New toner transfer technique!

Discussion in 'General Electronics Chat' started by spinnaker, Dec 6, 2010.

  1. spinnaker

    Thread Starter AAC Fanatic!

    Oct 29, 2009
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    I think I have come up with a great new toner transfer technique!

    This has to be the darkest most perfect transfer yet. With an iron I have always had some voids especially in the places where a large area of copper masked and runs near the edges of the board.

    Sorry I should have snapped some pics but I have a habit of coloring over some of the toner with a Sharpie because of the problems I was having. I should have snapped a picture first.

    Here is what I did.


    I printed my layout on a sheet of magazine paper.

    I have one of those flat top electric stoves. I suppose you could get a steel plate and use that on a gas or conventional electric stove.

    I heated the burner to around 200 degrees F.

    I place a couple of sheets of add paper on the burner (you may want to place a couple of paper towels first to prevent transfer of the ads to the stove).


    I placed the PCB copper side up with my layout on top of the copper.


    I placed a paper towel on top of the whole works. I did this after I realized print was being transferred to the rolling pin I used (below). You may want to use the paper towel to prevent your wife from hitting you with the rolling pin. :)


    I rolled a rolling pin over the board. After I was pretty certain the printout was racked down fairly well, I rolled the pin past the edges of the board. I rolled the pin for about ten minutes.

    I removed the board from the heat and dropped in in very hot water with dish washing soap. I soaked for 15 minutes or so and pealed off the paper.
     
  2. sceadwian

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    Jun 1, 2009
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    Not really a new technique. It's the same one you're just using what you have available.
     
  3. Wendy

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    Mar 24, 2008
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    Did the paper peel off as a piece? I haven't used soap in my hot water.

    I thought those flat stoves used induction and heated the pan metal, not their surface. If this is the case you heated the copper. Whatever works though.

    What was your etchant?
     
  4. spinnaker

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    No it did not come off in one piece. But it did come off layered as I wanted it too.

    This stove is not induction heat, Those are (or were) very expensive. This is just a regular stove with a flat top.


    I was using ferric chloride.

    I still have a couple issues. The ferric chloride is still eating a bit through the toner in some very small spots. I suspect I do not have the most ideal toner. It is a 3rd party replacement cartridge. But the pitting was far less then I have ever had. Probably because I am getting more of the toner transferred. Or it could be that I am monitoring the etching process a bit closer and pull the board the moment it is fully etched.

    I still have issues with liquid tin. I know this has nothing to do with the etching process but probably due to the fact I am not cleaning the board thoroughly. I think the evidence is that the center of the board tins fairly well but the edges seem to suffer.
     
  5. Wendy

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    I don't use liquid tin myself. It isn't necessary to use on the board, it makes it is pretty and easier to solder. Use scotch brite to clean the board (not steel wool, which will cause other problems).

    Did you warm the etchant first? Use a microwave and heat some water to boiling, then put the ferric chloride in with the lid off and let it sit for 10 minutes or so. Warm etchant will make for a smoother etching process.
     
  6. spinnaker

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    I heated a plastic tray of water to almost boiling. I then placed the container with the etchant inside that.

    I think I might invest is a aquarium heater.
     
  7. Wendy

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    The absolute top of line FeCl etchers spray the liquid on, and heat it besides. FeCl eats everything though (though it is safer than the HCl and H2O2 etchant) even the fumes, so I don't recommend this for home use. I'll try the HCL/H2O2 etchant a bit longer, and may get rid of my left over FeCl stuff.

    I used to service a FeCl etcher for Alcatel's photoshop, the metal parts were titanium.
     
  8. Markd77

    Senior Member

    Sep 7, 2009
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    Another use for the stove top is for etching. Just let it cool off a bit and put a metal dish with water in on top. Put your etchant contaner in there.
    I've been using that other type of etchant that likes 50 centigrade. The stove top is the easiest cheap way I've found to keep it that way for 10 minutes.
     
  9. Wendy

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    Don't forget to use a spacer. They a standard kitchen appliance, to keep water under the second pan as well as on the sides. I may have the name wrong, but they fit under the second pan inside the first.
     
  10. spinnaker

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    I am a klutz. I do not trust myself on the stove top.:) Instead of the aquarium heater, maybe I will pick up a cheap hot plate for the shop.
     
  11. retched

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    Dec 5, 2009
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    A double boiler is what you are looking for I believe bill.

    Or just a water bath.
     
  12. thatoneguy

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    Feb 19, 2009
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    Count the cost in time/prints boards you go through to get a good print.

    In the end, a hot roller laminator for around $100 gives solid results every time.

    Depending on number of copies and value of your time, the press n peel (aka pray and peel), or PCB in a box transfer papers are fairly failsafe compared to photo paper. The PCB in a Box "White RTF" is Awesome for adding a "silkscreen layer" to topside PC Boards. To make it look better, use Testors Transparent candy green (1601) first and let it dry before laminating the white RTF "silkscreen".

    All require a laser printer, but involve MUCH less annoyance and faults from incomplete transfer, or damaged transfer from removing the backing.
     
  13. Wendy

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    Actually, the quantity of bad prints is the learning curve. Once you have a technique that works for you it is gravy.
     
  14. nerdegutta

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    Dec 15, 2009
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    What about silk screen/solder mask? How do you to that?
     
  15. thatoneguy

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    Look at the details of PCB Fab in a box from digikey and distributor I linked above.

    It's a bit spendy, but allows close to fabhouse results, save for vias and drilled holes. Only masking resist and "silkscreen".
     
  16. nerdegutta

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    Oh... the link. Thanks.
     
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