Homebrew PCBs

I'm a hobbyist who builds occasional circuit boards.  So unlike
some contributors I use circuit boards as tools.  (Some readers have
turned circuit board technology into a very interesting hobby in its
own right.)

My approach is minimalist. I want to use the least amount of hardware
to build my boards.  I just moved from a laundry iron to laminator for
toner transfer because I'm now working with SMT components. With
through hole components and .040 traces the iron did me well.

  
I have had good luck with Pulsar's products.  The cost
doesn't bother
me because $15 of toner transfer sheeting will last me a year.

I think many occasional board builders are like me, and prefer to keep
it simple.

I want to talk about the Pulsar Green Film.  I really like this stuff
because I can etch boards with a pair of gloves and a foam brush.  My
last board was 4 inches square with 1-ounce copper.  It took about
four minutes, using 2 ounces of ferric chloride to etch the board.  No
heaters, no tanks, no agitation needed. 

With this process it pays to leave large areas of copper on the board.
 The brush system rapidly removes narrow copper traces.  The wider
areas take longer.  

Whether you use paper or some other product for your toner transfer
medium, take a look at the Green Film.  For the occasional user it can
eliminate the need for more complex etching equipment.

Hi Bob,

I agree with you. Some people on this list have made
homebrewing pcbs into a high art form, When many of us
are just hobbyists wanting to do a few boards now and
then. These "artists' look down their noses at some of
the simple methods and discourage discussion by the
newbies. (Hi Stefan) (Listowner take note)

I haven't used the Pulsar "Green Film" , but I got the
same results with some leftover gold metallic "laser
foil" and some Reynold's Parchment Paper. It's a
metallized layer on a polyester film that is grabbed
by the toner when heated. It is used for hot stamping
foil seals on material and in the early days before
inkjets, one of the few ways to add color to your
documents.

It worked well on the pcb., I think part of the
success is that it flattens out the toner and seals up
some of the pinholes.

I like your foam brush idea, I used part of a sponge.

Keep posting the simple solutions.

Myc


--- bob_ledoux <bobledoux@...> wrote:

> I'm a hobbyist who builds occasional circuit boards.
>  So unlike
> some contributors I use circuit boards as tools. 
> (Some readers have
> turned circuit board technology into a very
> interesting hobby in its
> own right.)
> 
> My approach is minimalist. I want to use the least
> amount of hardware
> to build my boards.  I just moved from a laundry
> iron to laminator for
> toner transfer because I'm now working with SMT
> components. With
> through hole components and .040 traces the iron did
> me well.
> 
>   
> I have had good luck with Pulsar's products.  The
> cost
> doesn't bother
> me because $15 of toner transfer sheeting will last
> me a year.
> 
> I think many occasional board builders are like me,
> and prefer to keep
> it simple.
> 
> I want to talk about the Pulsar Green Film.  I
> really like this stuff
> because I can etch boards with a pair of gloves and
> a foam brush.  My
> last board was 4 inches square with 1-ounce copper. 
> It took about
> four minutes, using 2 ounces of ferric chloride to
> etch the board.  No
> heaters, no tanks, no agitation needed. 
> 
> With this process it pays to leave large areas of
> copper on the board.
>  The brush system rapidly removes narrow copper
> traces.  The wider
> areas take longer.  
> 
> Whether you use paper or some other product for your
> toner transfer
> medium, take a look at the Green Film.  For the
> occasional user it can
> eliminate the need for more complex etching
> equipment.
> 
> 
> 



		
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On Sun, 03 Jul 2005 12:51:11 +0200, Mycroft2152 <mycroft2152@...>  
wrote:

>  These "artists' look down their noses at some of
> the simple methods and discourage discussion by the
> newbies. (Hi Stefan) (Listowner take note)


No, it is simply more experienced people who have been there pointing out  
the disadvatages.
You can make a PCB with some blank board, and a sharp knife. That's about  
as basic as it gets.
However, a minium effort must be put in to get basic quality (or in other  
words a board that is at least similar to the layout you had in mind and  
has no errors like shorts and gaps).

Nobody here discourages the most basic discussion about PCB making (and  
you have the archives to come up with an example.). If i see a flaw with a  
method i will say so, that's what a list is for after all to get help from  
people who have tried it. A wholly aggrable listmember that only ever says  
"great idea, do it" isn't very useful at all.

The listowner sees that similar, as you see he only steps in if a  
discussion gets too much off topic, and does never diccourage any PCB  
discussion now matter how basic the method.

I really don't know what your problem with my posts is. I ask you to  
please come up with an example, and then we will work on doing something  
about it. But if you can't do that please stop saying things about me that  
aren't correct.


ST

Stefan,

There's a big difference between mentoring newbies and
monopolizing discussions as the self proclaimed
expert. My problem with your posts is your negative
tone about anything that's either not your idea or not
your idea of the moment.

By moopolizing the posts. i suggest you figure the
percentage of the posts on this list that are from you
alone. My joking reference to the chicken grill motor
was my way of suggesting you give others a chance to
say something.

I've seen too many good threads die a slow death after
your "expert" comments discouraging them.

I for one, try to skip your posts, on this list an the
many other lists you are on.

There's an old saying that you learn best from making
your own mistakes. Learn from this one.

Myc

--- Stefan Trethan <stefan_trethan@...> wrote:

> On Sun, 03 Jul 2005 12:51:11 +0200, Mycroft2152
> <mycroft2152@...>  
> wrote:
> 
> >  These "artists' look down their noses at some of
> > the simple methods and discourage discussion by
> the
> > newbies. (Hi Stefan) (Listowner take note)
> 
> 
> No, it is simply more experienced people who have
> been there pointing out  
> the disadvatages.
> You can make a PCB with some blank board, and a
> sharp knife. That's about  
> as basic as it gets.
> However, a minium effort must be put in to get basic
> quality (or in other  
> words a board that is at least similar to the layout
> you had in mind and  
> has no errors like shorts and gaps).
> 
> Nobody here discourages the most basic discussion
> about PCB making (and  
> you have the archives to come up with an example.).
> If i see a flaw with a  
> method i will say so, that's what a list is for
> after all to get help from  
> people who have tried it. A wholly aggrable
> listmember that only ever says  
> "great idea, do it" isn't very useful at all.
> 
> The listowner sees that similar, as you see he only
> steps in if a  
> discussion gets too much off topic, and does never
> diccourage any PCB  
> discussion now matter how basic the method.
> 
> I really don't know what your problem with my posts
> is. I ask you to  
> please come up with an example, and then we will
> work on doing something  
> about it. But if you can't do that please stop
> saying things about me that  
> aren't correct.
> 
> 
> ST
> 
> 
> 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
> 
> 
>     Homebrew_PCBs-unsubscribe@yahoogroups.com
> 
>  
> 
> 
> 



		
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Stefan,

I've read through all 9000+ postings on this board.  I very much
appreciate the contributions you, and others, have made to the hobby
technology.  My comments are not intended as a criticism.

Some readers must have some elegant circuit board facilities befitting
a small production facility.  That is fine. 

But I still had to do hours of reading and testing to get a simple PCB
process for my occasional use.  The key for me was to avoid new
hardware on my electronics bench.  I've made space for a laminator, as
a concession to smd parts, but I didn't want to spend time and make
space creating an etching system with tanks and other objects de art.

My workbench is in the house.  I don't want ferric chloride tanks in
the home.  Its nice taking the dirty job outside. 

So the Green Film, at $8 for 15 feet, has allowed me a hardware-free
etching approach. No mess, no fuss.

The other outside job is drilling pcb holes.  As much as I like
carbide drill bits, they are fragile and require precise spindle
mechanisms operating at high speeds.  My solution is low tech.  I use
a $39 Harbor Freight drill press driving 1/32 (.032) steel drill bits
that I buy by the dozen from Enco or MSC for 21 cents each. 

They don't last long, but I can by thousands for the cost of creating
a precise drilling system. If you want to build something precise
consider this.  He has two versions.

http://www.jerry-howell.com/MiniDrillPress.html
 






--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
<stefan_trethan@g...> wrote:
> On Sun, 03 Jul 2005 12:51:11 +0200, Mycroft2152 <mycroft2152@y...>  
> wrote:
> 
> >  These "artists' look down their noses at some of
> > the simple methods and discourage discussion by the
> > newbies. (Hi Stefan) (Listowner take note)
> 
> 
> No, it is simply more experienced people who have been there
pointing out  
> the disadvatages.
> You can make a PCB with some blank board, and a sharp knife. That's
about  
> as basic as it gets.
> However, a minium effort must be put in to get basic quality (or in
other  
> words a board that is at least similar to the layout you had in mind
and  
> has no errors like shorts and gaps).
> 
> Nobody here discourages the most basic discussion about PCB making
(and  
> you have the archives to come up with an example.). If i see a flaw
with a  
> method i will say so, that's what a list is for after all to get
help from  
> people who have tried it. A wholly aggrable listmember that only
ever says  
> "great idea, do it" isn't very useful at all.
> 
> The listowner sees that similar, as you see he only steps in if a  
> discussion gets too much off topic, and does never diccourage any
PCB  
> discussion now matter how basic the method.
> 
> I really don't know what your problem with my posts is. I ask you
to  
> please come up with an example, and then we will work on doing
something  
> about it. But if you can't do that please stop saying things about
me that  

> aren't correct.
> 
> 
> ST

I really don't know what part of "discussion" and "opinion" you don't  
understand.
All posts are understood as opinion, like it, use it, don't like it,  
ignore it or argue aganst it.

If i don't like some idea i usually have good reasons for that, and also  
point them out.
I'd say it is very valuable to know what problems to expect, which you  
mightn't even have thought of before.

As much joking as your reference to the chicken grill motor might have  
been, it was totally useless as you don't offer the sightest reason why it  
isn't a good thing, other than you don't like it. That is what i call a  
negative tone about something.

I will not reply to your posts any more, and if anyone else is  
specifically not wanting my criticism just say so.

All i can really learn from this is that some people just don't appreciate  
free advice and prefer "go on, try it, sounds great!" over "been there  
done that, and that's why it didn't work:".

I reply to many posts - so what? I have tried a few things for PCB making.  
I'd like more people to reply more often, then i wouldn't have to waste so  
much time with trying things others have already found non-working.
Learning from your own mistakes is nice and all, but if i can avoid them  
that's nice too, and less work.

ST

On Sun, 03 Jul 2005 15:37:06 +0200, Mycroft2152 <mycroft2152@...>  
wrote:

> Stefan,
> There's a big difference between mentoring newbies and
> monopolizing discussions as the self proclaimed
> expert. My problem with your posts is your negative
> tone about anything that's either not your idea or not
> your idea of the moment.
> By moopolizing the posts. i suggest you figure the
> percentage of the posts on this list that are from you
> alone. My joking reference to the chicken grill motor
> was my way of suggesting you give others a chance to
> say something.
> I've seen too many good threads die a slow death after
> your "expert" comments discouraging them.
> I for one, try to skip your posts, on this list an the
> many other lists you are on.
> There's an old saying that you learn best from making
> your own mistakes. Learn from this one.
> Myc

Stefan,

I'm releived you have decided not to reply to my
posts. It will be that fewer of your posts I have to
ignore.

I'll leave yu with two thoughts:

Don't try the "Been there done that" line with your
kids, It didn't work for yur parent and wo't work for
you. Experience is the best teacher.

Finally, Remember anything free is worth as much as 
you paid for it! 

Have a good life,

Myc


--- Stefan Trethan <stefan_trethan@...> wrote:

> I really don't know what part of "discussion" and
> "opinion" you don't  
> understand.
> All posts are understood as opinion, like it, use
> it, don't like it,  
> ignore it or argue aganst it.
> 
> If i don't like some idea i usually have good
> reasons for that, and also  
> point them out.
> I'd say it is very valuable to know what problems to
> expect, which you  
> mightn't even have thought of before.
> 
> As much joking as your reference to the chicken
> grill motor might have  
> been, it was totally useless as you don't offer the
> sightest reason why it  
> isn't a good thing, other than you don't like it.
> That is what i call a  
> negative tone about something.
> 
> I will not reply to your posts any more, and if
> anyone else is  
> specifically not wanting my criticism just say so.
> 
> All i can really learn from this is that some people
> just don't appreciate  
> free advice and prefer "go on, try it, sounds
> great!" over "been there  
> done that, and that's why it didn't work:".
> 
> I reply to many posts - so what? I have tried a few
> things for PCB making.  
> I'd like more people to reply more often, then i
> wouldn't have to waste so  
> much time with trying things others have already
> found non-working.
> Learning from your own mistakes is nice and all, but
> if i can avoid them  
> that's nice too, and less work.
> 
> ST
> 
> On Sun, 03 Jul 2005 15:37:06 +0200, Mycroft2152
> <mycroft2152@...>  
> wrote:
> 
> > Stefan,
> > There's a big difference between mentoring newbies
> and
> > monopolizing discussions as the self proclaimed
> > expert. My problem with your posts is your
> negative
> > tone about anything that's either not your idea or
> not
> > your idea of the moment.
> > By moopolizing the posts. i suggest you figure the
> > percentage of the posts on this list that are from
> you
> > alone. My joking reference to the chicken grill
> motor
> > was my way of suggesting you give others a chance
> to
> > say something.
> > I've seen too many good threads die a slow death
> after
> > your "expert" comments discouraging them.
> > I for one, try to skip your posts, on this list an
> the
> > many other lists you are on.
> > There's an old saying that you learn best from
> making
> > your own mistakes. Learn from this one.
> > Myc
> 
> 
> 
> 
> 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
> 
> 
>     Homebrew_PCBs-unsubscribe@yahoogroups.com
> 
>  
> 
> 
> 


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On Sun, 03 Jul 2005 15:41:50 +0200, bob_ledoux <bobledoux@...>  
wrote:

> Stefan,
> I've read through all 9000+ postings on this board.  I very much
> appreciate the contributions you, and others, have made to the hobby
> technology.  My comments are not intended as a criticism.

I know there are many posts, and i really don't think the archives are  
practical to start for a beginner.
Better read the tutorials in the links section, there you get a condensed  
howto from one person, but several versions from different persons. Then  
discuss your options on the list.

Some have suggested a kind of knoweledge base /wiki for the list, i don't  
think it would work 'cause there are so many different opinions. I think  
the best is if everyone that wants writes a few personal pages about his  
findings in PCB making and puts a link in the links section. I may do so  
one day.

> Some readers must have some elegant circuit board facilities befitting
> a small production facility.  That is fine.
> But I still had to do hours of reading and testing to get a simple PCB
> process for my occasional use.  The key for me was to avoid new
> hardware on my electronics bench.  I've made space for a laminator, as
> a concession to smd parts, but I didn't want to spend time and make
> space creating an etching system with tanks and other objects de art.
> My workbench is in the house.  I don't want ferric chloride tanks in
> the home.  Its nice taking the dirty job outside.
> So the Green Film, at $8 for 15 feet, has allowed me a hardware-free
> etching approach. No mess, no fuss.
> The other outside job is drilling pcb holes.  As much as I like
> carbide drill bits, they are fragile and require precise spindle
> mechanisms operating at high speeds.  My solution is low tech.  I use
> a $39 Harbor Freight drill press driving 1/32 (.032) steel drill bits
> that I buy by the dozen from Enco or MSC for 21 cents each.
> They don't last long, but I can by thousands for the cost of creating
> a precise drilling system. If you want to build something precise
> consider this.  He has two versions.
> http://www.jerry-howell.com/MiniDrillPress.html


I did the very same thing you do now for several years, and i don't say it  
isn't a possibility.
But if someone comes and for example says he has bad tranfer results using  
a clothes iron, what should i do? Say nothing when i know perfectly well  
that a laminator/fuser will solve the problem, just because the iron means  
less hardware? If some option is not suitable for you 'cause of certain  
requirements, point that out and everyone will understand.

Also, i do understand beginners come here to learn the basics, and they  
are always provided with plenty of suggestions, but this is as much a  
place for advanced discussion as it is for beginners. If you suggest tray  
etching with a brush and green film - that's fine with me, i won't go and  
do it however, just as you won't go and build my CuCl tank any time soon.  
I really don't see a problem with that.

I can only suggest what i think is best, not what some people want to  
hear, sorry 'bout that.

Now enough of that nonsense and back to making PCBs.
For drilling, someone here suggested a pivoting drill press to me, i made  
one and it works really well.
Basically you mount your drill on a pivoting arm, about 30 to 50 cm long,  
and all mechanics that are needed are the bearings at the end (I used two  
thrust bearings). You should find the details in the archives. Very cheap  
and precise.
I used HSS drills for years too, but in FR4 they dull really quick and the  
holes are much better with carbide (cleaner cut and less burr).

ST

--- In Homebrew_PCBs@yahoogroups.com, Mycroft2152 <mycroft2152@y...> 
wrote:
...
>  These "artists' look down their noses at some of
> the simple methods and discourage discussion by the
> newbies. (Hi Stefan) (Listowner take note)

Actually, Mycroft, what I've noticed is that you are overly sensitive 
to anything Stefan posts. I take all complaints seriously and go back 
and read and re-read the posts leading to it, and I've not been able 
to figure out what exactly you are objecting to.

Steve Greenfield
Listowner

Ah, don't worry Steve,  it's nothing.  Mycroft and Stefan just can't see
eye-to-eye on whether a barbecue chicken brochette should turn up and away
from the chef, or down and towards.  I prefer a propane torch myself for
that bacon-crispy taste.  If my wife wants to use the brochette, I use a 12V
stepper with booster cables onto my car battery...

Robert
:D



-----Message d'origine-----
De : Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] De
la part de Steve
Envoyé : juillet 6 2005 23:41
À : Homebrew_PCBs@yahoogroups.com
Objet : [Homebrew_PCBs] Newbies vs Oldies


--- In Homebrew_PCBs@yahoogroups.com, Mycroft2152 <mycroft2152@y...> 
wrote:
...
>  These "artists' look down their noses at some of
> the simple methods and discourage discussion by the
> newbies. (Hi Stefan) (Listowner take note)

Actually, Mycroft, what I've noticed is that you are overly sensitive 
to anything Stefan posts. I take all complaints seriously and go back 
and read and re-read the posts leading to it, and I've not been able 
to figure out what exactly you are objecting to.

Steve Greenfield
Listowner




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

--- In Homebrew_PCBs@yahoogroups.com, Mycroft2152 <mycroft2152@y...> 
wrote:
> Stefan,
> 
> There's a big difference between mentoring newbies and
> monopolizing discussions as the self proclaimed
> expert. My problem with your posts is your negative
> tone about anything that's either not your idea or not
> your idea of the moment.

I don't like bullies on lists, and it appears to me -you- are 
bullying. Stefan -cannot- "monopolize" anything here. He can post 100 
replies to one message, that does not prevent anyone else from 
replying, too.

Steve Greenfield
Listowner

I guess I'm an Oldie.

I spent 12 years trying to teach companies such as IBM, HP, Sperry Univac, Burroughs, and countless board shops how to build PCBs.  There were technical successes (Sperry in Bristol, TN, and HP in Garden of the Gods, CO were memorable) and failures (IBM, Austin, TX), but in the end economics trumped technology - except in the cases of the Mafia shops that were laundering money - and essentially all PCB production has moved to SE Asia.  

So I have a bit of experience making circuit boards.  

For the most part I keep quiet unless the poster is really going to waste a lot of time on something that doesn't stand a chance of working.  So if someone wants to try electro, mechanical milling, or some other off-the-wall process, I can sometimes point out the pitfalls that they will encounter, but I would never suggest that it can't be done.  

When a newspaper reporter asked Thomas Edison  what progress he had made in developing his electric light after two years of work, he is said to have replied something like, "Well, I know about a thousand things that don't work."  Invention is 1% inspiration and 99% perspiration.  

So for you Newbies who what to try something different - go for it.  But listen to the consul of the Oldies - we've been there and generally have had more failures than successes.  We don't want to dampen you enthusiasm, but just want to make you aware of what has gone before.  There's no need to repeat historical failures.

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

Hi Robert,

Good points.

Yes, and I prefer the toilet paper to unroll from over the top. I'm 
sure Stefan,likes it to unroll from underneath. :)

Seriously, let's keep this in perspective, this is not a life and 
death issue. It's a simple difference of opinion on the style of the 
mentoring process.

Remember there is a real life outside these lists. (At least for 
some of us.)

Myc

--- In Homebrew_PCBs@yahoogroups.com, Robert Hedan 
<robert.hedan@v...> wrote:
> Ah, don't worry Steve,  it's nothing.  Mycroft and Stefan just 
can't see
> eye-to-eye on whether a barbecue chicken brochette should turn up 
and away
> from the chef, or down and towards.  I prefer a propane torch 
myself for
> that bacon-crispy taste.  If my wife wants to use the brochette, I 
use a 12V
> stepper with booster cables onto my car battery...
> 
> Robert
> :D
> 
> 
> 
> -----Message d'origine-----
> De : Homebrew_PCBs@yahoogroups.com 
[mailto:Homebrew_PCBs@yahoogroups.com] De
> la part de Steve
> Envoyé : juillet 6 2005 23:41
> À : Homebrew_PCBs@yahoogroups.com
> Objet : [Homebrew_PCBs] Newbies vs Oldies
> 
> 
> --- In Homebrew_PCBs@yahoogroups.com, Mycroft2152 
<mycroft2152@y...> 
> wrote:
> ...
> >  These "artists' look down their noses at some of
> > the simple methods and discourage discussion by the
> > newbies. (Hi Stefan) (Listowner take note)
> 
> Actually, Mycroft, what I've noticed is that you are overly 
sensitive 
> to anything Stefan posts. I take all complaints seriously and go 
back 
> and read and re-read the posts leading to it, and I've not been 
able 
> to figure out what exactly you are objecting to.
> 
> Steve Greenfield
> Listowner
> 
> 
> 
> 
> 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

Hi Steve,

I was disappointed to see you revert to name calling. Open 
disagreements are healthy.

I suggest you reread the Stefan's posts and note the number of threads 
that died after he responded.

I am not 'overly sensitive" to his comments, I was just tired of 
wading through the sheer number of his repetitive andf negative posts 
that dominate the list. There is a big difference between mentoring 
and the old adage "In the land of the blind, a one-eyed man is king"

As the listowner, you have the abilitiy and resposibility to set the 
tone of the list. It's obvious that you are more interested in the 
activiy of your list as indicated by the volume of posts rather than 
the quality. Check your stats on active members who are actually 
posting.

You have mentioned that you "own" 30 lists. Please explain to me why 
this is so important. I cannot understand the importance of being a 
listowner. Is it like collecting baseball cards?

As a list member, I have the priviledge to read and reply to the posts 
as I see fit. This is Stefan's privilege also. You, on the other hand, 
have the option to take this privilege away.

Myc







--- In Homebrew_PCBs@yahoogroups.com, "Steve" <alienrelics@y...> wrote:
> --- In Homebrew_PCBs@yahoogroups.com, Mycroft2152 <mycroft2152@y...> 
> wrote:
> > Stefan,
> > 
> > There's a big difference between mentoring newbies and
> > monopolizing discussions as the self proclaimed
> > expert. My problem with your posts is your negative
> > tone about anything that's either not your idea or not
> > your idea of the moment.
> 
> I don't like bullies on lists, and it appears to me -you- are 
> bullying. Stefan -cannot- "monopolize" anything here. He can post 
100 

> replies to one message, that does not prevent anyone else from 
> replying, too.
> 
> Steve Greenfield
> Listowner

> So for you Newbies who what to try something different - go for 
it.  But listen to the consul of the Oldies - we've been there and 
generally have had more failures than successes.  We don't want to 
dampen you enthusiasm, but just want to make you aware of what has 
gone before.  There's no need to repeat historical failures.
> 
> 

Hi Earl,

This is the true spirit of what forums should be like.  I am a 
newbie and I listen carefully what the "Oldies" have to say - Stefan 
being an "oldie".  Experience is worth a LOT!  Often times I come up 
with an idea, voice it in a forum, and it gets shot down as being 
tried already.  That isn't a bad thing, it saves me a lot of time by 
avoiding all the pitfalls of other's experiements.

However, if a person is an adventerous newbie, listen to the details 
of what has been tried, and see if you can put a new spin on some of 
them.  

Personally, I find the advice in this forum and E-101 to be very 
good from the "Elders".  Much appreaciate from this Newbie!

Chris'

On Thursday 07 July 2005 12:17 am, Earl T. Hackett, Jr. wrote:

> I spent 12 years trying to teach companies such as IBM, HP, Sperry Univac,
> Burroughs, and countless board shops how to build PCBs.  There were
> technical successes (Sperry in Bristol, TN, and HP in Garden of the Gods,
> CO were memorable) and failures (IBM, Austin, TX), but in the end economics
> trumped technology - except in the cases of the Mafia shops that were
> laundering money - and essentially all PCB production has moved to SE Asia.
>
> So I have a bit of experience making circuit boards.

Given that,  can you give me some idea as to why it is that some boards seem 
to be so easy to work on (in terms of repairs etc.) where you can unsolder 
parts,  install new ones and solder them just fine,  while at the same time 
with some of the same kind of parts it seems that no matter how careful you 
are you end up yanking the plating out of the hole,  perhaps lifting the 
trace on one side,  etc. -- using the same tools and methods?

I can *see* some differences between boards.  I can *feel* some differences in 
terms of being able to unsolder or to remove the component or whatever,  and 
differences in the weight of the copper,  etc.  But I don't have the 
experience in making boards to be able to quantify this stuff.

And why the heck are so many boards made where the bend the component leads 
over so tight against the board,  making it so difficult to deal with later?

>     Hi Robert,
>
>  Good points.
>
>  Yes, and I prefer the toilet paper to unroll from over the top. I'm
>  sure Stefan,likes it to unroll from underneath. :)
>


Stefan doesn't care which way the paper hangs, so long as the dispenser is
driven by a chicken grill motor.

Tony

--- In Homebrew_PCBs@yahoogroups.com, "Tony Smith" <ajsmith@r...> wrote:
> >     Hi Robert,
> >
> >  Good points.
> >
> >  Yes, and I prefer the toilet paper to unroll from over the top. I'm
> >  sure Stefan,likes it to unroll from underneath. :)
> >
> 
> 
> Stefan doesn't care which way the paper hangs, so long as the
dispenser is
> driven by a chicken grill motor.
> 
> Tony

well, at least he uses TP.

I do think there are a lot of interchanges where the distinction
between fact and opinion are blurred.  This isn't only group that has
that problem, though.

People need to a) be considerate of others and not dismiss their ideas
so readily and b) not be so thin skinned when their pet idea gets shot
down.

By the way, I'm seeing a really long lag between posting something and
seeing it show up in the group.   Its kind of bad when I post
something and then see 5 responses that say the same thing show up
before mine does.  That makes me want to not contribute more than
anything else...

Phil

The ability of a board to withstand the stress of repair depends upon the back side treatment of the original copper foil.  FirCopper foil can be made by electroplating it on large stainless steel drums or rolling.  The best technique for developing  adhesion to an epoxy board was a nodulated copper that was overcoated with a brass alloy as produced by Gould Electronics.  My understanding is that the bulk of the foil was plated with a fine grain structure on a large drum, peeled off, and passed into a second copper bath with different plating conditions which produced copper nodules.  A third bath plated a very  thin brass layer on top of the nodules.  Cross sections and some electron microscope work seemed to support this, but no one has to my knowledge ever released the details of their process.  The copper nodules provided a mechanical interlocking as well as increased surface area for a chemical bond.  Go to 

http://www.gould.com/pr.htm

where you will see a nice electron micrograph of the bottom side of their foil.  

This is obviously an expensive process so other foil manufacturers in an attempt to get some of the business began looking for less expensive methods.  Some just plated the brass alloy, others just put on a black oxide, none of which provided the peel strength of the nodulated copper.  From just looking at the finished board it is very difficult to tell one foil from the other.  If you look at the bare epoxy and know what to look for you can see the print of the copper nodules on a board made with Gould foil.  Boards made with other foils have a much smoother epoxy surface. 

As for the overly crimped leads, this is probably a fix for a portion of the assembly process that was giving them trouble.  Components can be nocked out of position by a number of things, insertion of other components, handling, and the solder wave itself.  If you have the clearance around the pads as on low density and some medium density boards, the easiest way to keep things where you want them is to really bend the leads over.  A production shop really hates rework.

----- Original Message ----- 
  From: Roy J. Tellason 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Thursday, July 07, 2005 5:08 PM
  Subject: Re: [Homebrew_PCBs] Newbies vs Oldies


  ...can you give me some idea as to why it is that some boards seem 
  to be so easy to work on (in terms of repairs etc.) where you can unsolder 
  parts,  install new ones and solder them just fine,  while at the same time 
  with some of the same kind of parts it seems that no matter how careful you 
  are you end up yanking the plating out of the hole,  perhaps lifting the 
  trace on one side,  etc. -- using the same tools and methods?

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

On Fri, 08 Jul 2005 01:24:01 +0200, Tony Smith <ajsmith@...>  
wrote:

>
> Stefan doesn't care which way the paper hangs, so long as the dispenser  
> is
> driven by a chicken grill motor.
> Tony


Would be way too slow for unrolling paper. I don't have that much time to  
waste on the loo.

ST

> On Fri, 08 Jul 2005 01:24:01 +0200, Tony Smith <ajsmith@...>
> wrote:
>
>>
>> Stefan doesn't care which way the paper hangs, so long as the dispenser
>> is
>> driven by a chicken grill motor.
>> Tony
>
>
> Would be way too slow for unrolling paper. I don't have that much time to
> waste on the loo.
>


Oh come on.  Add a few gears (left over from the old HP Laserjets, we know
you don't have any laminators :) ) to get the speed up.

Only problem is constant velocity, the paper will dispense faster as the
roll unwinds.  Oops, hang on, other way round.

You'll need some way to measure paper usage (bounce IR off the paper? 
ultrasonic?) so you can adjust the speed.  You need a PCB to mount the
electronics, but I figure you can sort that out.  Sounds like a job for a
PIC (or a PicAxe).

Web enable it so you can check the paper status before making the trip, or
to send you email before it runs out.  Automatically order from
www.ToiletPaperOnline.com?  Startup!  IPO!!  Oh, it's 2005, not 1997.

You can estimate the number of squares left, but that gets tricky as some
paper is thicker than others.  You need the paper to pass thru another
sensor to measure its thickness.  Knowing the thickness of the paper and
the size of the remaining roll you can calculate the number of squares
left.  Even that gets hard as the size of the squares varies, apparently
Europe has metric toilet paper.  (It's true, I tell ya, I read it on the
'net).

Hey, that actually solves the constant velocity problem.  The paper is
pulled out by rollers rather than just spinning the roll.  Make the
rollers big enough and you won't need to gear up the chicken motor.  Don't
need the PIC either, except to web enable it.

Another catch is the size of the cardboard inner tube varies, so you'll
need to measure that as well.

Add a IR pair to detect your hand waving in front of it (like hand dryers)
to dispense the paper and you're set (hmmm a gas sensor could ... ok never
mind!).

Tony

--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
<stefan_trethan@g...> wrote:
> On Sun, 03 Jul 2005 12:51:11 +0200, Mycroft2152 <mycroft2152@y...>  
> wrote:
> 
> >  These "artists' look down their noses at some of
> > the simple methods and discourage discussion by the
> > newbies. (Hi Stefan) (Listowner take note)
> 
> 
> No, it is simply more experienced people who have been there
pointing out  
> the disadvatages.
> You can make a PCB with some blank board, and a sharp knife. That's
about  
> as basic as it gets.


just reading some old posts to see what the 'best' (cheap) paper is
these days.

I gotta laugh at this thread though.

And Stefan, can't you see why you are so much a 'purist'?  

...Sharp knife....  why does it need to be sharp ?  (just kidding)

Dave

> Given that,  can you give me some idea as to why it is that some
boards seem 
> to be so easy to work on (in terms of repairs etc.) where you can
unsolder 
> parts,  install new ones and solder them just fine,  while at the
same time 
> with some of the same kind of parts it seems that no matter how
careful you 
> are you end up yanking the plating out of the hole,  perhaps lifting
the 
> trace on one side,  etc. -- using the same tools and methods?
> 
> I can *see* some differences between boards.  I can *feel* some
differences in 
> terms of being able to unsolder or to remove the component or
whatever,  and 
> differences in the weight of the copper,  etc.  But I don't have the 
> experience in making boards to be able to quantify this stuff.


I mechanically etch boards and when I'm done, I peal large sections of
copy off the boards in areas.

FR4 has copper stuck on like bumper stickers.  Some will outlast the
cars...

CM2 looks and acts just like FR4, but the copper peals away in large
sheets.  I think I had some teflon board material when I got the
machine, that stuff pealed very easily and the boards were bright
white and relitivly slipper, and very smooth.

Fiberglass has a rough surface, so the copper has more places to grab
and hold.

The manual for the machine says to drill first, because if you etch a
pad, then drill, the drill can spin the pad off in some cases.

Anyway, from my experiance, I have learned a few things.

#1) use as large a pad as you can, really large if there will be any
mechanical forces later, like heat sinks or screw terminals or headers
or even DIP sockets where one will be removing the chips.

#2) never allow a mechanical thing to be on the same side as the pad
if you will ever pull on it.   The answer to that is to put pads on
both sides and even if you do not plate connect them, solder both sides.

as for the comment about bents pins, I hate people who bend every
other pin of an IC or other component.  PITA when removing.  BUT.... I
have has high current melt solder, or electrolocys or whatever... and
have found components loose in the board.  had they not been bent, the
part would have fallen out.  so, for some boards, I would recomend
that action.  Very rare though.

Dave