough that I made a dozen PCBs for a small run commercial product. Off-the-shelf felt-tipped pens worked fine. I found that the color of the pen made a surprisingly big difference in the result. For some reason, red worked best. You can often buy those Roland plotters on ebay for around $100 or less.

For touch-up, off-the-shelf Sharpy pens used to work very well - better than the expensive touch-up pens available at the time. I don't know if they've changed their chemistry, I haven't made any PCBs at home in years.

[MetraCollector]

Gentlemen, did you heard about alkaline etching ?
It is the main way of etching boards in industry widely spread.

http://www.chemcut.net/downloads/alkaline-etch-process.pdf

I use it at home, my friend gave me some introduction through this article :
http://svetelektro.com/clanky/alkalicke-leptanie-dps-532.html - sorry, slovak language, you can translate it:

http://translate.google.sk/translate?sl=auto&tl=en&js=n&prev=_t&hl=sk&ie=UTF-8&eotf=1&u=http%3A%2F%2Fsvetelektro.com%2Fclanky%2Falkalicke-leptanie-dps-532.html

Good luck, it is very good at home because of non corosive behaviour and all things considered, use of the solution is unlimited.

[GK]

Does anyone still use the UV method? My stock of inkjet transparencies is running out and the stationary warehouse I bought the last batch from doesn't seem to stock them anymore. In fact nobody seems to stock them anymore. Anyone know a reliable source?

EDIT: Never mind, Kalex Electronics is now (finally) selling a suitable alternative product:

http://www.kalexelectronics.com.au/polyester-artwork-base/

Some might find that useful to know, I guess.

[madires]

Does anyone still use the UV method? My stock of inkjet transparencies is running out and the stationary warehouse I bought the last batch from doesn't seem to stock them anymore. In fact nobody seems to stock them anymore. Anyone know a reliable source?

Yes, I'm using a laser printer and transparent drawing paper (tracing paper). That's inexpensive and works great. BTW, disable the "toner saver mode" for printing the layouts to get nice black traces and areas.

[ptricks]

I have tried every method available for DIY PCB. The best detail you can get is going to be with the photo method. The toner transfer method works but I highly recommend buying a laminator, I did boards with the iron method and it is not the way to do this, it can get too hot, pressure is uneven.  One trick I learned for toner transfer is, after cleaning the PCB, drop the board in etchant until you see a solid color across the board surface,  once I started using the etchant rinse before transfer I never had problems getting the toner to stick and it worked for everything from normal printer paper to magazine paper.  One tip for those that have a hot air station, after you do the transfer you can go over the PCB with the hot air and heat up the toner and it will melt and fill in any of those speckled spots you might sometimes see.

[GK]

Does anyone still use the UV method? My stock of inkjet transparencies is running out and the stationary warehouse I bought the last batch from doesn't seem to stock them anymore. In fact nobody seems to stock them anymore. Anyone know a reliable source?

Yes, I'm using a laser printer and transparent drawing paper (tracing paper). That's inexpensive and works great. BTW, disable the "toner saver mode" for printing the layouts to get nice black traces and areas.

Hmmm..... I'm not not sure if my Epson inkjet would print successfully to tracing paper.

[smashedProton]

I'm interested to hear about laminatiors.  I laminate by hand with less than ideal results.   

[(In)Sanity]

I'm still stuck on the laser toner iron on method.   I've been able to produce 5 mil traces with no issues at all.   Double sided boards can be a bit tricky however.   I've been thinking more and more about finding some other cost effective methods.   PCB's really cramp my design ambitions.   If it wasn't for having to make them I would have thousands of circuits built up and running.   I had a really nice in circuit ESR meter fine tuned that even worked on batteries...only to have it never leave the breadboard.   Part of the game I guess.

Jeff

[ptricks]

I'm interested to hear about laminatiors.  I laminate by hand with less than ideal results.   

The laminator I use is  a scotch branded TL901, I didn't have to modify anything to use it and  I use boards that are in the .060 to .090 range , it also is a double roller , top and bottom heater unit so heat flow is on both sides not just one like some of the cheaper models.

http://www.amazon.com/Scotch-Thermal-Laminator-Roller-TL901/dp/B0010JEJPC

[MetraCollector]

Mmm, my hint about alkaline etching was untouched. But it is really a good method.

Who of you are capable to do a solder mask at home either ?
For few last years, I have put in home-made PCBs amount of money equalling value of multipling by 4 or 5 of value of PCBs I made. It is some kind of passion, making them at home.

Sorry about quality of copper traces in sample, but I forgot it in the solution of H2O2, H2O, HCl

[(In)Sanity]

This is an interesting little how to.

http://www.instructables.com/id/Toner-transfer-no-soak-high-quality-double-sided/#intro

[(In)Sanity]

Mmm, my hint about alkaline etching was untouched. But it is really a good method.

Who of you are capable to do a solder mask at home either ?
For few last years, I have put in home-made PCBs amount of money equalling value of multipling by 4 or 5 of value of PCBs I made. It is some kind of passion, making them at home.

Sorry about quality of copper traces in sample, but I forgot it in the solution of H2O2, H2O, HCl

I would love to be able to make pro looking boards at home.   Half the time I do at least one thing wrong and end up with a bodge wire.   So it would be nice to just make a new board to correct for any issues.   If I send them away to get made I still end up with that one issue.   Via's are a bit of a pain,  but not the end of the world.   I just make sure I don't route a via under a chip and then just use a pass thru wire.   Bit annoying..but it works. 

Jeff

[Harvs]

I've tried and tried with the PnP blue over the years.  I've never got decent repeatable results.  However, one thing I've noticed is I get wildly varying results depending on the printer used.  From pretty good to zero transfer at all.  So I wonder if the large variation people have in success has something to do with which printer/toner is used.