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philba · 5th September 2006, 01:40 AM

I've used a lot of different papers for toner transfer. just about any glossy magazine paper will work. I've gotten good results with Time Magazine (thin), Cosmopolitan (heavier), A Lands End catalog and a few others I don't recall. I have also gotten very good results with ink jet paper (in a laser) and ok results with photo paper. I've also gotten decent result with water soluable PVA stock (Disolvy - for sewing patterns). The key issue is the paper must be coated to prevent the toner from soaking into the fibers of the paper. anything that is coated will work.

tunedwolf · 5th September 2006, 03:35 PM

Personally, I use a photographic process, I find that it yields repeatable work, especially for higher resolution/greater density or smt/mixed boards.
I used to coat my own boards on a large scale, then live off the stock for 6 months at a time, but now it's as cheap to just buy in pre-sensitised stock whenever I need it.
I know a lot of folks have hit and miss results with it though, but I find that generally it is because they often unknowingly alter their process each time.

Build yourself a proper exposure frame with a decent lamp that you can semi-permanently fix the height of and build in an accurate timer to control the lamp. Run a test strip for each new batch of board stock so you know exactly what the correct exposure time should be, what height the lamp should be to properly expose the whole board without shadow and what strength of chemicals are required. The major advantage of using a frame, is that you can get registration perfect if you are making double sided boards, something the Toner/contact method is very tricky to do with.

For the developing chemicals, mostly any caustic soda solution will do, you can get it from some hardware places or pharmacies, often it is sold as drain cleaner. Board stockists can give you non caustic stuff as well, but it's a little more costly. Use measuring spatulas and marked jugs for your make up water so you can repeat the solution strength with some degree of accuracy, remember you are aiming for consistent repeatable results. All you then need do each time you make a board is set your exposure timer, lamp height and chemical strength accordingly. I have heard all sorts of stuff like use distilled water etc over the years, but unless you are planning on keeping the chemicals in made up form for months at a time, it's better to just make up what you need. I usually use Malted Vinegar to neutralise the spent developer, and as a fixer for the developed board prior to etching. I also have a tray that I put cool clean water in to store the board between processes, I find that by keeping the board away from the air as much as possible there's much less chance of oxide build up causing dead spots in the etching process, and is especially required if I go on to tin plate the board, as is often the case with my boards.

Use cool water when developing the board, keep it at or below 15 degrees and the development process will be slow enough that you can watch things and correct them if the board is over exposed, or your development solution is too strong. After a bit of experience, you'll instinctively know how warm the solution needs to be just by holding your development tray in your hands. Usually a quick wash of the partially developed board in cold water is enough to stop the resist washing away before your eyes. Just remember that the warmer and stronger the solution is, the faster the development, to the point where it will wash your entire artwork away. Direct sunlight is to be avoided when handling the exposed board, but a dull overcast day generally allows me enough time to handle it during processing, on bright days, I usually just close the blinds over a bit. I used to use an ordinary yellow coloured incandescent lamp as a safe light because the films and board stock used to be really sensitive to daylight, but nowadays, the stuff can pretty much be handled in daylight for short periods without negative effects.

If you make sure your process is fairly stable and repeatable each time, you should have fantastic quality boards each time, but alas that's not always the case. Small variations in board stock mid batch etc can affect the development stage, but if you go slow with it, you can always stop the development by rinsing the board in cold water and add a smidge more caustic to your make up or warm it up a little to help an under exposed board clear, or dilute your already too strong solution to help an over exposed board.

I have also tried the Toner/contact method using various papers and had moderately good results with it, but I found that it's is strewn with the same pitfalls the photo process has, i.e lack of experience and confidence and lends itself to the self same process altering characteristics the photo process has for loads of folks, unfortunately it's the downside of being human, only with a differrent set of process steps.
Also the board processing is sloppy using an iron because of varying contact pressure, even heating, removal of air bubbles, oxides etc etc, there is not really any way I can see that you can manually make that both accurate and repeatable, there will always be differences. It's a matter of whether you can control those sufficiently to produce repeatable results. I personally couldn't and scrapped as many boards as I was happy with.

Obviously one off boards are an exception here, as either process usually yields a workable board eventually. The one thing that the Toner/contact method has to it's advantage, is that bare copper clad board stock is used, so it''s a little cheaper and you get to see where your artwork let you down before ruining the board in etchant, you can always scrub it and try again etc till you get it right. With the photographic process you would do the same thing, but to the contact artwork, and not the board, giving rise to running a dozen perfect boards from the same artwork. The photo process also has the advantage that unless you are coating your own board stock, you don't need to clean it of oxides etc before use, it is a pretty much repeatable process.

For one off boards, either method will give you a result if your careful, for high density or smt boards, or boards where you need to run a couple of dozen off, the photo process will lend itself better in my opinion. It's all an art form and takes a little time to master. Either way you produce your boards, if you are like me, you will stand back and think it's a thing of beauty every time onee turns out the way you want.

Look at it this way, it's like cutting glass, if you have no experience and little confidence whilst doing it, you'll end up with a gazillion broken bits, but show a little confidence and use a sharp cutter each time, and you'll have perfectly cut glass.

Ok that was a rant, I admit it, and I'm somewhat biased here too.
I have used the photographic process for 20+ years, and really only used the Toner/contact method for 20 mins, well, ok, I used it for about a week, but obviously not long enough to build that glass cutting confidence that others have mastered.

philba · 5th September 2006, 04:10 PM

While I use toner transfer, I'm not a die-hard about it. It's just a tool and all tools have their strengths and weaknesses. Just as the photo process does. One thing that I totally agree with - knowing how to use the tool is critical. It's a poor craftsman that blames his tools.

It took me a few boards to get TT down but now I get maybe one failure in 10 - usually because I rushed the cleaning process.

On the photo exposure boxes - get a junked scanner, it's perfect as an exposure box.

StopGo · 5th September 2006, 05:19 PM

Laser toner transfer has worked quite well for me. Though for me.. getting perfect results reliably took a little practice and I didn't get the wrinkles ironed out until I had made 5 or 6 PCB's. Here's some of my own guidelines.

- fill in as much copper as you can, toner sticks better if it's next to more toner.
- don't touch the paper especially the tracks
- rub copper with cleaning block, brush away debris with a 2" paintbrush, then paper towel with acetone.
- clean it a bit more than you think is neceasary
- especially round the edges
- tape the paper to the copper board so it can't move
- I make single sided boards and seem to always get better results when I heat the board from the non copper side.
- a good flat surface really helps
- use kitchen paper towels, two either side evens out the pressure from the iron.
- after ironing and weigh it down with an old lead acid battery until it goes cold.
- give the water time to do its job
- peeling works well only sometimes
- a soft toothbrush doesn't damage toner if it's stuck well.

Hero999 · 5th September 2006, 05:29 PM

Quote:

Originally Posted by HarveyH42

Hero, you throw this in everytime this topic comes up, but you never specify which grade magazine paper you use. There are atleast three typical grades, some magazines use them all in a single issue. Guess we can rule out the high gloss photo pages for obvious reason (stuck together most likely

), that leaves the regular gloss and the recycled news-print pages.

Thick high-gloss paper isn't much good in my oppinion because the ink sticks to the gloss but the gloss doesn't separate well from the paper when it's washed. Plain non-glossy paper is useless too because the ink soaks into the paper. I use the intermediate thickness medium-gloss paper (used for most pages in most magazines) because the ink sticks to the gloss which separates easilly from the paper when washed.

I'm thinking about experimenting with using plain paper covered with a dry thin layer of water soluble paper glue. My theory is that the ink will stick to the glue which will wash off when soaked in water.

One thing I've found is that after ironing you need to leave the board to cool for awhile. Also it needs to be left to soak for a reasonable lenghth of time otherwise the paper will remove the ink when it's peelled off.

mramos1 · 5th September 2006, 05:31 PM

StopGo. That is what I do as well and they dome out nice. Only new item is I will let them soak in the warm water longer, less toothbrush required.

I do heat the copper side and to no sit a battery on it, but all the rest works for me.

EDIT: Hero999, yep I let them cool and I now soak them a little longer. Also, I have been tring other paper, medium gloss and a lot better than gloss tring to scrape that white stiff off the copper.

Let me know how the paper glue works, I have a compressed air aresol can I can add some water and spray it on..

justDIY · 5th September 2006, 08:39 PM

Quote:

Originally Posted by markland556

I only have InkJet printers in my home, they are nice, but i dont know if they are up to the task.

Id really like to make some sort of setup to where i can just make a design in Eagle, print it at home and get along making it.

i once thought laser was required, since nearly all the sites detailing the photolithographic method (photographic method) talk about laser printing on acetate.

I've recently switched to doing all my artwork on inkjet printers ... the inkjet rivals laser in terms of resolution... sure you might have a laser printer that claims 1200dpi, but the particle size of the toner is still a limiting factor ... modern inkjets spray ink much finer than any laser toner ... and this results in much finer pitch and cleaner lines on the PCB

here's links to my ramblings on photolithography:
theory http://projects.dimension-x.net/archives/77
practice http://projects.dimension-x.net/archives/82

StopGo · 5th September 2006, 09:02 PM

Quote:

Originally Posted by justDIY

i once thought laser was required, since nearly all the sites detailing the photolithographic method (photographic method) talk about laser printing on acetate.

I've recently switched to doing all my artwork on inkjet printers ... the inkjet rivals laser in terms of resolution... sure you might have a laser printer that claims 1200dpi, but the particle size of the toner is still a limiting factor ... modern inkjets spray ink much finer than any laser toner ... and this results in much finer pitch and cleaner lines on the PCB

Inkjets might work for photgraphic techniques but for TT (toner transfer) techniques. (TTT's)

it won't work! No toner .. no transfer.. see?

Hero999 · 5th September 2006, 10:05 PM

You can always photocopy it. To be honest I'd go out and buy a cheap laser printer since the toner lasts for ages, I bought my old Cannon LBP-660 back in 1997 and I onlt needed a new toner last year.

HarveyH42 · 5th September 2006, 10:56 PM

Has anyone noticed that the guy that start this thread hasn't post here since the great debate resumed? Kind of lost sight of what Mark was looking for to begin with. He just wanted to make a couple of boards a month, nothing fancy or complicated. Toner is great for beginners, but photoresist will most likely give the best final results.

We probably scared the poor guy back to doing business with the chinese boardmakers (our economy is a few dollars weaker...).

muki55 · 6th September 2006, 12:35 AM

Quote:

Originally Posted by mramos1

Cheap picture paper works well.. I have only done on magazine paper one. Was bad, cheap thin paper, the laser crunched it up.

I think you're wrong, I will not go back and search the threads. BUT, I think it was an adult magazine mentioned way back in a thread.

Maybe not..

I still want to try the magazine paper. It makes since. But the lexmark photo paper and other papers at 100 sheets for $12.99.. They work, you just have to learm to let them soak long enough before you peel the paper off.

nice post!!!
thanks i'll try your way

Centretek · 22nd February 2008, 01:26 PM

"Sharpie" permanent markers make a reasonable etch resist pen. For very simple boards, I have hand drawn the pattern and etched with ferric chloride solution.
You can make photo masks with an inkjet printer and overhead transparency sheets. Just make sure the printer is set to B/W and best photo quality. My Epson R310 works fine.

**3v0** · 22nd February 2008, 02:30 PM

I have been talking about the tip on the Pulsar site for simulating laminator action with an iron.
Tip #3: "Roll your own!"

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5th September 2006, 01:40 AM	(permalink)
philba	I've used a lot of different papers for toner transfer. just about any glossy magazine paper will work. I've gotten good results with Time Magazine (thin), Cosmopolitan (heavier), A Lands End catalog and a few others I don't recall. I have also gotten very good results with ink jet paper (in a laser) and ok results with photo paper. I've also gotten decent result with water soluable PVA stock (Disolvy - for sewing patterns). The key issue is the paper must be coated to prevent the toner from soaking into the fibers of the paper. anything that is coated will work.

5th September 2006, 03:35 PM	(permalink)
tunedwolf	Personally, I use a photographic process, I find that it yields repeatable work, especially for higher resolution/greater density or smt/mixed boards. I used to coat my own boards on a large scale, then live off the stock for 6 months at a time, but now it's as cheap to just buy in pre-sensitised stock whenever I need it. I know a lot of folks have hit and miss results with it though, but I find that generally it is because they often unknowingly alter their process each time. Build yourself a proper exposure frame with a decent lamp that you can semi-permanently fix the height of and build in an accurate timer to control the lamp. Run a test strip for each new batch of board stock so you know exactly what the correct exposure time should be, what height the lamp should be to properly expose the whole board without shadow and what strength of chemicals are required. The major advantage of using a frame, is that you can get registration perfect if you are making double sided boards, something the Toner/contact method is very tricky to do with. For the developing chemicals, mostly any caustic soda solution will do, you can get it from some hardware places or pharmacies, often it is sold as drain cleaner. Board stockists can give you non caustic stuff as well, but it's a little more costly. Use measuring spatulas and marked jugs for your make up water so you can repeat the solution strength with some degree of accuracy, remember you are aiming for consistent repeatable results. All you then need do each time you make a board is set your exposure timer, lamp height and chemical strength accordingly. I have heard all sorts of stuff like use distilled water etc over the years, but unless you are planning on keeping the chemicals in made up form for months at a time, it's better to just make up what you need. I usually use Malted Vinegar to neutralise the spent developer, and as a fixer for the developed board prior to etching. I also have a tray that I put cool clean water in to store the board between processes, I find that by keeping the board away from the air as much as possible there's much less chance of oxide build up causing dead spots in the etching process, and is especially required if I go on to tin plate the board, as is often the case with my boards. Use cool water when developing the board, keep it at or below 15 degrees and the development process will be slow enough that you can watch things and correct them if the board is over exposed, or your development solution is too strong. After a bit of experience, you'll instinctively know how warm the solution needs to be just by holding your development tray in your hands. Usually a quick wash of the partially developed board in cold water is enough to stop the resist washing away before your eyes. Just remember that the warmer and stronger the solution is, the faster the development, to the point where it will wash your entire artwork away. Direct sunlight is to be avoided when handling the exposed board, but a dull overcast day generally allows me enough time to handle it during processing, on bright days, I usually just close the blinds over a bit. I used to use an ordinary yellow coloured incandescent lamp as a safe light because the films and board stock used to be really sensitive to daylight, but nowadays, the stuff can pretty much be handled in daylight for short periods without negative effects. If you make sure your process is fairly stable and repeatable each time, you should have fantastic quality boards each time, but alas that's not always the case. Small variations in board stock mid batch etc can affect the development stage, but if you go slow with it, you can always stop the development by rinsing the board in cold water and add a smidge more caustic to your make up or warm it up a little to help an under exposed board clear, or dilute your already too strong solution to help an over exposed board. I have also tried the Toner/contact method using various papers and had moderately good results with it, but I found that it's is strewn with the same pitfalls the photo process has, i.e lack of experience and confidence and lends itself to the self same process altering characteristics the photo process has for loads of folks, unfortunately it's the downside of being human, only with a differrent set of process steps. Also the board processing is sloppy using an iron because of varying contact pressure, even heating, removal of air bubbles, oxides etc etc, there is not really any way I can see that you can manually make that both accurate and repeatable, there will always be differences. It's a matter of whether you can control those sufficiently to produce repeatable results. I personally couldn't and scrapped as many boards as I was happy with. Obviously one off boards are an exception here, as either process usually yields a workable board eventually. The one thing that the Toner/contact method has to it's advantage, is that bare copper clad board stock is used, so it''s a little cheaper and you get to see where your artwork let you down before ruining the board in etchant, you can always scrub it and try again etc till you get it right. With the photographic process you would do the same thing, but to the contact artwork, and not the board, giving rise to running a dozen perfect boards from the same artwork. The photo process also has the advantage that unless you are coating your own board stock, you don't need to clean it of oxides etc before use, it is a pretty much repeatable process. For one off boards, either method will give you a result if your careful, for high density or smt boards, or boards where you need to run a couple of dozen off, the photo process will lend itself better in my opinion. It's all an art form and takes a little time to master. Either way you produce your boards, if you are like me, you will stand back and think it's a thing of beauty every time onee turns out the way you want. Look at it this way, it's like cutting glass, if you have no experience and little confidence whilst doing it, you'll end up with a gazillion broken bits, but show a little confidence and use a sharp cutter each time, and you'll have perfectly cut glass. Ok that was a rant, I admit it, and I'm somewhat biased here too. I have used the photographic process for 20+ years, and really only used the Toner/contact method for 20 mins, well, ok, I used it for about a week, but obviously not long enough to build that glass cutting confidence that others have mastered.

5th September 2006, 04:10 PM	(permalink)
philba	While I use toner transfer, I'm not a die-hard about it. It's just a tool and all tools have their strengths and weaknesses. Just as the photo process does. One thing that I totally agree with - knowing how to use the tool is critical. It's a poor craftsman that blames his tools. It took me a few boards to get TT down but now I get maybe one failure in 10 - usually because I rushed the cleaning process. On the photo exposure boxes - get a junked scanner, it's perfect as an exposure box.

5th September 2006, 05:19 PM	(permalink)
StopGo	Laser toner transfer has worked quite well for me. Though for me.. getting perfect results reliably took a little practice and I didn't get the wrinkles ironed out until I had made 5 or 6 PCB's. Here's some of my own guidelines. - fill in as much copper as you can, toner sticks better if it's next to more toner. - don't touch the paper especially the tracks - rub copper with cleaning block, brush away debris with a 2" paintbrush, then paper towel with acetone. - clean it a bit more than you think is neceasary - especially round the edges - tape the paper to the copper board so it can't move - I make single sided boards and seem to always get better results when I heat the board from the non copper side. - a good flat surface really helps - use kitchen paper towels, two either side evens out the pressure from the iron. - after ironing and weigh it down with an old lead acid battery until it goes cold. - give the water time to do its job - peeling works well only sometimes - a soft toothbrush doesn't damage toner if it's stuck well. __________________ 1 0 1 1 0 1 0 1 1 0 1 1 0 1 0 1 1 0 1 Last edited by StopGo; 5th September 2006 at 05:24 PM.

5th September 2006, 05:31 PM	(permalink)
mramos1	StopGo. That is what I do as well and they dome out nice. Only new item is I will let them soak in the warm water longer, less toothbrush required. I do heat the copper side and to no sit a battery on it, but all the rest works for me. EDIT: Hero999, yep I let them cool and I now soak them a little longer. Also, I have been tring other paper, medium gloss and a lot better than gloss tring to scrape that white stiff off the copper. Let me know how the paper glue works, I have a compressed air aresol can I can add some water and spray it on.. Last edited by mramos1; 5th September 2006 at 05:34 PM.

5th September 2006, 10:05 PM	(permalink)
Hero999	You can always photocopy it. To be honest I'd go out and buy a cheap laser printer since the toner lasts for ages, I bought my old Cannon LBP-660 back in 1997 and I onlt needed a new toner last year. __________________ I also post at the following sites: http://www.stop-microsoft.org http://www.heated-debates.com Screen name: Aloone_Jonez

5th September 2006, 10:56 PM	(permalink)
HarveyH42	Has anyone noticed that the guy that start this thread hasn't post here since the great debate resumed? Kind of lost sight of what Mark was looking for to begin with. He just wanted to make a couple of boards a month, nothing fancy or complicated. Toner is great for beginners, but photoresist will most likely give the best final results. We probably scared the poor guy back to doing business with the chinese boardmakers (our economy is a few dollars weaker...).

22nd February 2008, 01:26 PM	(permalink)
Centretek	"Sharpie" permanent markers make a reasonable etch resist pen. For very simple boards, I have hand drawn the pattern and etched with ferric chloride solution. You can make photo masks with an inkjet printer and overhead transparency sheets. Just make sure the printer is set to B/W and best photo quality. My Epson R310 works fine. __________________ A conclusion, is the point reached when you stop thinking. Last edited by Centretek; 22nd February 2008 at 01:30 PM.

22nd February 2008, 02:30 PM	(permalink)
3v0	Simulated laminator action I have been talking about the tip on the Pulsar site for simulating laminator action with an iron. Tip #3: "Roll your own!" __________________ search engine for electronic parts Junebug USB PIC programmer kit., USB Bit Wacker, Homepage The 15 Minute Printed Circuit Board! (+drill time)