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Ordinary carbon paper instead of TRF Green


Gromit
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I've never heard of it so I Googled it.

http://www.pulsarprofx.com/pcbfx/main_site/pages/products/toner_foils/toner_foils.html

Some people I've met on other forums swear by expensive proprietor papers like this but I wouldn't waste my money on it. I've has perfectly acceptable results using clay covered magazine paper.

Their website contains all sorts of misinformation.

Toner is a very porous material. If left alone and the board was etched' date=' you'd wind up with pitted surfaces or even hairline breaks from cracks that were too small to see with the naked eye.[/quote']
No, not in my experience. I've made plenty of board using magazine paper and I've met people who've had good success with plain printer paper. I'm not doubting that it may increase the reliability of the process but there are more cost effective and reliable solutions available such as the photo process.


Who cares? It's a silk screen which is just there to act as a guide for placing the components. Fair enough, white might look better but I don't think it justifies the extra cost and I've seen commercial PCBs with a black silk screen before. The only problem I've found is that the toner can be easily scratched off but that can be solved by covering it with a thin layer of conformal coating which is far more cost effective.

Attached are some pictures of a board I made using toner transfer. It's the first time I bothered with a silk screen and whist, it's not perfect, it's more than good enough to serve its purpose.

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I have been using the toner method for years  with no problems. I tried the TRF white, thought it would be nice to have a pretty silk screen but I couldn't get it to transfer right.  I tried a landury iron, and a laminator. neither would work right. I guess it all depends on the amount of toner that is used. If the toner is to thin the TRFwon't stick to it. Oh well it was just a test, my boards look fine with just black silk screenning.
       If I every got real serious about silkscreening I would invest in the real silkscreen set-up and not waste my money on TRF junk
  gogo

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Thank you all for your answers! I found it on http://www.solidfluid.co.uk/sfsite.php/0000027F
The reason I ask this is because I can't get a uniform results: sometimes is pitting minimal with one sort
of magazine paper, sometimes is PCB unusable... (I always use laminator with same settings).

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If you're struggling with magazine paper then by all means give it a go. I know that the type of toner is a factor, perhaps Pulsar have a point about some manufactures of toner but they generalised too much: the toner I use works perfectly.

It's probably worth a go, before giving up and using the photo process which will give consistant results, regardless of the toner.

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Ok, I will not give up - after all some PCBs have turned out quite well...

@gogo2520: If you are using magazine paper you will always have white residues of paper,
and white TRF certainly won't stick to PCB! I use gummed paper for this (it's much cheaper than
Pulsar's) - dextrin coating dissolves in water and only pure toner remains.

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Don't worry too much about the residue, just soak it in water and remove as much as possible by soaking it in water and rubbing it very genitally. Paper lets the etchant through so, it just takes a little longer. If you're worried because there are bits of paper stuck in critical places i.e. between IC pins, just remove them with a pin or needle.

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  • 2 weeks later...

Well, I tried to use carbon paper, but to no avail. I just got a lot of mess. The dye from CP is spilled all over the PCB. I had a lot to clean with a toothbrush and detergent to remove CP pigment from it! I have no idea is some of pigment remained on toner. In attached image you can see final result - left half of the PCB was covered with carbon paper! Left image is scanned after laminating, right image after etching! I don't see any differences.
On the other hand gummed paper proved to be good - you can see the lowest part of PCB where is the larger area of copper - there is no pitting at all, but on some traces there are still more or less "rashes"! After laminating (10 passes, just to be sure) PCB is left in the water to soak for about 10-15 minutes, and then gummed paper fall off by itself in one piece! Only pure toner remains, without paper residues.
Now another problem emerges (that problem has appeared before also - with different types of paper): even after very aggressive cleaning with toothbrush traces REMAIN UNDAMAGED, BUT when I put the PCB in acid (HCl+H2O2 @ 25

post-60721-14279144293158_thumb.jpg

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Hello Gromit
  to bad about the carbon paper not working,I was going to try it myself, but what you said after your test I think I will pass and avoid the mess.
  When I clean my boards I use a green scrub pad with some kitchen scrub powder. then whipe it with a little acid tone to remove any grease .
  I have a laminator but rather use a cloths Iron instead. the laminator doesn't seen to work as good. the only problem with the cloths iron is pressing to hard with it, the traces can flat en out and fill out gaps were you don't them filled.
  I don't know what you mean by gummed paper or not sure what it is. like I said before I use office gloss paper it has a clay finish on it to help smooth it or the ink out so its has that gloss photo finish. When I  am ready to remove the paper all I have to do is soak it in warm water for a few minutes an the paper almost falls off. but ya I can still see some fibers of the paper still hanging on to the toner.

to bad about the carbon paper
                      have fun
                        gogo

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Thanks for fast replies!

@gogo2520: As I said I found this on site http://www.solidfluid.co.uk/sfsite.php/0000027F . I contacted Mr.Andy from SolidFluid and you can see what he answered to me in attached TXT file! I did not want to discourage you about the use of carbon paper - maybe my carbon paper was not the right type. About "gummed paper"; according to the dictionary "GUM=any of various substances (soluble in water) that exude from certain plants; they are gelatinous when moist but harden on drying" - hence the name. It is an ordinary sheet of paper with water activated glue layer on one side - it can be white (you can find it on ebay, just type "gummed paper") or colored collage-paper (for children  :)) that I use. You print on glue side: it seems that this layer of glue very well attract the toner particles! After laminating (or ironing) starch-based adhesive is dissolved in water leaving pure toner image on copper without traces of paper (very important if you use TRF White for silk-screening!). Any eventually remaining pieces of paper you can easily put away by rubbing with finger. Btw. I am surprised that you are not satisfied with the laminator - which type you use? It must be with two heated rollers (I use GBC).

@Hero999: This is what makes me really wonder! Of course, it is possible that I contaminate the toner after printing, BUT as I said it seems that the toner stick to the copper extremely well! You can scratch it, scrape it, brush it (I do not know more English words for this  :(), put PCB in cold and hot water and even 0,1 mm tracks remain intact!?! But when the PCB comes in acid some of traces simply detach from copper!? You can see in the picture that I attached before: for example "U-shaped" trace marked as 0,20 mm completely separated from board while very close traces (including letters) remained! Perhaps the acid was too strong, I really don't know...

Any suggestions would be appreciated!

SolidFluid.txt

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