Homebrew PCBs

Richard Mcfarlane wrote:

>Dear Moderator Mr. Curtis Richards,
> Many thanks for your useful EDM  information.
>I like to buy one of the EDM books you mentioned
>below.Which one would be better? I wish to build a CNC
>Wire /Sinker EDM with PWM- EDM Power Supply:-
>1. How to EDM Book--By Mr.Ben Fleming (20 USD)
>2. S-EDM for the Homeshop--By Practice Publication 
>    Price -Not mentioned and from where to get this
>book?Is this the very same EDM(Robert Langlois) book
>by Home Shop Machinist? I have this book.But this is
>not a CNC EDM.
> Please let me know.
>Regards.
>Richard.
>  
>
Hi again Richard,

On RE-reading your e-mail I realize I didn't really answer your main question.  If you are looking to build a wire EDM which will cut parts from DXF or DWG files, you will be best served with the Fleming book with its instructions for building a tank, servo EDM head and general info on EDM.  You will want to build the Garden of EDM power supply (a PWM high amperage supply).  When it comes to a machine base you going to have to adapt the transport from another system.

You could use something like 3 roller belt sander configuration for the wire transport and a xy CNC table to hold your raw material ( maybe something like the ENCO 8x18 milling table with steppers fitted and driven by EMC on an old 486 or Pentium? ).

I should have my PCB burner finished by Labor Day weekend, but I am not sure how much use it will be for a wire EDM.  The gap is controlled by the  voltage at which the dielectric breaks down which should be adaptable to the Fleming servo system  and the xy movement is controlled by a PIC with a canned stepper control program ( see Microchip AN822 and AN906 ).

I'm mostly concentrating on getting my 1954 Jeep on the road, but I'll publish my EDM results on Homebrew_PCBs as they develop.


-- 
Curtis W Richards

--

"The natural progress of things is for liberty 
 to yield and government to gain ground."
 --Thomas Jefferson

I see no reason to use EDM for PCB mechanical etching. It sounds 
like an insane idea.  Mike


--- In Homebrew_PCBs@yahoogroups.com, Curtis Richards <cwrxr@e...> 
wrote:
> Richard Mcfarlane wrote:
> 
> >Dear Moderator Mr. Curtis Richards,
> > Many thanks for your useful EDM  information.
> >I like to buy one of the EDM books you mentioned
> >below.Which one would be better? I wish to build a CNC
> >Wire /Sinker EDM with PWM- EDM Power Supply:-
> >1. How to EDM Book--By Mr.Ben Fleming (20 USD)
> >2. S-EDM for the Homeshop--By Practice Publication 
> >    Price -Not mentioned and from where to get this
> >book?Is this the very same EDM(Robert Langlois) book
> >by Home Shop Machinist? I have this book.But this is
> >not a CNC EDM.
> > Please let me know.
> >Regards.
> >Richard.
> >  
> >
> Hi again Richard,
> 
> On RE-reading your e-mail I realize I didn't really answer your 
main question.  If you are looking to build a wire EDM which will 
cut parts from DXF or DWG files, you will be best served with the 
Fleming book with its instructions for building a tank, servo EDM 
head and general info on EDM.  You will want to build the Garden of 
EDM power supply (a PWM high amperage supply).  When it comes to a 
machine base you going to have to adapt the transport from another 
system.
> 
> You could use something like 3 roller belt sander configuration 
for the wire transport and a xy CNC table to hold your raw material 
( maybe something like the ENCO 8x18 milling table with steppers 
fitted and driven by EMC on an old 486 or Pentium? ).
> 
> I should have my PCB burner finished by Labor Day weekend, but I 
am not sure how much use it will be for a wire EDM.  The gap is 
controlled by the  voltage at which the dielectric breaks down which 
should be adaptable to the Fleming servo system  and the xy movement 
is controlled by a PIC with a canned stepper control program ( see 
Microchip AN822 and AN906 ).
> 
> I'm mostly concentrating on getting my 1954 Jeep on the road, but 
I'll publish my EDM results on Homebrew_PCBs as they develop.

> 
> 
> -- 
> Curtis W Richards
> 
> --
> 
> "The natural progress of things is for liberty 
>  to yield and government to gain ground."
>  --Thomas Jefferson

Hi,

>I see no reason to use EDM for PCB mechanical etching. It sounds
> like an insane idea.  Mike

    Why ???!!

    If Curtis description is precise it would be a great method for many 
people !!! I am one of them... A machine with no cutting forces acting is 
much easier to make and maintain and EDM would also be cleaner and cheaper 
because you would not have dust and no mills to buy !!

    Curtis, could you send us some pictures of the boards you made and the 
"EDM head" setup ?? I am very, very curious about it...

Best regards,
Alexandre Guimaraes

On 8/3/05, mikezcnc <eemikez@...> wrote:
> I see no reason to use EDM for PCB mechanical etching. It sounds
> like an insane idea.  Mike

You should be able to get much finer traces using EDM than you can get
using toner transfer. With some decent software to move the head
faster when it doesn't need to erode away any copper would make it
fairly quick too.

I think its a great idea.

-- 
Dave Hylands
Vancouver, BC, Canada
http://www.DaveHylands.com/

but then it wouldn't create all that dust, noise and cutter wear. 
what's the fun in that?

--- In Homebrew_PCBs@yahoogroups.com, Dave Hylands <dhylands@g...> wrote:

> On 8/3/05, mikezcnc <eemikez@c...> wrote:
> > I see no reason to use EDM for PCB mechanical etching. It sounds
> > like an insane idea.  Mike
> 
> You should be able to get much finer traces using EDM than you can get
> using toner transfer. With some decent software to move the head
> faster when it doesn't need to erode away any copper would make it
> fairly quick too.
> 
> I think its a great idea.
> 
> -- 
> Dave Hylands
> Vancouver, BC, Canada
> http://www.DaveHylands.com/

I've thought about PCB etching with EDM, I figured it would work ok, but
be a bit slow.

People mill PCBs, that's slow & noisy!  At least EDM is quiet.

Considering the small amount of material you need to remove, the results
might surprise you.  After all, electricity is a good way of removing
metal.  Most of us have screwdrivers or probes with bits missing (usually
after testing capacitors!), that's a good bit of metal removed in a short
time.

I'd be interested in the final result (quality, speed, minimum trace etc),
but I doubt I'll ever make PCBs this way, but I'm happy to keep it in
mind.  The info could come in handy for other projects, etching
nameplates, etc.

Tony

>     I see no reason to use EDM for PCB mechanical etching. It sounds
>  like an insane idea.  Mike
>
>
>  --- In Homebrew_PCBs@yahoogroups.com, Curtis Richards
>  wrote:
>  > Richard Mcfarlane wrote:
>  >
>  > >Dear Moderator Mr. Curtis Richards,
>  > > Many thanks for your useful EDM  information.
>  > >I like to buy one of the EDM books you mentioned
>  > >below.Which one would be better? I wish to build a CNC
>  > >Wire /Sinker EDM with PWM- EDM Power Supply:-
>  > >1. How to EDM Book--By Mr.Ben Fleming (20 USD)
>  > >2. S-EDM for the Homeshop--By Practice Publication
>  > >    Price -Not mentioned and from where to get this
>  > >book?Is this the very same EDM(Robert Langlois) book
>  > >by Home Shop Machinist? I have this book.But this is

On Thu, 04 Aug 2005 04:06:25 +0200, mikezcnc <eemikez@...> wrote:

> I see no reason to use EDM for PCB mechanical etching. It sounds
> like an insane idea.  Mike


less insane than using a spinning stick of carbide with grooves in it to  
knock out copper pieces and bits of board, for sure!

Why is it insane in your opinion?


ST

--- In Homebrew_PCBs@yahoogroups.com, "mikezcnc" <eemikez@c...> 
wrote:
> I see no reason to use EDM for PCB mechanical etching. It sounds 
> like an insane idea.  Mike

Why is that Mike?

While I love cutting metal with a variety of machines, I don't see 
why using EDM would be bad for this application.  It could be a 
relatively fast process provided the power supply and electrodes are 
worked out properly.  The programming process that one fellow has 
proposed is to work from a bitmap image which means 
the "programming" would be fast and easy.  Wouldn't require any 
software to create the mill paths.

So, as much as I love cutting metal, I am just as eager to burn it.

However, ideally, what I would love to see is an additive process as 
opposed to subtractive.  In other words, instead of removing copper 
where we don't want it (thus wasting the resource), applying the 
copper to where we need it - much more resource responsible.  

Some chemist somewhere has got to figure out a way to make copper 
into a liquid form that can be "painted" onto a circuit board and 
make it stick there.  This would be the ideal method in my opinion 
as it wouldn't waste resources (Copper), it would be efficient (not 
adding something and then remmoving it), and it should be easy to 
make a CNC machine apply the copper traces (using a wide variety of 
in-expensive software).

So, I guess my perspective is that chemical etching or cutting away 
the copper is insane ;-)

Chris