开云体育

If I had a design with hundreds of boards, or multilayer boards, or
even tens of through-holes on 4 or 5 boards, I think that I could
find better uses of my time than etching them "homebrew" style.
Homebrew is great for PROTO's and One-off's, where you would like
something in a couple of hours, but the personal economics quickly
get swamped.

At 12:05 PM 4/03/2002 EST, you wrote:

In a message dated 04-Mar-02 08:15:05 Central Standard Time,
j.walton@... writes:

Homebrew is great for PROTO's and One-off's, where you would like
something in a couple of hours, but the personal economics quickly
get swamped.

Exactly! The only things that would make PTH at home "worth it" would be

any

one or combination of the following:

1. The personal "need" to prove "I can DO that!";
2. A lack of a professional PC-house within 50 miles, that will do PTH

for

you, essentially "while you wait";
3. A need to make PTH boards for a top-secret national-defence project that
must be completed TONIGHT;

Yes, it simply not worth doing PTH for a hobby. That's why I am selling the
boards I make.
Admittedly up until now they have all been single sided requests.

--- In Homebrew_PCBs@y..., Adam Seychell <adam_seychell@y...> wrote:

The cost is not the problem since the carbon dispersion should be

available

free from one of the large colorant producers. The dye is similarly
available. I got 20 kg of dispersion paste for $130 AU. This is

enough to

make about 1000 liters of solution. I've used about 100 grams so

far. The

cost will be in building or setting up your chemical tanks. Plating

copper is

easy but trying to plate uniform smooth copper on to your PCB takes

a lot

more effort. I would say the carbon black process is simple

relative to

copper plating. In other words, if you can get successful copper

plating then

I'm sure the carbon black process will be easy for you. The success

rate for

plating holes is just about perfect, but it has taken me a long

time to get

at this stage. The guide I described is a good start. The only

concern I have

is that a different carbon black dispersion concentrate may give

different

results.


Adam

I had a nice long reply to the group, (covering two posts). But it
seems yahoo decided to screw up my message. But the gist was
the cost of producing prototypes at home or sending away. I am not
too concern at plating since I am thinking of buying a prototype
plating machine. I more worried about making the holes conductive.
Your prodeduce looks appealing.

Lates.

--- In Homebrew_PCBs@y..., "caveteursus" <j.walton@a...> wrote:

If I had a design with hundreds of boards, or multilayer boards, or
even tens of through-holes on 4 or 5 boards, I think that I could
find better uses of my time than etching them "homebrew" style.
Homebrew is great for PROTO's and One-off's, where you would like
something in a couple of hours, but the personal economics quickly
get swamped.

I have to admit I tradionally prototype using wirewrap method. I find
this faster with debugging. But since everyone is moving to highspeed
devices with more compact densities, (like PGA), I have no choice but
figure a way to easily make multilayer, (or doubly sided) boards at
home. The cost of sending away for boards to be made is a little
costly for me.

You are right about the economics part.

I was considering saving all my pennies and buying a commerical
prototype PCB plating machine. They are around the $1000.00 mark,
(the cost of sending out 20 boards to be made). I can always make my
money back by making prototypes for others at half the cost but this
isn't the main reason. But the main problem is making the holes
conductive in the first place which Adam address. This method seems
the easiest but major draw back is the experimenting with chemicals
to get the right ratio.

This is my first plan. My second plan would be to register in a local
community college PCB manufacturing course and use thier equipment.
$200.00 for the course and 50 prototypes made. ;) Cheaper I think.

I'm afraid it doesn't work like that. Buying a secondhand plating machine
ain't going to make you PCBs. There is long list of processing tanks
required along with an good understanding of the process. If ALL you are
trying to do is save money then your idea of making PTH at home is not
logical. Bath compositions are given to you by the vendors of the plating
additives and chemicals. You can also find much information in books. There
is no need for you to re-invent the wheel.

I've been interested the subject of plated through holes for a long
time, however the cost of making 2 sided PCB's is so low it is not worth
the effort to start the mess with chemicals and plating tanks, not least
getting rid of old chemicals can become a problem.

Example: Two boards of Two Sided board with through plated holes, LPI
mask and silk screen, any size upto 64 square inches. $33.00 (thirty
three US dollars) per board total cost $66.00 no tooling charges, there
are a few limitation on drill sizes the smallest is 20 mil. Plus
freight... Five days turnaround.
Hans Wedemeyer

j_hallows wrote:

I had a nice long reply to the group, (covering two posts). But it
seems yahoo decided to screw up my message. But the gist was
the cost of producing prototypes at home or sending away. I am not
too concern at plating since I am thinking of buying a prototype
plating machine. I more worried about making the holes conductive.
Your prodeduce looks appealing.

Lates.





Yahoo! Groups Sponsor

ADVERTISEMENT

To unsubscribe from this group, send an email to:
Homebrew_PCBs-unsubscribe@...



Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.

Hello,

This email message is a notification to let you know that
a file has been uploaded to the Files area of the Homebrew_PCBs
group.

File : /Homemade PCB equipment/Dscn0329.jpg
Uploaded by : alienrelics <alienrelics@...>
Description : Home-Brew PET-ctrl. PCB-drill by Janwrl

You can access this file at the URL



To learn more about file sharing for your group, please visit



Regards,

alienrelics <alienrelics@...>

At 04:11 AM 6/03/2002 -0000, you wrote:

--- In Homebrew_PCBs@y..., Adam Seychell <adam_seychell@y...> wrote:

The cost is not the problem since the carbon dispersion should be

available

free from one of the large colorant producers. The dye is similarly
available. I got 20 kg of dispersion paste for $130 AU. This is

enough to

make about 1000 liters of solution. I've used about 100 grams so

far. The

cost will be in building or setting up your chemical tanks. Plating

copper is

easy but trying to plate uniform smooth copper on to your PCB takes

a lot

more effort. I would say the carbon black process is simple

relative to

copper plating. In other words, if you can get successful copper

plating then

I'm sure the carbon black process will be easy for you. The success

rate for

plating holes is just about perfect, but it has taken me a long

time to get

at this stage. The guide I described is a good start. The only

concern I have

is that a different carbon black dispersion concentrate may give

different

results.


Adam

I had a nice long reply to the group, (covering two posts). But it
seems yahoo decided to screw up my message. But the gist was
the cost of producing prototypes at home or sending away. I am not
too concern at plating since I am thinking of buying a prototype
plating machine. I more worried about making the holes conductive.
Your prodeduce looks appealing.

Lates.

First you should worry about how your going to etch. If you decide on
pattern plate then you have choice of tin or tin/lead metal resist. If you
choose tin then you must use alkaline ammonia etch. If you choose tin/lead
then can use sulfuric/peroxide, ammonium persulfate etch, or ammonia etch.
However, I would be wary on having toxic lead plating solutions laying
around. For the ammonia etch it can be chloride or sulfate based. If
chloride based then you have major waste problems because the copper cannot
be recovered easily (at least what I know) and you will need to treat then
dump your solution ($$$). If you use sulfate based alkaline ammonia then
the etchant can be electrolytically regenerated although the etching rate
is much slower than chloride.

PCB fabrication may look simple on a flow chart but when it comes to
actually making it work its a whole different story.

Adam

--- In Homebrew_PCBs@y..., Adam Seychell <adam_seychell@y...> wrote:

I'm afraid it doesn't work like that. Buying a secondhand plating

machine

ain't going to make you PCBs.

I didn't mean second hand. I have been looking at the Prototype
plating machines. Like QuickPLATE. But they all seem to use the
process of squeezing conductive ink into the hole manually. The INK
in itself is expensive.

BTW: In your process the board is completely coated then plated
correct? So the board must have a thinner layer of copper to work
with in the first place or the thickness would be uneven correct?

Lates.

--
John Hallows

First you should worry about how your going to etch.

You read my mine this was my next question.

If you decide on
pattern plate then you have choice of tin or tin/lead metal resist.

If you

choose tin then you must use alkaline ammonia etch. If you choose

tin/lead

then can use sulfuric/peroxide, ammonium persulfate etch, or

ammonia etch.

Is this the same stuff called Liquid Tin by MG Chemicals and a
similar prodouct by Datak? Or would these get disolved by the etching
solution?

However, I would be wary on having toxic lead plating solutions

laying

around. For the ammonia etch it can be chloride or sulfate based. If
chloride based then you have major waste problems because the

copper cannot

be recovered easily (at least what I know) and you will need to

treat then

dump your solution ($$$).

This is like ferric chloride?

If you use sulfate based alkaline ammonia then

the etchant can be electrolytically regenerated although the

etching rate

is much slower than chloride.

PCB fabrication may look simple on a flow chart but when it comes to
actually making it work its a whole different story.

Please excuse my ignorance. I have a lot zeal and a lot to learn.

At 06:32 AM 7/03/2002 -0000, you wrote:

--- In Homebrew_PCBs@y..., Adam Seychell <adam_seychell@y...> wrote:

I'm afraid it doesn't work like that. Buying a secondhand plating

machine

ain't going to make you PCBs.

I didn't mean second hand. I have been looking at the Prototype
plating machines. Like QuickPLATE. But they all seem to use the
process of squeezing conductive ink into the hole manually. The INK
in itself is expensive.

BTW: In your process the board is completely coated then plated
correct? So the board must have a thinner layer of copper to work
with in the first place or the thickness would be uneven correct?

Lates.

--
John Hallows

By starting off with blank copper cladded board you mean ? then yes.
The process is called "pattern plate" which I think is the most common
method of making through hole boards, both double sided and multilayer. The
other widely used method is "panel plate". This requires better setup with
photoresist and it must "tent" the hole walls to stop etchant from removing
copper inside the holes.
The carbon black though hole method is not suitable for making large
surfaces conductive. The holes are of relatively short dimension so the
contacts made to the carbon (i.e. at the hole ends where it meets up with
copper foil) can propagate copper through the hole wall during the first 1
to 2 minutes of the copper electroplating process.


Here is a good link describing the steps on manufacturing a multilayer
board (pattern plating).




some more PCB info can be had at;

Ok, copper etchants come in many different flavors. The ammonia alkaline are
type the most commonly used for tin or tin/lead metal resists (i.e. pattern
plating). The tin forms near perfect resistance (3 um thickness) to the
ammonia type etchants, especially the sulfate based. I recommend visiting
your local university library and getting hold of a book called "Coombs'
Printed Circuits Handbook". It has many of the basics of PCB fabrication that
can start you off.

Here is the alkaline ammonia sulfate etchant I use. It is suitable for room
temp operation; Note: the high alkalinity makes it not suitable for use with
photoresists.

CuSO4.5H20 - 150 to 190 g/l (optimum 175 g/l)
25%(wt) aqua ammonia - 70% (vol.)
98% sulfuric acid - 3.0% to 4.0% (vol.)

pH should be between 10 and 11, adjust with aqua ammonia additions.
Tank must be sealed virtually air tight when not in use. Otherwise NH3 will
evaporate over time and pH drops significantly. regeneration is done with
stainless steel anodes in stagnate solution at current density between 3 and
5 A/dm2. Etch times at 25???C using air bubble agitation is 20 to 25 minutes
for 35 um copper foil. Only one place in the world I know of markets this
type of etchant, and that is the German company Elo-Chem. You won't see it
documented in many places.



No one uses electroless tin unless they have to. The tin is plated on all the
tracks directly after copper plating. Electrolytic tin plating works much
faster, cheaper, safer, more reliable, lower maintenance and more predictable
than electroless tin. The bath I use is the acid stannous sulfate type (looks
like banana flavored milk drink). See your friendly plating supplier for
necessary brighteners and chemicals.




j_hallows wrote:

Yep, already had those in the Bookmarks section. I might have
gotten them from Adam originally.

Steve Greenfield

--- Adam Seychell <adam_seychell@...> wrote:

Here is a good link describing the steps on manufacturing a
multilayer
board (pattern plating).



some more PCB info can be had at;

__________________________________________________
Do You Yahoo!?
Try FREE Yahoo! Mail - the world's greatest free email!

Hi , i am Eduardo , and i make a pcb plotter , see it at :

Em branco
Quem quiser o programa para controle da Plotter pode baixar em :

Home Build Plotter Driver Download :

This from Yahoo:

Dear Yahoo! Groups Members,

The Yahoo! Groups service will be down Friday March 15 9:00 PM PST
(GMT-8) as we move our servers to a new facility. We expect the
service to be back up the morning of Sunday March 17.

During this time the web site will be unavailable and email will
not be delivered. (Some users may experience email non-delivery
notices, but all email should be delivered once service has
resumed.) Please note: once the service is back up, there will be
email delays due to backlog. We expect these delays to last no
longer than 1 day. Please do not re-send email to your group as it
will only add to delays.

We apologize for any inconvenience this may cause.

The Yahoo! Groups Team


It means just what it says, so please be advised!

Steve Greenfield


__________________________________________________
Do You Yahoo!?
Yahoo! Sports - live college hoops coverage

Em branco
I forgot this dll , win95io.dll to run printer port , only 1kb.

Hello,

This email message is a notification to let you know that
a file has been uploaded to the Files area of the Homebrew_PCBs
group.

File : /How_to_solder_1.pdf
Uploaded by : alienrelics <alienrelics@...>
Description : How To Solder- one page PDF file

You can access this file at the URL



To learn more about file sharing for your group, please visit



Regards,

alienrelics <alienrelics@...>

Found a cool link- how to build a $20 hot air pen for soldering
surface mount!


7679854/

Here's the Rat Shack $10 desoldering pen he mentions:

5Fname=CTLG%5F005%5F006%5F003%5F000&product%5Fid=64%2D2060

I'm off to Rat Shack!

Steve Greenfield

Here is a link to building a Hot Air Pencil

Hans W