First time failure: Toner Transfer Method

Discussion in 'General Electronics Chat' started by spinnaker, Feb 24, 2010.

  1. spinnaker

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    I tried the toner transfer method tonight. It failed. It transferred about 2/3 fairly well. In the remaining, half of that was spotty while the rest did not transfer at all.

    I prepared the board by buffing it with steel wool.

    Should I have Scotch Brite pads?

    Now that I did a search, I know what they are. I now realize I have some. I am such a bachelor. :)

    I then cleaned the board vigorously with acetone.


    I printed the PCB layout on a page from a 2009 calendar. It has a glossy surface and I figured it was a good choice.


    One thing, there was a delay of about an hour or so from when I printed the PCB to when I started to iron.

    Should I start ironing right after printing?


    I gave moderated pressure over all and then started moving the iron around.

    I did not actually use the very tip of the iron but did lift it up on edge to apply a bit more pressure.

    I ironed for about 5-10 minutes. I really should have timed it.


    Where did I go wrong? Can I expect a failure the first coupe of times?
     
  2. retched

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    Never want to use steel wool. Leaves particles behind, no matter how hard you try to get rid of them, and they will rust and hinder adhesion of the toner. (As you now see) And your paper choice was an unfortunate bad choice. Grab a Best Buy circular. (Or any thin gloss type ad). The "glossy" paper is a variety of layers that leaves much to be desired.

    What temperature did you set the iron to? Did you LEAN into it pretty hard? Did you have the steam off?(I hope)
     
  3. spinnaker

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    I think I see one problem. Looks like my printer was not set to highest quality by default. And dithering was on. PCB Express does not let you set printer properties!!!

    Looks like I will need to print to a PDF then print using Adobe Reader. Or set my defaults tot he highest quality in control panel.

    I wish PCB Express would let you set print properties . :(
     
  4. spinnaker

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    Is that copper toast? or can I save it?

    Steam Off.

    Cotton Setting.


    No I did not lean real hard. I read you can sometimes press too hard and smear it.
     
  5. BMorse

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    Put some butter on it and save it for breakfast...;)

    You can set your printer properties yourself by going to your printers folder in the control panel or in the printers folder from the start menu.......

    only if you let the paper slide on the copper while ironing...... and keep the Iron flat on the piece, do not tilt it to the side or use the tip to rub it, you need to apply firm even pressure as you iron it, and you can't "over iron" it, if you are unsure, keep ironing it until you feel it is done and you feel it is sufficient.....
     
  6. spinnaker

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    Yeah that is what I meant by going to the control panel.


    Seriously, should I even bother with that piece of copper any more?
     
  7. BMorse

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    Well as Retched said, you pretty much embedded it with small steel wool particles, which will rust and cause problems later on with your circuit, and the toner transfer will most likely not take no matter how you iron it. I would start with a fresh board, save that one for another use later, maybe you can use it to do a "manhattan" style pcb later on.....
     
  8. spinnaker

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    Thanks for the tips you two.

    One last question. Some say to preheat the cooper before placing the paper and others say don't. What is the best way?


    Oh also read a tip to use a dowel rod when ironing, Supposedly, it bends the copper a bit, giving a better transfer.
     
  9. BMorse

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    I have done it both ways, and I do never really seen a difference on how it comes out, so pre heat or not to pre heat, is really up to you.

    As for the dowel technique, I have heard of people using that technique, where they place a dowel under the PCB and roll over it, but to me it seems more of a hassle trying to move the iron around on the PCB as you "roll" the PCB on the dowel, it is like patting the top of your head and rubbing your belly at the same time.....

    I always just used a bath towel (or similar, those thick ones) and folded that in half, and then in half again and layed that over the counter and that is what I ironed my boards on... the towel acts as an automatic leveler for the board as long as you apply firm pressure with the flat side of the iron as you move it about the board while ironing.
     
  10. retched

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    As for preheating, I would wait to try it. If you preheat too warm, when you go to set the transfer, it may stick if it touches before you get it positioned properly. I never have preheated, seems to me, the iron will heat it plenty.

    And about the pressure, for super thin traces, (less than 1mil) you can "smash" them a little wide, supposedly. I never print that small. But I have also heard that hard pressure can help alleviate or close pinholes. I would prefer that.

    Keep that steel wool far, far away. In a distant galaxy...nevermind
     
  11. spinnaker

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    Yeah I figured that with pre heating, you are pretty much committed after placing the paper.

    You say to use a Harbor Freight ad?? The one I have is like normal paper. Doesn't it have to have a glossy finish on it? I assumed that is what people meant my magazine paper.
     
  12. retched

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    Look at the glossy ad, like best buy has. The grocery store, plain paper type, doesn't work.

    How did you remove the paper? You soaked it in warm water, correct? If you just pull it off dry, you can remove the toner from the board. (Especially if you under-iron)
     
  13. spinnaker

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    Near perfect results this time.

    One issue with a trace not connected. But that was a design flaw on my part. Tough to see some of the traces in PCB connect. I think I should turn off silkscreen layer. That might help.

    A couple of samll places around the edges where toner did not stick. I am guessing either I did not clean good enough or did not press hard enough around the edges.

    I should be able to fix all of these with a Sharpie.


    Thanks for all of the advice. I think it really helped.



    I will etch tomorrow.


    Then on to drilling. All I have is the smaller Ryobi bench drill press. Should I attempt it or get a Dremel? I would rather not spend the cash right now.
     
  14. SgtWookie

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    Try your Ryobi press.

    If the chuck has any runout, you will snap the small drill bits. I also have a Ryobi press; the arbor the chuck mounts on was damaged when I received it, and I didn't notice the damage until after I tried drilling small holes. Snap, crackle pop went the small drill bits. I managed to file down the damaged part of the arbor so the chuck runs true now.
     
  15. spinnaker

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    Other than trying it, how do I know it is running true?
     
  16. SgtWookie

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    Put a small drill bit in the chuck, and see if it wobbles as it spins.

    If you want to check the runout, you will need a dial indicator (a special kind of micrometer) mounted on a block, and a piece of drill rod - or the shaft portion of a larger drill.

    Low quality three-jaw chucks are pretty bad. My Ryobi came with a decent chuck, but as I said, it was damaged before I got it, but I managed to fix it. Collet-type chucks are generally much more accurate.

    [eta]
    Here's an article that's related: http://www.precisebits.com/tutorials/spindle_runout.htm
     
  17. spinnaker

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    Thanks Sarge. I might be picking up a Dremel anyway becuse of the following.

    Overall, the etching when well.


    There are a few spots where the edges and pads are a bit ragged. I figure I can clean these up with a Dremel.

    But what went wrong and how do I prevent this in the future? Did I press too hard? or maybe the paper shifted bit?


    Also I had a couple of voids that I filled with a black Sharpie. It did not do a very good job of protecting that area. Any tips on improving that in the future?

    The good news is that all of those areas were on my filled plane. For some reason, it was the filled plane that did not turn out very well.


    Anyone know if the Harbor Freight rotary tool fits in the Dremel press?
     
  18. SgtWookie

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    I usually wind up with a few "light" areas. I find a Sharpie doesn't work very well. I use red Staedtler Lumocolor pens for touch-ups that I special-ordered from a local art supply house that work well. You might try nail polish.

    Sounding like a broken record here, but I use a Scotchbrite pad in a drill press to scratch the copper surface, clean it off well with acetone (several times) and use an iron that's pre-heated to 300°F +/- 20°F. I use a flat piece of plywood for a base, a layer of paper towel over that, then the board face up, then the transfer on top of the board, and then another paper towel over the top of that. I put the iron on top of that, and don't move it for the first 15 seconds or so.

    You're going to have to experiment and find out what works or doesn't work for yourself.

    Laserprinters can have a hard time getting enough toner in the large copper fill areas. Turn off any printer enhancements, use low resolution, and set it as dark as it'll go.
     
  19. jbeng

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    Sep 10, 2006
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    To repair your circuit before etching, I recommend Sharpie Industrial, not a regular Sharpie. A regular Sharpie has ink which is somewhat water soluble, which could cause problems during etch. A Sharpie Industrial is not water soluble.

    I realize you are using the toner-transfer method, which I have never used. I have always used photo-etch and direct-plot methods. However, I have been cleaning copper-clad pcb stock with steel wool for over 25 years and have never had this problem. Is this a problem which is unique to the toner-transfer method?
     
  20. spinnaker

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    Yeah I used a Scotch Brite and really scrubbed it but I did not do the drill press thing.


    I will have to try that next time. Do you just pinch it in the chuck?


    I did really scrub it well with acetone after scrubbing with Scotch Brite.


    All enhancements were turned off. I used the highest DPI it would go. Turned off toner safer.



    What would have caused the few ragged trace edges? Too much pressure?
     
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