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Subject: Re: Toner transfer problems

From: "alienrelics" <alienrelics@...>
Date: 2010-05-04

You are being very imprecise in your wording.

The paper that stickers come on is not wax paper, it is a plastic coated paper similar to silicone release paper.

There are many kinds of Tshirt transfer paper. Inkjet Tshirt transfer paper will -not- work as it is coated with a plastisol that covers the entire sheet, and will transfer the entire area to the copper. There are other types for inkjet dye sub that act only as a carrier, and another type for laser dye sub that also acts only as a carrier but with different properties. And yet another for a combination process that is used with regular color laser toner, that in a two step process transfers only the area covered by toner.

Steve Greenfield

--- In Homebrew_PCBs@yahoogroups.com, Andrew Villeneuve <andrewmv@...> wrote:
>
> That stuff, as I understand it, is simple wax paper.
>
> I tried iron-on T-shirt transfer paper, which appears to be very similar,
> and didn't require any soaking to remove, but found it very difficult to
> align because it never sticks to the board.
>
> Then again, I've improved many other parts of the process since giving up on
> wax paper, so it might be worth a revisit.
>
> -Andrew
>
> On Mon, May 3, 2010 at 6:40 PM, bownes <bownes@...> wrote:
>
> >
> >
> >
> > First off, thanks for the followup after soliciting advice. It's a big help
> > to those who come later!
> >
> > I've had similar issues with transfer methods no matter what I used for a
> > transfer medium, be it paper, magazine paper, photo paper, press&peel blue,
> > etc. The best luck I've had for boards that didn't require sub 0.02" pitch
> > was the paper used for peel off mailing labels after the labels have been
> > peeled off.
> >
> > --- In Homebrew_PCBs@yahoogroups.com <Homebrew_PCBs%40yahoogroups.com>,
> > Andrew Villeneuve <andrewmv@> wrote:
> > >
> > > With a lot of help from this list and a lot of experimentation, I'm
> > having
> > > much better success with my toner transfers. The process that finally
> > ended
> > > up working for me for creating my first usable double-sided board went
> > like
> > > this:
> > >
> > > 1) Discard overused boards. It's true you can transfer toner onto a board
> > > and then clean it back off and try again if it doesn't come out the first
> > > time. I had diminishing returns after my seventh or eighth try, and found
> > > it better to stop trying to salvage the board.
> > >
> > > 2) Line up the both sides of the board. I held the two sheets of magazine
> > > paper up to a worklight to line everything up, and then taped them
> > together
> > > on one side with ordinary Scotch tape.
> > >
> > > 3) Clean board blank with acetone, scour with Scotchbrite pad, clean with
> > > dish-soap and hot water.
> > >
> > > 4) Pre-heat board to about 200F.
> > >
> > > 5) Place the board between the taped-together patterns, using the
> > taped-edge
> > > as a guide.
> > >
> > > 6) Provide 1-minutes of constant pressure with the iron, then about
> > > 5-minutes of moving pressure.
> > >
> > > 7) Flip the board and repeat.
> > >
> > > 8) Drop the still-hot board immediately into hot water for 10-minutes.
> > >
> > > 9) Remove paper. Touch up any broken traces with a sharpie (industrial
> > > permanent ink, micro-fine point). Break any shorted traces with an x-acto
> > > knife.
> > >
> > > 10) To ensure that both surfaces of the board get evenly etched, I put
> > small
> > > squares of foam mounting tape in inconspicuous corners of the bottom of
> > my
> > > board. I use the 3M kind - this stuff's about 3-4mm thick, which gives
> > > enough clearance from the bottom of the tank. I left the paper on one
> > side
> > > so it wouldn't stick to the tank.
> > >
> > > 11) I submerged the board in FeCl in a simple closeable plastic
> > container.
> > > I held it over the stovetop on medium heat and hand-agitated the tank...I
> > > didn't measure the temperature here, but it was just cool enough to be
> > able
> > > to easily hold the tank without gloves.
> > >
> > > I checked the progress of the etching intermittently, and found it barely
> > > took 5 minutes to get complete removal of unwanted copper without any
> > > etching into my traces. I dunked the board in cool water in a separate
> > > plastic container to stop the etching, and now have a nice looking,
> > > perfectly aligned double-sided board ready for drilling.
> > >
> > > -Andrew
> > >
> > > On Sun, Apr 18, 2010 at 7:03 PM, andrewmv@ <andrewmv@>wrote:
> >
> > >
> > > >
> > > >
> > > > I've just started attempting my first PCBs with the toner transfer
> > method,
> > > > and I'm consistently getting terrible results.
> > > >
> > > > Some sections of the pattern transfer flawlessly to the board, while
> > others
> > > > stay on the paper. I've tried varying heat, pressure, and ironing time,
> > but
> > > > my results are always similar.
> > > >
> > > > It never seems to be the same parts of the pattern that come though,
> > but I
> > > > never get the whole thing.
> > > >
> > > > My current process is:
> > > >
> > > > 1) Print the patterns in black toner on medium-gloss photo paper with a
> > > > Dell 5310n laser printer at my office.
> > > > 2) Scour the board blank in two orthogonal directions with 150 grit
> > > > sandpaper
> > > > 3) Clean the board blank with pure acetone
> > > > 4) Preheat the board to about 150 degrees Fahrenheit with an electric
> > > > clothes iron. I'm measuring with a handheld infrared HVAC thermometer.
> > > > 5) With the iron at about 400 degrees, I place the pattern toner-side
> > down
> > > > on the board, and apply pressure with the iron. The pattern almost
> > > > immediately fuses to the copper, as I've seen suggested it should, and
> > I
> > > > move the iron around the pattern regularly, applying a least two full
> > > > minutes of heat and pressure to every part of the board.
> > > > 6) I immediately place the board and paper into a bowl of hot water,
> > and
> > > > let it soak for 10-20 minutes.
> > > >
> > > > I've tried variations on this...I initially skipped the scouring,
> > cleaning,
> > > > or preheating the board. I've tried using mild pressure all the way up
> > to my
> > > > full body weight. None of these significantly improved or worsened
> > results.
> > > >
> > > > I tried letting the board fully cool before placing it into COLD water,
> > as
> > > > I've seen suggested, and found that there was virtually no toner
> > transfer
> > > > whatsoever.
> > > >
> > > > Any tips or ideas?
> > > >
> > > >
> > > >
> > >
> > >
> > > [Non-text portions of this message have been removed]
> > >
> >
> >
> >
>
>
> [Non-text portions of this message have been removed]
>