Homebrew PCBs

From: "dkesterline" 
2. Re: PCB Electroplating
From: mpdickens 
3. Re: Toner transfer
From: "Steve" 
4. Two side alignment idea..
From: "javaguy11111" 
5. Re: PCB Electroplating
From: Adam Seychell 
6. Re: How to cut circuit boards? small correction
From: "mikezcnc" 
7. Re: Re: How to cut circuit boards? small correction
From: "Leon Heller" 
8. RE: Re: Toner transfer
From: "Pedro Perez de Ayala Rull" 

9. Layout considerations - BIG PADS!
From: Stefan Trethan 
10. Re: Layout considerations - BIG PADS!
From: "Leon Heller" 
11. Through Hole microscope
From: Balan 
12. Re: Layout considerations - BIG PADS!
From: Stefan Trethan 
13. Re: Two side alignment idea..
From: "Ben H. Lanmon" 
14. Re: Through Hole microscope
From: "DHC" 
15. Re: Through Hole microscope
From: "Dave Mucha" 
16. Re: Through Hole microscope
From: Adam Seychell 
17. Re: Through Hole microscope
From: Russell Shaw 
18. Breaking drill bits
From: "javaguy11111" 
19. Re: Two side alignment idea..
From: "javaguy11111" 
20. RE: Layout considerations - BIG PADS!
From: "Pedro Perez de Ayala Rull" 

21. Re: Breaking drill bits
From: JanRwl@...


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________________________________________________________________________

Message: 1
Date: Mon, 29 Dec 2003 03:28:06 -0000
From: "dkesterline" 
Subject: Re: Etchant recycling

Everyday Iron nails, polyethelene container, and the wires weren't in 
the solution.

Trick is the coper was on the negative nail, and was just powdery 
sludge. I'm no chemist either, but it didn't look like any 
electroplating I've ever seen. Besides, I thought the coper should 
plate onto the positive electrode?

-Denny


--- In Homebrew_PCBs@yahoogroups.com, "felixdkat2002" 
wrote:
> not sure what material your electrode needed to be made out of,
> but there are MANY different kinds of nails.... i would advise to 
> find your source on the proper electrode and then get a nail that 
> matches as closely as possible... if you got some copper on the 
one 
> nail it sounds like your idea was working, but you may have been 
> depositing other chemicals into your etching solution depending 
upon 
> what the container, wires, and nails were actually made of...
> 
> im not a chemist, but i know that these are all factors to 
> consider....
> 
> 
> 
> --- In Homebrew_PCBs@yahoogroups.com, "dkesterline" 
> wrote:
> > Hello,
> > 
> > I've been experimenting with toner transfer for a while now, and 
> I'm 
> > starting to see acceptable results. This group has been a great 
> help 
> > in my endevors.
> > 
> > I read some posts in the archives about recycling (revitalizing 
> might 
> > be a better word) Feric Chloride etchant.
> > 
> > As I read the instructions, using two iron nails as electrodes, 
> run 
> > about 1 amp through the solution. (more details would have been 
> > helpfull)
> > 
> > I tried this and my results were less than stellar. The negative 
> > terminal collected particulate copper (kinda looked like a 
sponge, 
> > but just dust, wiped off easily) and the negative terminal did 
> erode 
> > some (about 1 hour). In the end my etchant looked like brown mud. 
> > Then I tried etching with it and it seemed slower than before I 
> did 
> > it.
> > 
> > Perhaps sombody could advise?
> > 
> > Thanks,
> > Denny



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Message: 2
Date: Sun, 28 Dec 2003 19:37:28 -0800 (PST)
From: mpdickens 
Subject: Re: PCB Electroplating

As far as I remember, You should be able to plate directly onto the copper. 
However, I think Adam Seyshell is more qualified than me to definitively
answer this question. Why would you be interested in Au plating your pcb?
Are you having timing problems that are related to the resistance of the 
copper or the?

Best regards


Marvin Dickens
Alpharetta, Georgia USA

Udara Dewamuni wrote:
Hi There,

I am gonna gold plate my pcb. But i wanna
know in which plating should i do before do the gold
plating. I mean nickle plating or tin plating? What u
guys suggest?

Cheers,
Udara


Registered Linux User No. 80253
If you use linux, get counted at: 
http://www.linuxcounter.org

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[Non-text portions of this message have been removed]



________________________________________________________________________
________________________________________________________________________

Message: 3
Date: Mon, 29 Dec 2003 04:16:51 -0000
From: "Steve" 
Subject: Re: Toner transfer

They're beautiful, but- no one but you and I, the moderator, can see
the huge files you uploaded. The Photos section resizes everything
down to 300x400, that is all anyone else can see.

If I could get rid of the Photos section of the list, I would, but
there doesn't seem to be any provision for it.

This is why I prefer and recommend the Files section.

Steve

--- In Homebrew_PCBs@yahoogroups.com, "Pedro Perez de Ayala Rull"

wrote:
> 
> Hi all, once again I'm a little bit late... I posted a message
some time
> ago, talking about my experience with toner transfer. I'll briefly
say that
> I have been doing 8mil wide traces with 8mil clearance boards with
very few
> problems using an HP 1010 laser printer, a DSC laminator and Time
magazine
> paper. Some people asked if I could upload some pictures; I have
added them
> to the photos section, in the directory called "TT 8mil" there is one
> picture of a test that I did wich I cannot tell exact traces width, but
> those two traces going between 0.1 mil spaced pads is pretty much
> self-explainatory. The other two pictures are form a part of a 5 by
6 inch
> board that I am working on, I only showed a part of the board to
show it in
> detail but the whole board had no errors, the only errors I have
right now
> is aligning both sides of the board and drilling accurately, as you
can see
> in the etched picture.
> 
> Hope this helps someone, since I had to make many trials to achieve
> these results and would like this info to be useful.
> 
> Thank you all for this wonderful group!!,
> Pedro
]



________________________________________________________________________
________________________________________________________________________

Message: 4
Date: Mon, 29 Dec 2003 04:45:44 -0000
From: "javaguy11111" 
Subject: Two side alignment idea..

I am wondering if there may be some way to use mirrors to view both
sides of a circuit board at the same time as an aid to aligning
circuit traces. I am thinking something like an old stereo photo
viewer. Basically each side of the board shows in each eye and the
second side adjusted until the holes line up.

Alternatively maybe two digital cameras could be used and the images
superimposed on a monitor.

There may be a tool that does something like this, but I could find
nothing on google. I probably was not using the correct terminology.



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________________________________________________________________________

Message: 5
Date: Mon, 29 Dec 2003 16:24:58 +1100
From: Adam Seychell 
Subject: Re: PCB Electroplating

Nickel is normally used as a barrier layer between copper and 
gold. Tin will only cause copper migration into the gold over 
time. Well that's what the experts say anyway.

Adam

Udara Dewamuni wrote:
> Hi There,
> 
> I am gonna gold plate my pcb. But i wanna
> know in which plating should i do before do the gold
> plating. I mean nickle plating or tin plating? What u
> guys suggest?
> 
> Cheers,
> Udara
> 



________________________________________________________________________
________________________________________________________________________

Message: 6
Date: Mon, 29 Dec 2003 11:20:21 -0000
From: "mikezcnc" 
Subject: Re: How to cut circuit boards? small correction

Stefan,

This is the cutter that feeds the board between two rollers and cuts 
it while feeding the board. Very unusual but works like a dream. Mike

--- In Homebrew_PCBs@yahoogroups.com, Stefan Trethan 
wrote:
> On Sun, 28 Dec 2003 06:02:45 -0000, mikezcnc wrote:
> 
> > The said shears cut wonderfully a regular fiberglass board. 
however, I 
> > just learned that a Radio Shack-type Prottype Board gets crack 
terribly.
> 
> 
> Do you have a shear which slides down a blade simultaneously the 
whole 
> length?
> or do you have shear which pivots the blade down?
> Or have i not read wrong and you mentioned a roller?
> 
> ST



________________________________________________________________________
________________________________________________________________________

Message: 7
Date: Mon, 29 Dec 2003 11:29:07 -0000
From: "Leon Heller" 
Subject: Re: Re: How to cut circuit boards? small correction


----- Original Message ----- 
From: "mikezcnc" 
To: 
Sent: Monday, December 29, 2003 11:20 AM
Subject: [Homebrew_PCBs] Re: How to cut circuit boards? small correction


> Stefan,
>
> This is the cutter that feeds the board between two rollers and cuts
> it while feeding the board. Very unusual but works like a dream. Mike
>
> --- In Homebrew_PCBs@yahoogroups.com, Stefan Trethan
> wrote:
> > On Sun, 28 Dec 2003 06:02:45 -0000, mikezcnc wrote:
> >
> > > The said shears cut wonderfully a regular fiberglass board.
> however, I
> > > just learned that a Radio Shack-type Prottype Board gets crack
> terribly.

IIRC SRBP board shears properly if it is heated first. This softens the
resin.

Leon
--
Leon Heller, G1HSM
Email: aqzf13@...
My low-cost Philips LPC210x ARM development system:
http://www.geocities.com/leon_heller/lpc2104.html


________________________________________________________________________
________________________________________________________________________

Message: 8
Date: Mon, 29 Dec 2003 12:34:20 +0100
From: "Pedro Perez de Ayala Rull" 

Subject: RE: Re: Toner transfer


Ok, thanks Steve, I remembered there was some problems with the images
but didn't know what it was exactly. I have created a folder named "TT 8mil"
in the files section, the full sized pictures are in there. Hope it works
now ;-),

Pedro
-----Mensaje original-----
De: Steve [mailto:alienrelics@...]
Enviado el: lunes, 29 de diciembre de 2003 5:17
Para: Homebrew_PCBs@yahoogroups.com
Asunto: [Homebrew_PCBs] Re: Toner transfer


They're beautiful, but- no one but you and I, the moderator, can see
the huge files you uploaded. The Photos section resizes everything
down to 300x400, that is all anyone else can see.

If I could get rid of the Photos section of the list, I would, but
there doesn't seem to be any provision for it.

This is why I prefer and recommend the Files section.

Steve

--- In Homebrew_PCBs@yahoogroups.com, "Pedro Perez de Ayala Rull"

wrote:
>
> Hi all, once again I'm a little bit late... I posted a message
some time
> ago, talking about my experience with toner transfer. I'll briefly
say that
> I have been doing 8mil wide traces with 8mil clearance boards with
very few
> problems using an HP 1010 laser printer, a DSC laminator and Time
magazine
> paper. Some people asked if I could upload some pictures; I have
added them
> to the photos section, in the directory called "TT 8mil" there is one
> picture of a test that I did wich I cannot tell exact traces width, but
> those two traces going between 0.1 mil spaced pads is pretty much
> self-explainatory. The other two pictures are form a part of a 5 by
6 inch
> board that I am working on, I only showed a part of the board to
show it in
> detail but the whole board had no errors, the only errors I have
right now
> is aligning both sides of the board and drilling accurately, as you
can see
> in the etched picture.
>
> Hope this helps someone, since I had to make many trials to achieve
> these results and would like this info to be useful.
>
> Thank you all for this wonderful group!!,
> Pedro
]



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________________________________________________________________________
________________________________________________________________________

Message: 9
Date: Mon, 29 Dec 2003 13:02:34 +0100
From: Stefan Trethan 
Subject: Layout considerations - BIG PADS!

Hi all.

I just want to throw in (again) the following:

If you make boards with no through hole plating YOU NEED BIGGER PADS.
The layout software standard pads are for plated holes, where the pad can't 
lift off
that easy.

I made that mistake in the past too, since i enlarged my pads
the quality of the pcbs is much better.

The photos of Pedro reminded me of that.
(Great quality of TT Pedro but it would look much better with larger pads 
that don't lift off.
My TT is still a bit less quality, i hope i get it up to your standards.)


The function of the pad is not only for electrical contact, but also 
mechanical mounting
of that component. Keep that in mind.
A big pad also allows for some offset with two layer boards.

I use mostly oblong pads. they still allow 1 or 2 tracks between DIL ic 
pins. But they are long enough to provide some support.

There is this saying amongst pilots, "nothin' more useless to a pilot than 
air above
you an' runway behind you" (or similar).
For a pcb designer nothing is more useless than free pcb space beside a 
lift-off pad rim.


As said, the larger pads were a great improvement for me - therefore i want 
to share the thought.
Please don't mistake it as an offence to any of your designs.

Stefan









________________________________________________________________________
________________________________________________________________________

Message: 10
Date: Mon, 29 Dec 2003 12:14:28 -0000
From: "Leon Heller" 
Subject: Re: Layout considerations - BIG PADS!


----- Original Message ----- 
From: "Stefan Trethan" 
To: 
Sent: Monday, December 29, 2003 12:02 PM
Subject: [Homebrew_PCBs] Layout considerations - BIG PADS!


> Hi all.
>
> I just want to throw in (again) the following:
>
> If you make boards with no through hole plating YOU NEED BIGGER PADS.
> The layout software standard pads are for plated holes, where the pad
can't
> lift off
> that easy.

I have some special footprints I use for my home-made PCBs with larger pads
(identified with (SS) for single-sided), and a special Technology file for
tracks, vias etc.

Leon
--
Leon Heller, G1HSM
Email: aqzf13@...
My low-cost Philips LPC210x ARM development system:
http://www.geocities.com/leon_heller/lpc2104.html


________________________________________________________________________
________________________________________________________________________

Message: 11
Date: Mon, 29 Dec 2003 05:05:45 -0800 (PST)
From: Balan 
Subject: Through Hole microscope

Hi

I was looking for a through hole micro scope that can be used to examine the walls of a drilled hole after plating and also to examine the exposed rings in a multilayer pcb. I found one at this website http://www.startinternational.com/pdf/Optical/31a_OPGCP875.pdf but it is expensive. Does anyone know where i can get a similar instrument at a cheaper rate? Is there any similar instrument?

Balan





[Non-text portions of this message have been removed]



________________________________________________________________________
________________________________________________________________________

Message: 12
Date: Mon, 29 Dec 2003 15:53:59 +0100
From: Stefan Trethan 
Subject: Re: Layout considerations - BIG PADS!


> I have some special footprints I use for my home-made PCBs with larger 
> pads
> (identified with (SS) for single-sided), and a special Technology file 
> for
> tracks, vias etc.
>
> Leon
> --
> Leon Heller, G1HSM
> Email: aqzf13@...
> My low-cost Philips LPC210x ARM development system:
> http://www.geocities.com/leon_heller/lpc2104.html
>

I too.
It is worth the effort.
I create/modify the footprints as i need them in a design.

I still don't use/understand the technology files.
I think i really should read the help.
Most time i do hand routing (and always hand placing).
I check my designs myself for errors (drc disabled most time).
Maybe for preofessional pcbs it it more important...

ST


________________________________________________________________________
________________________________________________________________________

Message: 13
Date: Mon, 29 Dec 2003 15:35:21 -0000
From: "Ben H. Lanmon" 
Subject: Re: Two side alignment idea..

--- In Homebrew_PCBs@yahoogroups.com, "javaguy11111" 
wrote:
> I am wondering if there may be some way to use mirrors to view both
> sides of a circuit board at the same time as an aid to aligning
> circuit traces. 


The best way I know of is to do alignment holes in your patterns 
that match on both top and bottom then match these holes in the 
board then pin thru both pattern and the board to hold them 
together. 

Now if you are doing Toner Transfer not sure how that will work with 
it pined together with whatever heating method you use, as I do 
postive exposure with Transparencies. 


Ben



________________________________________________________________________
________________________________________________________________________

Message: 14
Date: Tue, 30 Dec 2003 09:50:50 +1100
From: "DHC" 
Subject: Re: Through Hole microscope

Hi,
If you want something really cheap then have a look at:
http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&product%5Fid=63-1133

I have an older model and it is very fiddly to use. Probably not the quality and performance you are after.

Cheers,
Darcy
----- Original Message ----- 
From: Balan 
To: Homebrew_PCBs@yahoogroups.com 
Sent: Tuesday, December 30, 2003 12:05 AM
Subject: [Homebrew_PCBs] Through Hole microscope


Hi

I was looking for a through hole micro scope that can be used to examine the walls of a drilled hole after plating and also to examine the exposed rings in a multilayer pcb. I found one at this website http://www.startinternational.com/pdf/Optical/31a_OPGCP875.pdf but it is expensive. Does anyone know where i can get a similar instrument at a cheaper rate? Is there any similar instrument?

Balan





[Non-text portions of this message have been removed]



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________________________________________________________________________
________________________________________________________________________

Message: 15
Date: Mon, 29 Dec 2003 23:21:03 -0000
From: "Dave Mucha" 
Subject: Re: Through Hole microscope


Check out the Intel Qx3 digital microscope and it's competitor.

These use your monitor as the display so you can 'keep looking up' 
and still see the action.

Seems they are going around $50.00 or so.


Can you let us know why this is a good idea ?

Dave





--- In Homebrew_PCBs@yahoogroups.com, "DHC" wrote:
> Hi,
> If you want something really cheap then have a look at:
> http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&product%
5Fid=63-1133
> 
> I have an older model and it is very fiddly to use. Probably 
not the quality and performance you are after.
> 
> Cheers,
> Darcy
> ----- Original Message ----- 
> From: Balan 
> To: Homebrew_PCBs@yahoogroups.com 
> Sent: Tuesday, December 30, 2003 12:05 AM
> Subject: [Homebrew_PCBs] Through Hole microscope
> 
> 
> Hi
> 
> I was looking for a through hole micro scope that can be used to 
examine the walls of a drilled hole after plating and also to examine 
the exposed rings in a multilayer pcb. I found one at this website 
http://www.startinternational.com/pdf/Optical/31a_OPGCP875.pdf but it 
is expensive. Does anyone know where i can get a similar instrument 
at a cheaper rate? Is there any similar instrument?
> 
> Balan
> 
> 
> 
> 
> 
> [Non-text portions of this message have been removed]
> 
> 
> 
> Be sure to visit the group home and check for new Bookmarks and 
files:
> http://groups.yahoo.com/group/Homebrew_PCBs 
> 
> 
> 
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________________________________________________________________________
________________________________________________________________________

Message: 16
Date: Tue, 30 Dec 2003 10:28:24 +1100
From: Adam Seychell 
Subject: Re: Through Hole microscope

Balan, are you a home brewer doing plated through hole ?
Not many are going to this level so I was curious what your 
accomplishments are.

The microscope you mentioned sounds kind of specialized. I don't 
think you will find something similar, unless of course you know 
how the optics function in the device, and look for low cost mass 
produced item with similar optical arrangement that's designed 
for another purpose. What was the price for the through hole 
microscope ?

Adam

Balan wrote:
> Hi
> 
> I was looking for a through hole micro scope that can be used to examine the walls of a drilled hole after plating and also to examine the exposed rings in a multilayer pcb. I found one at this website http://www.startinternational.com/pdf/Optical/31a_OPGCP875.pdf but it is expensive. Does anyone know where i can get a similar instrument at a cheaper rate? Is there any similar instrument?
> 
> Balan
> 
> 
> 
> 
> 



________________________________________________________________________
________________________________________________________________________

Message: 17
Date: Tue, 30 Dec 2003 11:30:43 +1100
From: Russell Shaw 
Subject: Re: Through Hole microscope

Adam Seychell wrote:
> Balan, are you a home brewer doing plated through hole ?
> Not many are going to this level so I was curious what your 
> accomplishments are.
> 
> The microscope you mentioned sounds kind of specialized. I don't 
> think you will find something similar, unless of course you know 
> how the optics function in the device, and look for low cost mass 
> produced item with similar optical arrangement that's designed 
> for another purpose. What was the price for the through hole 
> microscope ?
> 
> Adam
> 
> Balan wrote:
> 
>>Hi
>> 
>> I was looking for a through hole micro scope that can be used to examine the walls of a drilled hole after plating and also to examine the exposed rings in a multilayer pcb. I found one at this website http://www.startinternational.com/pdf/Optical/31a_OPGCP875.pdf but it is expensive. Does anyone know where i can get a similar instrument at a cheaper rate? Is there any similar instrument?

Another way is to saw the board near a hole with a fine
saw, polish up the cross-sectional cut on a belt or disc
sander, then use a conventional microscope.



________________________________________________________________________
________________________________________________________________________

Message: 18
Date: Tue, 30 Dec 2003 01:16:07 -0000
From: "javaguy11111" 
Subject: Breaking drill bits

I just got a set of resharpened carbide bits in from drill city. I
chuck one up into my dremel press. I snap the bit on the first hole.
Thinking maybe I moved the board, I tried a second bit and snapped it
as well. This was with a #81 bit. So I thought maybe I am just a
little clumsy and try a 1/32 bit and snap it. Noticeing that the bit
did not penetrate all the way, I thought maybe I needed a backer.
Still no success and I snap another 1/32 bit.

My guess is that the dremel just has too much slop for these bits. Any
suggestions. 



________________________________________________________________________
________________________________________________________________________

Message: 19
Date: Tue, 30 Dec 2003 01:19:30 -0000
From: "javaguy11111" 
Subject: Re: Two side alignment idea..

I am trying to line up press and peel. I have done one two sided board
just lining up and taping. That worked, but I am going to be doing
much smaller holes and I think I am going to have problems maintaining
alignment so I was trying to think of other ways to make sure things
line up.



--- In Homebrew_PCBs@yahoogroups.com, "Ben H. Lanmon" 
wrote:
> --- In Homebrew_PCBs@yahoogroups.com, "javaguy11111" 
> wrote:
> > I am wondering if there may be some way to use mirrors to view
both
> > sides of a circuit board at the same time as an aid to aligning
> > circuit traces. 
> 
> 
> The best way I know of is to do alignment holes in your patterns 
> that match on both top and bottom then match these holes in the 
> board then pin thru both pattern and the board to hold them 
> together. 
> 
> Now if you are doing Toner Transfer not sure how that will work
with 
> it pined together with whatever heating method you use, as I do 
> postive exposure with Transparencies. 
> 
> 
> Ben



________________________________________________________________________
________________________________________________________________________

Message: 20
Date: Tue, 30 Dec 2003 02:25:55 +0100
From: "Pedro Perez de Ayala Rull" 

Subject: RE: Layout considerations - BIG PADS!


Yes, I totally agree with you. This board had to be aligned with very
special care for that reason, the small via size was an error(I learned that
in the drilling phase...). I think it is a valuable advice to keep in mind.

Pedro

-----Mensaje original-----
De: Stefan Trethan [mailto:stefan_trethan@...]
Enviado el: lunes, 29 de diciembre de 2003 13:03
Para: homebrew_pcbs@yahoogroups.com
Asunto: [Homebrew_PCBs] Layout considerations - BIG PADS!


Hi all.

I just want to throw in (again) the following:

If you make boards with no through hole plating YOU NEED BIGGER PADS.
The layout software standard pads are for plated holes, where the pad can't
lift off
that easy.

I made that mistake in the past too, since i enlarged my pads
the quality of the pcbs is much better.

The photos of Pedro reminded me of that.
(Great quality of TT Pedro but it would look much better with larger pads
that don't lift off.
My TT is still a bit less quality, i hope i get it up to your standards.)


The function of the pad is not only for electrical contact, but also
mechanical mounting
of that component. Keep that in mind.
A big pad also allows for some offset with two layer boards.

I use mostly oblong pads. they still allow 1 or 2 tracks between DIL ic
pins. But they are long enough to provide some support.

There is this saying amongst pilots, "nothin' more useless to a pilot than
air above
you an' runway behind you" (or similar).
For a pcb designer nothing is more useless than free pcb space beside a
lift-off pad rim.


As said, the larger pads were a great improvement for me - therefore i want
to share the thought.
Please don't mistake it as an offence to any of your designs.

Stefan








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To visit your group on the web, go to:
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________________________________________________________________________
________________________________________________________________________

Message: 21
Date: Mon, 29 Dec 2003 20:47:18 EST
From: JanRwl@...
Subject: Re: Breaking drill bits

In a message dated 12/29/2003 7:19:07 PM Central Standard Time, 
javaguy11111@... writes:
My guess is that the dremel just has too much slop for these bits. Any
suggestions.
The two Dremels I have tried have run-out enough to break a sturdy 1/8" bit! 
Just NOT the machine for this application! A plain ol' "machinist's" 1/2" 
chuck drill-press is more precise!

There are precision quill-motors, both high-freq. 3-phase and "air" which 
will do the job (NSK comes to mind), but I guess $400 is more budget than a $90 
Dremel (worth $12.95 on a good day!)...

Lotsa luck!


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