Blue transfer paper

This is the place for any magazine-related discussions that don't fit in any of the column discussion boards below.
User avatar
MrAl
Posts: 3862
Joined: Fri Jan 11, 2002 1:01 am
Location: NewJersey
Contact:

Blue transfer paper

Post by MrAl » Sat Apr 19, 2008 3:23 am

Hi there,

I recently tried the blue transfer paper to get a circuit board
layout from a laser printout and have very limited success so far.

I had the iron on highest setting and left for 3 minutes, 5 mins,
and 9 minutes and had somewhat bad results.

Part of the circuit transfers and part of it doesnt.
For example, one large pad was almost completely missing
and several traces not that thin were broken with gaps as large
as 1/16 inch.

Any ideas?

I see raves all over the web about this stuff.

Thanks much.
LEDs vs Bulbs, LEDs are winning.

Engineer1138
Posts: 458
Joined: Thu Feb 05, 2004 1:01 am
Location: Minneapolis, MN
Contact:

Post by Engineer1138 » Sat Apr 19, 2008 11:25 am

I have tried it before a few times and all but given up. I actually have a board I printed out a few days ago on toner transfer paper that I haven't gotten around to transferring yet. If this fails, it's back to photosensitive PCB!

However, I have been told that using fine sandpaper/brillo pad makes a big difference. I normally clean the surface with a degreaser, but never tried sanding it.

I will try ironing my board later today and report back if sanding the copper made any difference.

L. Daniel Rosa
Posts: 400
Joined: Tue Dec 25, 2001 1:01 am
Location: Bellingham, WA
Contact:

Post by L. Daniel Rosa » Sat Apr 19, 2008 11:51 am

Surface preparation is _everything_. Wash the sink thoroughly. Use dish detergent with no moisturizers or lotions, preferably no perfumes either. Use hot water and a new scotch pad, with no sponge/cleanser/powdery junk attached- just a plain scrubby.

Lightly scrub lengthwise, then crosswise. You're not only cleaning and degreasing the surface, you're also scraping off oxides and increasing the surface area (and improving adhesion) by a factor of two to ten.

Rinse with hot water and dry under a heat lamp

Dean Huster
Posts: 1263
Joined: Wed Dec 05, 2001 1:01 am
Location: Harviell, MO (Poplar Bluff area)
Contact:

Post by Dean Huster » Sat Apr 19, 2008 12:29 pm

I agree with L. Dan. I use Comet cleanser for the detergent. The 3M Scotch-Brite (accept no substitutes) treatment gives "tooth" to the board as well as giving it a good cleaning. Some folks have even been known to dip the board into etchant for half a minute in addition. I've done that, but find that it ends up being a messy and unnecessary step.

Handle the clean board ONLY BY THE EDGES. No amount of hand scrubbing will render your fingers clean enough to touch the surface of the board.

I have never had any luck with using a clothing iron. Today's irons don't get as hot as those made in 1955. I've had the best success when using a photographic drymount press on its highest setting. It has a big, flat surface, lots of heat retention and UNIFORMITY over the whole board area. I would assume that a T-shirt decal press will also work well.

Press 'n' Peel works well if you take the proper steps.

Dean
Dean Huster, Electronics Curmudgeon
Contributing Editor emeritus, "Q & A", of the former "Poptronics" magazine (formerly "Popular Electronics" and "Electronics Now" magazines).

R.I.P.

User avatar
philba
Posts: 2050
Joined: Tue Nov 30, 2004 1:01 am
Location: Seattle
Contact:

Post by philba » Sat Apr 19, 2008 12:30 pm

agreed - surface prep is, indeed, everything. I do all that plus I wipe the board down with acetone.

I wonder if you aren't using enough pressure.

I tried it with ok results but toner transfer is pretty easy to master and a lot cheaper.

User avatar
MrAl
Posts: 3862
Joined: Fri Jan 11, 2002 1:01 am
Location: NewJersey
Contact:

Post by MrAl » Sat Apr 19, 2008 9:34 pm

Hi again,


Thanks for the ideas and suggestions.

I did clean the board very well with running water and brillo.
I do that when i use a marker to draw the pattern too and it
works very well.

I am now wondering if the board imperfections could play a role
in this process, such as if the board surface is not perfectly smooth.
An inspection of the surface reveals some ups and downs, where
the copper covered the glass fibers. The glass fibers are visible
somewhat, which tells me that the copper clad top surface is
not perfectly smooth, but goes up and down with the glass weave
pattern underneath.

Maybe smoother PC boards would work? Anyone ever have this
problem with the unsmooth surface?

Here's a close up of the computer drawing vs the actual board after
the transfer...



Image


I also hear that ordinary photo paper (glossy) works too but you
have to soak the board to get the backing off.
Anyone try this?
LEDs vs Bulbs, LEDs are winning.

Robert Reed
Posts: 2276
Joined: Wed Nov 24, 2004 1:01 am
Location: ASHTABULA,OHIO
Contact:

Post by Robert Reed » Sun Apr 20, 2008 8:45 am

MrAl
"I did clean the board very well with running water and brillo.
I do that when i use a marker to draw the pattern too and it
works very well. "

Don't know if that would add to your woes, But BRILLO PADS have a waxing substance in them along with the soapy substance. This is what gives whatever you clean that nice satin sheen. But in your case that coating may have to be removed with a couple of swipes of acetone before proceeding further.

User avatar
philba
Posts: 2050
Joined: Tue Nov 30, 2004 1:01 am
Location: Seattle
Contact:

Post by philba » Sun Apr 20, 2008 10:01 am

There are 2 things you need: a clean, grease free surface and heat+pressure. You could try wet-n-dry 600 grit paper with an acetone wash. This creates an "activated" surface and removes oil and grease. The 600 grit will create a lot more surface area for the resist to adhere to. You will be able to see the FR4 fiber pattern in the copper, that's common. The resist will conform to an uneven surface. The temperature needs to be high enough. If your iron isn't hot enough you will have poor adherence. If you don't provide enough pressure you will have the same problem.

The photo paper approach is called toner transfer and you will find a ton of hits on it in google. Basically, any coated paper will work for TT - you just have to find the right technique (soaking, light scrubbing). I personally use inkjet paper in a laser printer. Magazine paper works as does photo paper. I don't use photo paper because it's hard to align the artwork when doing double sided PCBs.

Dean Huster
Posts: 1263
Joined: Wed Dec 05, 2001 1:01 am
Location: Harviell, MO (Poplar Bluff area)
Contact:

Post by Dean Huster » Sun Apr 20, 2008 1:05 pm

TOO much pressure will cause the toner to squish and you'll end up with all your IC pins shorted together. Toner squish was my biggest problem using a clothing iron.

Dean
Dean Huster, Electronics Curmudgeon
Contributing Editor emeritus, "Q & A", of the former "Poptronics" magazine (formerly "Popular Electronics" and "Electronics Now" magazines).

R.I.P.

User avatar
MrAl
Posts: 3862
Joined: Fri Jan 11, 2002 1:01 am
Location: NewJersey
Contact:

Post by MrAl » Sun Apr 20, 2008 11:12 pm

Hi again,


Robert:
Hmmm, that's interesting. How do you know brillo contains wax?

philba:
I'll have to try the sandpaper then, sounds good.
I guess the glass weave pattern is typical then, and it
should still work ok so something else must not be right.
Im wondering if the iron is hot enough. It's brand new but
it's a cheapie (10 USD).
What do you mean inkjet paper? Is that glossy or not?

Dean:
I dont think i have the pressure problem as i dont apply too
much pressure, just about 5 pounds per square inch.


ALL:
Do you all use a sheet of paper between the iron and the blue paper?
Maybe that is causing too much loss of heat?
Would the iron melt the blue paper if touched directly?
LEDs vs Bulbs, LEDs are winning.

amelecsol2000

Blue transfer

Post by amelecsol2000 » Mon Apr 21, 2008 2:56 am

I have had some good results with this press & peel but only on smaller boards. I have tried to do pcb's 7" X 10" and get some sad results. I use paper in between the iron and press & peel.
I even did a 2 sided board that came out ok but it was still a 3" X 4" board.
It was a waste of money so far purchasing their big iron. No matter what I did the larger boards wrinkled.

User avatar
MrAl
Posts: 3862
Joined: Fri Jan 11, 2002 1:01 am
Location: NewJersey
Contact:

Post by MrAl » Mon Apr 21, 2008 6:42 am

Hello amelecsol2000,

That's interesting.
What do you mean by 'wrinkled' though? The whole sheet?
LEDs vs Bulbs, LEDs are winning.

FOB
Posts: 15
Joined: Thu Nov 29, 2007 9:54 am
Location: Eastern Iowa
Contact:

PC Transfers

Post by FOB » Mon Apr 21, 2008 9:22 am

Unless it absolutely has to be pretty, why use the computer printout? You could probably draw it up with a sharpie pen in less than 15 minutes. Make a copy of the foil side, tape it to the foil side of the board, drill the holes, connect the holes with sharpie, go over it again after it dries. If you really want to avoid uneven etching, go over the sharpie with a fine paintbrush and cheap enamel paint, clean it up with a xacto knife and etch. Heat your ferric chloride up to about 105 deg. F. use an old tupperware dish pour about 1/2 inch liquid over the board and roll it back and forth keeping the liquid moving. It will be done in about 5 minutes. Then wash it clean in water. Just one opinion.
...Bob...

amelecsol2000

Blue transfer

Post by amelecsol2000 » Mon Apr 21, 2008 5:26 pm

Hello Mr. Al and everyone else,
Worker with the larger boards, the center of the transfer came out fine but all of the outer edges curled up and smeared the pattern. Tried it a couple of times with no better results.

What FOB recomends is what I do for the larger boards for now. Eagle crames a lot of components in a small space and it looks good when it is done. It is also much less time consuming then doing it all by hand.

User avatar
philba
Posts: 2050
Joined: Tue Nov 30, 2004 1:01 am
Location: Seattle
Contact:

Post by philba » Mon Apr 21, 2008 6:40 pm

What do you mean inkjet paper? Is that glossy or not?
no, it's not glossy. Just regular inkjet paper. ~$4 a ream. It is coated to prevent the inkjet ink from bleeding though you can't tell by looking at it.

By the way, I agree with others that say using an iron is problematic. I bought a hot laminator and modified it to allow the thicker boards to pass through. That gave me more even results. still, as long as you maintain pressure and heat, the iron will work.

Post Reply

Who is online

Users browsing this forum: No registered users and 45 guests