Trace and pad template?

Discussion in 'General Electronics Chat' started by spinnaker, Nov 16, 2010.

  1. spinnaker

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    I was wondering if there is such a thing as a trace and pad template? I am thinking of something like those flow chart templates except for traces and pads with various sizes.

    I use the transfer method but it would be nice to have a handy template to touch up some of the traces.
     
  2. thatoneguy

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    I think radio shack still sells the "Rub On" pads/stripes of various sizes, not sure if they are discontinued or not.
     
  3. jpanhalt

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    By chance, I saw that Datak rub-ons are still available at DigiKey. Having used that method myself, and I am sure several people here have had the same experience, that method was useful when all we had were IBM Selectric typewriters. With modern laser and inkjet printers, it is hard to justify the effort and frustration of using rub-ons.

    As for cut-out stencils, some people have suggested using a vinyl cutter.

    John

    Edit: Here's the DigiKey link: http://search.digikey.com/scripts/D...page_link=hp_go_button&KeyWords=datak&x=0&y=0
     
    Last edited: Nov 17, 2010
  4. spinnaker

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    I guess I should have been more clear. I already use the laser toner transfer method. Once in a while the traces need to be touched up with a marker.

    My hand is not all that steady and it is hard to draw a straight line. I was wondering if there was a template to help draw traces.
     
  5. Wendy

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    Are you trying to touch up the traces on the transfer? If so I don't think it can work. You can touch up the traces after the transfer though, either with a magic marker or the rub on transfers everyone is talking about.
     
  6. retched

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    You can use tape, or stencils, or whatever you like.

    As long as you keep the ink where you want the copper, you will be good to go.

    I have "fattened" up traces by taping off an area with standard Scotch tape and ran a few passes of Industrial Sharpie over the resulting gap.

    Worked-a-treat.

    It allowed for a higher current trace without having to re-print and line-up and transfer another layout.
     
  7. spinnaker

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    No I want to fix them after the toner is transferred to the copper.
     
  8. jpanhalt

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    Try the photo process, either MG or Injectorall (Digikey). I can give you the recipes for Injectorall. Never is a pretty strong word, but I have never had a problem with a trace using the photo process.

    John
     
  9. spinnaker

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    Do you have a problem with the tape lifting existing toner?
     
  10. retched

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    No.

    This is after the toner is WELL melted and adhered to the copper.

    If you did a half-decent job scuffing it up with some green or brown scotch-brite pads, and did a decent pressure job on the transfer, It is rather hard to get the toner off.

    I wouldn't try duct tape..but standard scotch tape does fine.
     
  11. Wendy

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    Either tape or a fine tip magic marker might do it. I'm fighting the same battle, it has been a while since I've transfered toner neatly (some of my recent stuff was pretty ugly). I'm trying it again for another project. I've finally had a decent transfer, after more than 20 attempts.

    Part of the problem is my laser printer can't handle thick paper any more, which is a PITA. No photo paper for me. I've resorted to using wax paper, which works well, but has a host of other issues, mostly in removing the paper after the transfer without mucking up the pattern. The transfer process evaporates all the wax. I tape the wax paper to regular paper to get it to go through my laser printer.

    I'm halfway convinced a lot of my problem is my iron is a cheap unit, the more expensive ones have more wattage (and more heat). I spend almost 10 minutes getting the toner to melt. I may make something similar to this project later...

    Project: Converting a hot roller laminator for toner transfer.

    Removing toner is easy, just use acetone to clean it entirely, then scotchbrite to clean the oxidation off. This I've become very good at (20 times on the same chunk of copper clad board).

    I'm going to try a new etchant, the 2:1 mix of muriatic acid (AKA, hydrochloric acid, used in swimming pools) and off the shelf hydrogen peroxide. I've heard good things about it, so time to try it and see.

    Tom Gootee's site is back up, it is a pretty comprehensive how to on transfer PCB techniques. He is also a member of this site.

    http://www.fullnet.com/~tomg/index.html
     
    Last edited: Nov 19, 2010
  12. spinnaker

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    I get mixed result too.

    I have two issues

    1. I don't get a good toner transfer is spots. I am fairly certain I have cleaned and scuffed the board properly.

    2. It seems to be that the ferric chloride starts to eat into the toner. Not all of the board is finished etching so I need to leave it in. Perhaps I should be using fresh echant each time?

    Hard to tell because I have not etched all that many boards.

    I do sometimes get very good results. I had great results with transferring toner as a silk screen (even though it is a bit crooked :) ).
     
  13. retched

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    Your toner may not be good for etching.

    Not all toner is.
     
  14. spinnaker

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    Yeah it is a cheap replacement toner. I was thinking about investing in a regular HP toner but it is probably more than I paid for the printer. :)
     
  15. Wendy

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    The blank spots is the same as my problem. My solution is to increase the amount of time leaving the iron on, as it is obvious it is not getting hot uniformly. Goes back to the iron is not good enough quality thing I mentioned.

    So I increase the time, put a piece of paper over the work so I can move the iron without moving the work or toner template, and set a timer. I still don't have consistent results to be an "expert".

    A laminator might address this. Reading other threads on other forums they feed the same thing through 8 - 10 times, which seems to work for them.

    I have another experiment I'm going to try. If I can get my hands on smooth aluminum ¼" thick or thicker, I'll put it on my electric stove to make a primitive hot plate, then use the iron on it. Drill a small hole 1" into the side for a thermocouple and it can be regulated relatively well.

    I could also flip the circuit up side down, and using a rolling pin for a laminator effect.

    I suspect everyone has to experiment to find what works for them. Acetone is cheap, so don't be afraid to throw a bad transfer away and start from scratch on the same piece of copper clad board. Eventually you'll find what works for you, take notes.
     
  16. spinnaker

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    Great minds think alike! I was thinking pretty much the same except your mind is much greater. :) Tthemcouple? How would that work exactly? What do you mean drills a hole side?

    You would just have one plate? I was thinking two and sandwich the board.
     
  17. thatoneguy

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    The best thing I've found for toner transfer is the "PC Board In A Box" laminator.

    I got one from DigiKey, it accepts thick PC Boards. With the special paper (quick and easy), or with photo paper (only messy to get paper off toner), 2 passes through and I rarely have anything that can't be touched up with a single tap of a sharpie.

    It's an ABC Personal Laminator, Model No: 1701897 I'm unsure if it was modified by PCB In a Box people, but it works great!

    Getting enough pressure evenly with an iron is difficult. Not too big of a deal except with fine pin pitch and running into smearing problems with too much pressure.
     
  18. Wendy

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    You treat thermocouples as a wire (it is actually two wires with a welded ball at the end). The ball is the actual sensor, but to get reliable readings you need to immerse the wire in back of the ball a bit. A lot of DVMs have a thermocouple feature, it reads temperature.

    One smooth very hot plate, and the iron on top. The iron is redundant at this stage, but man portable (as in can be handled by me).

    So far I haven't gotten hot enough to smear anything. This is the problem.

    A flat griddle might also work, though it is too thin. The thick plate would distribute the heat more evenly.
     
  19. spinnaker

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    Yeah I know what a thermocouple is. I was wondering how you would use it for this application. Just log your temp to try and get the ultimate temp?

    I have one of those flat top electric stoves. I might give the burner a try.
     
  20. retched

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    A few experiments with a temp controlled iron and some toner may be in order.

    A friend of mine had an iron he used for forming and coating RC airplane wings. I may be a little foggy on the numbers, but I am pretty sure it went up to around 500F.

    Finding the optimal melt temp of your toner would lead to more consistent results.. I would think ;)

    I have always used news paper and my hard wood floor.

    A soldering iron can be use to "tack-down" the print to the copper. Only takes a second

    I have used my clothes iron, set to highest, no steam. Let it sit in one spot for a 20 count, body weight for a 20 count, then move in an "ironing-motion" for about a 20 count.

    Let it sit for a few minutes then submerge and remove paper with a warm water bath.

    It would be nice to have some numbers to go by, temp-wise.. but I suspect it changes toner to toner.
     
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