Homebrew_PCBs

Hi all,

As a total n00b to homebrew PCBs, I've been struggling for the last
couple of weeks to get artwork onto the copper intact.

I must have made 20 or more attempts with the clothes iron, each time
getting most of the toner onto the board, but missing entire areas, with
intricate traces too fine for touching up by hand with the etch resist pen.

Also made a few failed attempts with the special iron-on transfer film;
IMHO, that stuff is not worth the money.

But Lady Luck was kind to me today. I found a used working Ibico PL-260
laminator in a Cash Converters store for $35 (approx US$25)!
Four spring loaded rollers, 6 motor speeds, digital temp control, perfect.

So the approach that's working for me, /finally/, is:

1. laser-print onto HP Gloss Inkjet photo card

2. scrub board with green plastic kitchen scouring sponge

3. clean copper surface thoroughly with acetone (I used my
wife's nail polish remover)

4. 4 or so passes through laminator, with slowest motor speed, and
temperature set to 160degC on more - feeding in corner first

5. peeling the card off very slowly while board still hot, in a very
slow bending motion

(I could hold the edge of the card along a glass tumbler, or other
cylindrical object with 8cm or more diameter, and gently 'roll off'
the card around the tumbler, so as not to tear off huge chunks of
toner).

6. touch up artwork with etch resist pen (very few imperfections, so
this was quick and easy).

7. etch in warmed ferric chloride

8. gently remove toner with acetone, but only when ready to drill and
populate the board.

So to newcomers, I would strongly advise against the clothes iron
approach - unless you're lucky, and have a special 'feel', this will
likely drag you into a time-wasting world of pain.

Get a laminator - a decent one with spring-loaded rollers, speed and
temperature control. Either just find the money, or put the time/energy
into finding a cheap used one. You'll be glad you did, when you end up
with crisp, clear artwork on the copper.

For the experts here - if you can suggest any refinements, I'm all ears.

--
Cheers
David

On Wed, 08 Jun 2005 09:31:57 +0200, David McNab <david@...>
wrote:

>
> 3. clean copper surface thoroughly with acetone (I used my
> wife's nail polish remover)

I have heard stories they contaminate i badly with smelly stuff and other
things. When it works it's fine, but for a beginner it could be a
potential source of problem to use nail polish remover, as i'm sure not
all brands are the same.


ST

Thanks David, you have jogged my memory. Ibico is the up-market label used
by GBC in Australia. It uses GBC in the consumer, retail market.
Bill

----- Original Message -----
From: "David McNab" <david@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Wednesday, June 08, 2005 5:31 PM
Subject: [Homebrew_PCBs] Forget the clothes iron - get a laminator


> Hi all,
>
> As a total n00b to homebrew PCBs, I've been struggling for the last
> couple of weeks to get artwork onto the copper intact.
>
> I must have made 20 or more attempts with the clothes iron, each time
> getting most of the toner onto the board, but missing entire areas, with
> intricate traces too fine for touching up by hand with the etch resist
> pen.
>
> Also made a few failed attempts with the special iron-on transfer film;
> IMHO, that stuff is not worth the money.
>
> But Lady Luck was kind to me today. I found a used working Ibico PL-260
> laminator in a Cash Converters store for $35 (approx US$25)!
> Four spring loaded rollers, 6 motor speeds, digital temp control, perfect.
>
> So the approach that's working for me, /finally/, is:
>
> 1. laser-print onto HP Gloss Inkjet photo card
>
> 2. scrub board with green plastic kitchen scouring sponge
>
> 3. clean copper surface thoroughly with acetone (I used my
> wife's nail polish remover)
>
> 4. 4 or so passes through laminator, with slowest motor speed, and
> temperature set to 160degC on more - feeding in corner first
>
> 5. peeling the card off very slowly while board still hot, in a very
> slow bending motion
>
> (I could hold the edge of the card along a glass tumbler, or other
> cylindrical object with 8cm or more diameter, and gently 'roll off'
> the card around the tumbler, so as not to tear off huge chunks of
> toner).
>
> 6. touch up artwork with etch resist pen (very few imperfections, so
> this was quick and easy).
>
> 7. etch in warmed ferric chloride
>
> 8. gently remove toner with acetone, but only when ready to drill and
> populate the board.
>
> So to newcomers, I would strongly advise against the clothes iron
> approach - unless you're lucky, and have a special 'feel', this will
> likely drag you into a time-wasting world of pain.
>
> Get a laminator - a decent one with spring-loaded rollers, speed and
> temperature control. Either just find the money, or put the time/energy
> into finding a cheap used one. You'll be glad you did, when you end up
> with crisp, clear artwork on the copper.
>
> For the experts here - if you can suggest any refinements, I'm all ears.
>
> --
> Cheers
> David
>
>
>
> Be sure to visit the group home and check for new Links, Files, and
> Photos:
> http://groups.yahoo.com/group/Homebrew_PCBs
>
> If Files or Photos are running short of space, post them here:
> http://groups.yahoo.com/group/Homebrew_PCBs_Archives/
> Yahoo! Groups Links
>
>
>
>
>
>
>

Stefan Trethan wrote:

>>3. clean copper surface thoroughly with acetone (I used my
>> wife's nail polish remover)

> I have heard stories they contaminate i badly with smelly stuff and other
> things. When it works it's fine, but for a beginner it could be a
> potential source of problem to use nail polish remover, as i'm sure not
> all brands are the same.

Right you are.

Nail polish remover has oils added to nourish the nail.

Acetone is much better - I really should get some.

My wife's nail polish remover didn't seem to cause any problems though.

--
Cheers
David

In message <42A6D181.3050208@...>
David McNab <david@...> wrote:

> Acetone is much better - I really should get some.

The best thing I've used is 600-grit 3M "WetOrDry" silicon-carbide paper. Put
the board in a bowl full of water, then use the wet-dry paper to remove any
dirt on the board. Rub in two orthogonal directions, then lift the board out
of the water. If water beads up on the surface, give that area a bit more of
a scrub. When the board is perfectly clean, the water will form a
more-or-less solid "sheet" on the copper.

Takes about 10 minutes to do it properly, but it gets all the crap off. Same
trick works for removing the toner, though I sometimes use acetone for that.
Spray the board with flux after you've removed the toner.

I'm going to try and get hold of a pair of broken Laserjet III printers at
some point. Hopefully it shouldn't be too hard to build a controller for the
fuser. Need to get a thermocouple or a PT100 sensor first though (to set the
trip point on the temperature controller).

Just out of curiosity, what temperature are you guys running your fusers at?

Later.
--
Phil. | Acorn Risc PC600 Mk3, SA202, 64MB, 6GB,
philpem@... | ViewFinder, 10BaseT Ethernet, 2-slice,
http://www.philpem.me.uk/ | 48xCD, ARCINv6c IDE, SCSI
For sale: Minor planetoid. First person to land there gets ownership.

On Mon, 20 Jun 2005 10:05:08 +0200, Philip Pemberton
<philpem@...> wrote:

> The best thing I've used is 600-grit 3M "WetOrDry" silicon-carbide
> paper. Put
> the board in a bowl full of water, then use the wet-dry paper to remove
> any
> dirt on the board. Rub in two orthogonal directions, then lift the board
> out
> of the water. If water beads up on the surface, give that area a bit
> more of
> a scrub. When the board is perfectly clean, the water will form a
> more-or-less solid "sheet" on the copper.
> Takes about 10 minutes to do it properly, but it gets all the crap off.
> Same
> trick works for removing the toner, though I sometimes use acetone for
> that.
> Spray the board with flux after you've removed the toner.
> I'm going to try and get hold of a pair of broken Laserjet III printers
> at
> some point. Hopefully it shouldn't be too hard to build a controller for
> the
> fuser. Need to get a thermocouple or a PT100 sensor first though (to set
> the
> trip point on the temperature controller).
> Just out of curiosity, what temperature are you guys running your fusers
> at?
> Later.

I had expected it to be rather difficult to clean a board with water only
and paper, but it seems it isn't that hard (a bit time consuming tho.)

Anyway, if you want a "dry" approach dry sand the board with the paper,
and then wipe with acetone and a paper towel. The paper is quickly clogged
up in dry mode, but you only need small pieces and it's cheap. Takes less
than a minute. There's also 1000grit paper which gives a less scratched
finish.

I would use sanding sparingly, as the copper is very thin to start out
with. It isn't hard to sand it off at the edges. I usually just sand
enough to get sandmarks all over the board and not more.

For taking the toner off, i use a steel scraper. just scrape it off dry
and rinse with water. Works very well. Haven't managed to damage a track
yet, seems difficult. Acetone works but i don't see why i should waste it
if a mechanic approach is that easy.


The LJIII has the fuser unit easily removeable, and has a thermistor on it
as any fuser (still need meter for initial adjustment). There might even
be a triac on that small board on the side, not sure. I guess you would
need to get one of the gears out of the printer too, or find some other
way to drive it. I don't remember if it is easy to modify for thicker
material.


I'm running my fuser at 160C.


ST

On Mon, 20 Jun 2005 10:05:08 +0200, Philip Pemberton
<philpem@...> wrote:

> Just out of curiosity, what temperature are you guys running your fusers
> at?
> Later.

By the way, 160C is just below the point where copier paper will start to
brown, so you could use that to adjust.

ST

Refer to an earlier post, 7726, regarding measured laminator
temperature.

Lyman

I use a picture dry mount press, followed by an iron.
The dry mount press prevents any sliding of the paper on the PC board
during the initial heating, but is not really hot enough to do the
entire job. I then remove the board from the hot press and use an iron
on linen setting for 2 minutes to finish it. The iron provides more
heat to ensure large ground plane areas transfer without holes. YOu
know it's done when the waste sheet covering picture paper just
slightly starts getting brown.

The best paper by far for me is the "Staples Picture Paper, 30 sheets
for 10. item no. 471861 (details here) -

http://www.fullnet.com/u/tomg/gooteepc.htm

I let it soak for 5 mins then use a tooth brush to get it off. This is
by far the best technique for toner transfer I've used so far. I tried
label paper, etc. and this particular photo paper combined with
soaking removal works best for me.

-bob

--- In Homebrew_PCBs@yahoogroups.com, David McNab <david@r...> wrote:
> Hi all,
>
> As a total n00b to homebrew PCBs, I've been struggling for the last
> couple of weeks to get artwork onto the copper intact.

In message <op.ssntfm02mg0lsf@tu-x2pj5qeyp2u4>
"Stefan Trethan" <stefan_trethan@...> wrote:

> The LJIII has the fuser unit easily removeable,

You can say that again.. Four screws, then it lifts up and out. Very nice.
Check the continuity between the pins on the lamp connector before you buy
one though - replacing the thermofuse is very difficult, if not impossible.
It's even worse if the fuser lamp's burned out.

> and has a thermistor on it
> as any fuser (still need meter for initial adjustment). There might even
> be a triac on that small board on the side, not sure.

No - there's an optosensor; the triac is in the AC Power Unit (the thing
that takes the mains inlet connector). ISTR there's a 24V drive circuit for
the erase lamps, but that's it.

> I guess you would
> need to get one of the gears out of the printer too, or find some other
> way to drive it. I don't remember if it is easy to modify for thicker
> material.

It isn't too hard. Remove the front paper guide (2 screws) and the flip-down
guide at the back (2 more screws). The silver roller is the heated roller,
the red one is a rubber pressure roller. The big problem is that the fuser
feeds REALLY thick stuff (e.g. PCBs) at an angle of about 30 degrees, which
means the fuser needs mounting at an angle. I'll see if it does the same
thing with 0.8mm laminate in a bit, or if feeding from the back makes any
difference.

I need to glue a bit of the plastic on my fuser back together though - I
slipped and broke one of the mounting arms that holds the AC power connector.
Next job is to gut the AC power module and pray that the triac and
zero-crossing optotriac are intact.

Next job is to find a motor. Something that'll run the fuser so that the
board gets fed in at about 0.1ips.

> I'm running my fuser at 160C.

Exactly the same as the HP recommended temperature then. ISTR the LJ3
increases the fuser temp to 180C when it's working on thick media and the
thermofuse trips at 210C.

Later.
--
Phil. | Acorn Risc PC600 Mk3, SA202, 64MB, 6GB,
philpem@... | ViewFinder, 10BaseT Ethernet, 2-slice,
http://www.philpem.me.uk/ | 48xCD, ARCINv6c IDE, SCSI
... Live every day like it's your last, because someday you'll be right.

On Sat, 02 Jul 2005 12:45:44 +0200, Philip Pemberton
<philpem@...> wrote:

>
> You can say that again.. Four screws, then it lifts up and out. Very
> nice.
> Check the continuity between the pins on the lamp connector before you
> buy
> one though - replacing the thermofuse is very difficult, if not
> impossible.
> It's even worse if the fuser lamp's burned out.

I don't consider the thermofuse a problem, the LJIII has thermoswitch
though, which i have replaced on mine once (kapton tape rubbed through).
Also, i think for PCBs it would be acceptable to bridge the thermofuse.
Lamp must be good tho.

> No - there's an optosensor; the triac is in the AC Power Unit (the thing
> that takes the mains inlet connector). ISTR there's a 24V drive circuit
> for
> the erase lamps, but that's it.

I see. Yes, now i remember seeing the triac in the AC PU when repairing a
power problem.
Just remembered a small PCB on the fuser and thought it might be.

>
>> I guess you would
>> need to get one of the gears out of the printer too, or find some other
>> way to drive it. I don't remember if it is easy to modify for thicker
>> material.

> It isn't too hard. Remove the front paper guide (2 screws)

Really? Then i must have done something wrong - work on the front always
required me to take of about 15 screws (the whole front "panel" thing),
even for getting out the DC PSU. I thought that is the more nasty section
of the printer. Maybe i missed a easy way to do it.
But still - how many of todays printers still work if you remove ALL
plastic and a good deal of steel? If you take off a side-panel on a new
printer the unit usually falls apart into a thousand pieces.

> and the flip-down
> guide at the back (2 more screws). The silver roller is the heated
> roller,
> the red one is a rubber pressure roller. The big problem is that the
> fuser
> feeds REALLY thick stuff (e.g. PCBs) at an angle of about 30 degrees,
> which
> means the fuser needs mounting at an angle. I'll see if it does the same
> thing with 0.8mm laminate in a bit, or if feeding from the back makes any
> difference.

Maybe you can remove some guard? why is it feeding at such an odd angle.
(it sounds almost as if it is a sick animal..... ;-)

> I need to glue a bit of the plastic on my fuser back together though - I
> slipped and broke one of the mounting arms that holds the AC power
> connector.
> Next job is to gut the AC power module and pray that the triac and
> zero-crossing optotriac are intact.
> Next job is to find a motor. Something that'll run the fuser so that the
> board gets fed in at about 0.1ips.

Chicken grill motor ;-)

>
>> I'm running my fuser at 160C.
> Exactly the same as the HP recommended temperature then. ISTR the LJ3
> increases the fuser temp to 180C when it's working on thick media and the
> thermofuse trips at 210C.

My PCB fuser is from a ricoh copier, and it had "thermal cutoff 160°C"
written on top, so that's what i used.
The copier fusers often have a knob on the lower roller, which you can
turn by hand to remove a jam. Neat to override the drive motor. I don't
think i will ever use the LJIIID fuser for PCBs, 'cause that beast just
isn't going to die any time soon.

ST

In message <op.staas3yqmg0lsf@tu-x2pj5qeyp2u4>
"Stefan Trethan" <stefan_trethan@...> wrote:

> Also, i think for PCBs it would be acceptable to bridge the thermofuse.

Only if you don't mind causing a fire if/when the temperature controller jams
on :)

> Really? Then i must have done something wrong - work on the front always
> required me to take of about 15 screws (the whole front "panel" thing),
> even for getting out the DC PSU. I thought that is the more nasty section
> of the printer. Maybe i missed a easy way to do it.

ISTR you only need to open the flip-out section, then remove the four screws
that hold the fuser in place. I'm not 100% sure about that though - I'd need
to check the service manual.
Getting the top cover off is difficult, but it's worth it for the big, meaty
stepper motor. Shame it's got such an odd shaft shape though - sort of a
spiral. Never seen anything like it.

> But still - how many of todays printers still work if you remove ALL
> plastic and a good deal of steel? If you take off a side-panel on a new
> printer the unit usually falls apart into a thousand pieces.

:)

> Maybe you can remove some guard? why is it feeding at such an odd angle.
> (it sounds almost as if it is a sick animal..... ;-)

Dunno.. Might have something to do with trying to feed it 1.6mm PCB laminate.
Or the fact that the rollers are slightly offset from each other - the red
rubber roller is slightly further back inside the casing.

> Chicken grill motor ;-)

If I can find one.

Later.
--
Phil. | Acorn Risc PC600 Mk3, SA202, 64MB, 6GB,
philpem@... | ViewFinder, 10BaseT Ethernet, 2-slice,
http://www.philpem.me.uk/ | 48xCD, ARCINv6c IDE, SCSI
... Some people are, through no fault of their own, sane.