Homebrew PCBs

On a different subject entirely,

I am 100% happy with press-n-peel  but there again I don't have to do 
any super fine work. I gave up UV exposure several years ago except 
for etching on curved aluminium castings.

I keep looking at the picture on the group homepage and wince at the 
amount of etchant used to etch those big empty areas....  :-(

I know 99% of the group will already be filling those areas with 
copper, but in case there are any beginners out there, unless there is 
a good reason to remove the big areasof copper,  (like RF work) it is 
more economical to leave as much copper on the board as possible. 

Chris

HI CHris,

I just learned that trick with my software about 2 weeks ago and 
have been doing it every chance I get - that is a good tip!

Chris







--- In Homebrew_PCBs@yahoogroups.com, "Chris Horne" <chris@s...> 
wrote:
>
> On a different subject entirely,
> 
> I am 100% happy with press-n-peel  but there again I don't have to 
do 
> any super fine work. I gave up UV exposure several years ago 
except 
> for etching on curved aluminium castings.
> 
> I keep looking at the picture on the group homepage and wince at 
the 
> amount of etchant used to etch those big empty areas....  :-(
> 
> I know 99% of the group will already be filling those areas with 
> copper, but in case there are any beginners out there, unless 
there is 
> a good reason to remove the big areasof copper,  (like RF work) it 
is 

> more economical to leave as much copper on the board as possible. 
> 
> Chris
>

I agree. Try to keep all of them connected to ground. I usually cheat 
when laying out a board and don't bother with the grounds until I am 
nearly finished. I then do a ground copper pour and sort out any missing 
grounds that are left. It can save quite a bit of time.

Les

Chris Horne wrote:

>On a different subject entirely,
>
>I am 100% happy with press-n-peel  but there again I don't have to do 
>any super fine work. I gave up UV exposure several years ago except 
>for etching on curved aluminium castings.
>
>I keep looking at the picture on the group homepage and wince at the 
>amount of etchant used to etch those big empty areas....  :-(
>
>I know 99% of the group will already be filling those areas with 
>copper, but in case there are any beginners out there, unless there is 
>a good reason to remove the big areasof copper,  (like RF work) it is 
>more economical to leave as much copper on the board as possible. 
>
>Chris
>
>
>
>
>
>
>
>
>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
>
>
>
> 
>
>
>
>
>  
>



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I sometimes make a copper pour, but i'm not very fond of "orphaned" areas  
enclosed by tracks, and deleting them makes the board look very strange  
with copper all round but areas missing.
Since etchant costs almost nothing i don't worry much about it.

ST

On Thu, 17 Nov 2005 17:31:06 +0100, Chris Horne <chris@...> wrote:

> On a different subject entirely,
>
>
> I am 100% happy with press-n-peel  but there again I don't have to do
>
> any super fine work. I gave up UV exposure several years ago except
>
> for etching on curved aluminium castings.
>
>
> I keep looking at the picture on the group homepage and wince at the
>
> amount of etchant used to etch those big empty areas....
>
>
> I know 99% of the group will already be filling those areas with
>
> copper, but in case there are any beginners out there, unless there is
>
> a good reason to remove the big areasof copper,  (like RF work) it is
>
> more economical to leave as much copper on the board as possible.
>
>
> Chris

Stefan Trethan wrote:

>I sometimes make a copper pour, but i'm not very fond of "orphaned" areas  
>enclosed by tracks, and deleting them makes the board look very strange  
>with copper all round but areas missing.
>Since etchant costs almost nothing i don't worry much about it.
>
>ST
>
>
>  
>

  The real reason to do it isn't cost.  Copper is a moderate poison, 
better for it to sit on a board where it does relatively little harm 
than have more back outside.  Also usually helps your board to widen the 
traces, amazing how often .040" traces will be fine..  Just use 2-3 
times the gap around any areas, to make sure they etch well and aren't a 
problem area..  I don't go nuts over it with every little space, but if 
there is a large unused area or two it's reasonable enough to not worry 
about it.

Alan

I agree on the space. If you put the ground too close to pads it can make  
soldering harder, as it easily bridges the gap. I think i've 0.3mm default  
in my software, which is too close.

On the etching side i must say it worked rather well each time. Faster,  
and more even i think. Seems the uniform width lines make for a even etch,  
and the small area for speed.

ST

On Thu, 17 Nov 2005 20:17:13 +0100, Alan King <alan@...> wrote:

>
>
>
>   The real reason to do it isn't cost.  Copper is a moderate poison,
>
> better for it to sit on a board where it does relatively little harm
>
> than have more back outside.  Also usually helps your board to widen the
>
> traces, amazing how often .040" traces will be fine..  Just use 2-3
>
> times the gap around any areas, to make sure they etch well and aren't a
>
> problem area..  I don't go nuts over it with every little space, but if
>
> there is a large unused area or two it's reasonable enough to not worry
>
> about it.
>
>
> Alan

----- Original Message ----- 

From: "lcdpublishing" <lcdpublishing@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Thursday, November 17, 2005 10:58 AM
Subject: [Homebrew_PCBs] Re: Not anything to do with exposure boxes whatever 
!


> HI CHris,
>
> I just learned that trick with my software about 2 weeks ago and
> have been doing it every chance I get - that is a good tip!

Do you tin plate before etching? Either way, it uses either lots of: 
plating, toner, or etchant. Unless you're using photo-resist, in which case 
the extra light is more or less free, and exhausted developer is still 
cheap.

What software? Is it possible in Eagle?

I tin after etching, befor etching would be more difficult in the 
toner transfer process unless you get a perfectly smooth surface.  

The cost of toner is about zero with regard to toner transfer, I am 
quit certain the toner for a circuit board is far less than 1 penny. 
Don't know how it can use "Lot's" of toner, but then again, "Lot's" is 
a relative term.

The etchant cost, I don't know yet how much per board that is.  
However, so far it doesn't appear to be too expensive.

I use PCB Wizard, don't know about Eagle, others may answer that as it 
is very popular.

Chris




> Do you tin plate before etching? Either way, it uses either lots of: 
> plating, toner, or etchant. Unless you're using photo-resist, in 
which case 
> the extra light is more or less free, and exhausted developer is 
still 

> cheap.
> 
> What software? Is it possible in Eagle?
>