Homebrew PCBs

This is odd.  I have been doing toner transfer for almost a year now 
and can get very good results - fairly repeatable.  Since learning 
more and more and since I have run out of the original photo papaer 
I was using, I have been working with two different papers of late.

1) HP Photo paper -glossy
2) Hammermill color laser paper - it's a semi-gloss

Earlier this week I needed to make a board so I selected what I 
thought was the best working paper I had on hand, the Hammermill 
paper.  I printed out the layout and could tell right away there 
were problems as the toner was VERY thin in some areas. So, thinking 
I had it wrong in memory, I then grabbed the HP paper and all went 
well.

As typical for me, I screwed up that PCB (forgot to make some 
changes) so I had to make it again (3 days later than the previous 
attempt).  I grabbed the HP paper, printed out the layout and this 
time it had very thin deposits of toner on the traces.  So, I 
grabbed the Hammermill paper and it worked perfectly.  

The only thing that changed from the first attempt and the second 
attempt is 3 days in time.  Same printer, same cartridge (no, it's 
not low on toner), approximately the same outdoor 
temperature/humidity, and even the same layout for the most part.

So, while I would like to think that toner transfer will work good, 
there are some hidden mysteries to it that seem to make you scratch 
your head in bewilderment!

Chris

--- In Homebrew_PCBs@yahoogroups.com, "lcdpublishing" 
<lcdpublishing@...> wrote:
>
> This is odd.  I have been doing toner transfer for almost a year 
now 
> and can get very good results - fairly repeatable.  Since learning 
> more and more and since I have run out of the original photo papaer 
> I was using, I have been working with two different papers of late.
> 
> 1) HP Photo paper -glossy
> 2) Hammermill color laser paper - it's a semi-gloss
> 
> Earlier this week I needed to make a board so I selected what I 
> thought was the best working paper I had on hand, the Hammermill 
> paper.  I printed out the layout and could tell right away there 
> were problems as the toner was VERY thin in some areas. So, 
thinking 
> I had it wrong in memory, I then grabbed the HP paper and all went 
> well.
> 
> As typical for me, I screwed up that PCB (forgot to make some 
> changes) so I had to make it again (3 days later than the previous 
> attempt).  I grabbed the HP paper, printed out the layout and this 
> time it had very thin deposits of toner on the traces.  So, I 
> grabbed the Hammermill paper and it worked perfectly.  
> 
> The only thing that changed from the first attempt and the second 
> attempt is 3 days in time.  Same printer, same cartridge (no, it's 
> not low on toner), approximately the same outdoor 
> temperature/humidity, and even the same layout for the most part.
> 
> So, while I would like to think that toner transfer will work good, 
> there are some hidden mysteries to it that seem to make you scratch 
> your head in bewilderment!
> 
> Chris
>


I vaguely remember hearing or reading somewhere, (I can't say 
that it was on this list / group) that in order to get reliable & 
consistent results with thick even toner distribution you first 
needed to run a couple of pages thru the printer. From what 
I recall it did not need to be a heavy coverage print, even 
moderate text would do. I ran a couple of 'printer test / self test' 
pages thru before attempting my next TT job (from a dead cold/ turned 
off for days printer) and it seemed to improve results, or maybe I 
just convinced myself it at the time. Something about warming up the 
entire printer and dissipating / averaging stray static charges. On 
the other hand  the whole thing could have been a load of B.S. 
(But not on my part)I've been low on toner in my HP4v for while now, 
so I've been using up my stock of photo resist board. Been a long 
time been a long since I did any TT boards.