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G-10 questions

G-10 questions

2015-09-29 by Brad

Hi guys,

 

I've been continuing to research and amass parts for my TV Typewriter
replica build.  I have a blog of it here: http://bradhodge.ca/blog  --
mostly working on the case right now to inspire me to push forward, but I've
succeeded in getting almost all of the vintage 1973 or earlier chips I
needed.  Now I'm down to the PCBs again.

 

I guess I'm still kind of 'green' on this sort of thing.  Ideally, I'd like
to do my PCBs the way they would have in 1973.  But I still don't understand
how that worked.  Don Lancaster said the boards used were green G-10.  I
found this on ebay:
http://www.ebay.com/itm/16-Green-G-10-FR4-Sheets-032-Thick-x-28-x-7-25-G10-M
aterial-/141719358328?hash=item20ff21cb78

 

I guess what I'm having trouble with is understanding how a home PCB maker
in 1973 would have gone about getting copper onto these boards and copying
the artwork from the article.  Is there any really good, baby-steps reading
out there?  I just want to understand the original process and if it is
possible to replicate it here in 2015.  I sort of understand the idea behind
photo lithography.. I'm just not understanding how copper ends up on board,
etc.

 

Much appreciated!

 

BRad

Re: [Homebrew_PCBs] G-10 questions

2015-09-29 by Malcolm Parker-Lisberg

Back in those days I used two methods:
Copper clad FR4 was available, but a lot of SRBP was used as it was much cheaper.
The first method was to paint, by hand, using mothers thinned nail varnish onto a carbon paper print traced from the layout printout.
There was a great negative photo resist, KPCR, made by Kodak, sadly no longer available that you exposed to ultra violet light through a negative transparency of the of the layout.
Then developed in a solvent based solution that coloured your fingers red for at least a week if you got it on them.

So you would not be cheating if you used modern pre-sensitized copper FR4 from companies such as Mega,
<http://www.megauk.com/pcb_laminates.php>
or a dry film:
<http://www.instructables.com/id/Fantastic-Double-Sided-PCBs-at-home-using-photores/>
or
<https://www.youtube.com/watch?v=cRCFGZxmob0>

Malcolm

I don't suffer from insanity I enjoy it!
Mene, mene, tekel, upharsin
The writing is on the wall.
Ha-ktovet al ha-kir

--------------------------------------------
On Tue, 9/29/15, 'Brad' unclefalter@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
Show quoted textHide quoted text
 Subject: [Homebrew_PCBs] G-10 questions
 To: Homebrew_PCBs@yahoogroups.com
 Date: Tuesday, September 29, 2015, 11:51 PM
 
 
  
 
 
 
   
 
 
     
       
       
       Hi guys,  I’ve been continuing to
 research and amass parts for my TV Typewriter replica build.
  I have a blog of it here: http://bradhodge.ca/blog 
 -- mostly working on the case right now to inspire me to
 push forward, but I’ve succeeded in getting almost all of
 the vintage 1973 or earlier chips I needed.  Now I’m down
 to the PCBs again.
  I guess I’m still
 kind of ‘green’ on this sort of thing.  Ideally, I’d
 like to do my PCBs the way they would have in 1973.  But I
 still don’t understand how that worked.  Don Lancaster
 said the boards used were green G-10.  I found this on
 ebay:  http://www.ebay.com/itm/16-Green-G-10-FR4-Sheets-032-Thick-x-28-x-7-25-G10-Material-/141719358328?hash=item20ff21cb78  I guess what I’m having trouble
 with is understanding how a home PCB maker in 1973 would
 have gone about getting copper onto these boards and copying
 the artwork from the article.  Is there any really good,
 baby-steps reading out there?  I just want to understand
 the original process and if it is possible to replicate it
 here in 2015.  I sort of understand the idea behind photo
 lithography.. I’m just not understanding how copper ends
 up on board, etc.  Much appreciated!  BRad     
 
     
      
 
     
     
 
 
 
 #yiv0643880995 #yiv0643880995 --

RE: [Homebrew_PCBs] G-10 questions

2015-09-30 by Brad

Thanks muchly Malcolm.  That makes things a lot clearer.

 

Question – did you do any silkscreening back then for parts placement?  I notice in the plans printed by Radio Electronics, they had the printouts for the copper side, but also silkscreening for the non-copper side to aid in parts placement.  I’m wondering how a home hobbyist at the time might have pulled that off, or if they did.
Show quoted textHide quoted text
From: Homebrew_PCBs@...m [mailto:Homebrew_PCBs@yahoogroups.com] 
Sent: Tuesday, September 29, 2015 4:15 PM
To: Homebrew_PCBs@yahoogroups.com
Subject: Re: [Homebrew_PCBs] G-10 questions

 

  

Back in those days I used two methods:
Copper clad FR4 was available, but a lot of SRBP was used as it was much cheaper.
The first method was to paint, by hand, using mothers thinned nail varnish onto a carbon paper print traced from the layout printout.
There was a great negative photo resist, KPCR, made by Kodak, sadly no longer available that you exposed to ultra violet light through a negative transparency of the of the layout.
Then developed in a solvent based solution that coloured your fingers red for at least a week if you got it on them.

So you would not be cheating if you used modern pre-sensitized copper FR4 from companies such as Mega,
<http://www.megauk.com/pcb_laminates.php>
or a dry film:
<http://www.instructables.com/id/Fantastic-Double-Sided-PCBs-at-home-using-photores/>
or
<https://www.youtube.com/watch?v=cRCFGZxmob0>

Malcolm

I don't suffer from insanity I enjoy it!
Mene, mene, tekel, upharsin
The writing is on the wall.
Ha-ktovet al ha-kir

--------------------------------------------
On Tue, 9/29/15, 'Brad' unclefalter@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:

Subject: [Homebrew_PCBs] G-10 questions
To: Homebrew_PCBs@yahoogroups.com
Date: Tuesday, September 29, 2015, 11:51 PM


 









Hi guys,  I’ve been continuing to
research and amass parts for my TV Typewriter replica build.
 I have a blog of it here: http://bradhodge.ca/blog 
-- mostly working on the case right now to inspire me to
push forward, but I’ve succeeded in getting almost all of
the vintage 1973 or earlier chips I needed.  Now I’m down
to the PCBs again.
 I guess I’m still
kind of ‘green’ on this sort of thing.  Ideally, I’d
like to do my PCBs the way they would have in 1973.  But I
still don’t understand how that worked.  Don Lancaster
said the boards used were green G-10.  I found this on
ebay:  http://www.ebay.com/itm/16-Green-G-10-FR4-Sheets-032-Thick-x-28-x-7-25-G10-Material-/141719358328?hash=item20ff21cb78  I guess what I’m having trouble
with is understanding how a home PCB maker in 1973 would
have gone about getting copper onto these boards and copying
the artwork from the article.  Is there any really good,
baby-steps reading out there?  I just want to understand
the original process and if it is possible to replicate it
here in 2015.  I sort of understand the idea behind photo
lithography.. I’m just not understanding how copper ends
up on board, etc.  Much appreciated!  BRad     









#yiv0643880995 #yiv0643880995 --

Re: [Homebrew_PCBs] G-10 questions

2015-09-30 by Leon Heller

On 30/09/2015 00:14, Malcolm Parker-Lisberg mparkerlisberg@... 
[Homebrew_PCBs] wrote:
> Back in those days I used two methods:
> Copper clad FR4 was available, but a lot of SRBP was used as it was much
> cheaper.

A resist-coated fibre glass and paper composite (FPC 16) is available 
from Mega Electronics UK:

http://www.megauk.com/pcb_laminates.php

I used to use it rather than FR4 as it was *much* easier to cut and 
drill, as well as being cheaper.

Leon
-- 
Leon Heller
G1HSM

RE: [Homebrew_PCBs] G-10 questions

2015-09-30 by Malcolm Parker-Lisberg

Brad

The simple answer is no.  Laser printers did not exist then so toner transfer was not possible.  Silk screen materials were available and you could do a screen if you had access to a college art department.

Again you could cheat by doing a colour laser printout thermal transfer.  You  need some means of aligning the image to the board.

Malcolm

I don't suffer from insanity I enjoy it!
Mene, mene, tekel, upharsin
The writing is on the wall.
Ha-ktovet al ha-kir

--------------------------------------------
On Wed, 9/30/15, 'Brad' unclefalter@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
Show quoted textHide quoted text
 Subject: RE: [Homebrew_PCBs] G-10 questions
 To: Homebrew_PCBs@yahoogroups.com
 Date: Wednesday, September 30, 2015, 5:51 AM
 
 
  
 
 
 
   
 
 
     
       
       
       Thanks muchly Malcolm.  That
 makes things a lot clearer.  Question – did you do any
 silkscreening back then for parts placement?  I notice in
 the plans printed by Radio Electronics, they had the
 printouts for the copper side, but also silkscreening for
 the non-copper side to aid in parts placement.  I’m
 wondering how a home hobbyist at the time might have pulled
 that off, or if they did.  From: Homebrew_PCBs@yahoogroups.com
 [mailto:Homebrew_PCBs@yahoogroups.com] 
 Sent: Tuesday, September 29, 2015 4:15
 PM
 To:
 Homebrew_PCBs@yahoogroups.com
 Subject: Re: [Homebrew_PCBs] G-10
 questions    Back in those days I used two
 methods:
 Copper clad FR4 was available, but
 a lot of SRBP was used as it was much cheaper.
 The first method was to paint, by hand, using
 mothers thinned nail varnish onto a carbon paper print
 traced from the layout printout.
 There was a
 great negative photo resist, KPCR, made by Kodak, sadly no
 longer available that you exposed to ultra violet light
 through a negative transparency of the of the layout.
 Then developed in a solvent based solution that
 coloured your fingers red for at least a week if you got it
 on them.
 
 So you would not
 be cheating if you used modern pre-sensitized copper FR4
 from companies such as Mega,
 <http://www.megauk.com/pcb_laminates.php>
 or a dry film:
 <http://www.instructables.com/id/Fantastic-Double-Sided-PCBs-at-home-using-photores/>
 or
 <https://www.youtube.com/watch?v=cRCFGZxmob0>
 
 Malcolm
 
 I don't suffer from insanity I enjoy it!
 Mene, mene, tekel, upharsin
 The
 writing is on the wall.
 Ha-ktovet al
 ha-kir
 
 --------------------------------------------
 On Tue, 9/29/15, 'Brad'
 unclefalter@... [Homebrew_PCBs]
 <Homebrew_PCBs@yahoogroups.com> wrote:
 
 Subject: [Homebrew_PCBs] G-10
 questions
 To:
 Homebrew_PCBs@yahoogroups.com
 Date: Tuesday,
 September 29, 2015, 11:51 PM
 
 
  
 
 
 
 
 
 
 
 
 
 Hi guys,
  I’ve been continuing to
 research and
 amass parts for my TV Typewriter replica build.
  I have a blog of it here:
 http://bradhodge.ca/blog 
 -- mostly working
 on the case right now to inspire me to
 push
 forward, but I’ve succeeded in getting almost all of
 the vintage 1973 or earlier chips I needed. 
 Now I’m down
 to the PCBs again.
  I guess I’m still
 kind of
 ‘green’ on this sort of thing.  Ideally, I’d
 like to do my PCBs the way they would have in
 1973.  But I
 still don’t understand how
 that worked.  Don Lancaster
 said the boards
 used were green G-10.  I found this on
 ebay: 
 http://www.ebay.com/itm/16-Green-G-10-FR4-Sheets-032-Thick-x-28-x-7-25-G10-Material-/141719358328?hash=item20ff21cb78
  I guess what I’m having trouble
 with is
 understanding how a home PCB maker in 1973 would
 have gone about getting copper onto these
 boards and copying
 the artwork from the
 article.  Is there any really good,
 baby-steps reading out there?  I just want to
 understand
 the original process and if it is
 possible to replicate it
 here in 2015.  I
 sort of understand the idea behind photo
 lithography.. I’m just not understanding how
 copper ends
 up on board, etc.  Much
 appreciated!  BRad     
 
 
 
 
 
 
 
 
 
 #yiv0643880995 #yiv0643880995 --

RE: [Homebrew_PCBs] G-10 questions

2015-09-30 by Dave G4UGM

When did etch resist pens come in? Pretty sure they were around in 1972. 
Show quoted textHide quoted text
> -----Original Message-----
> From: Homebrew_PCBs@yahoogroups.com
> [mailto:Homebrew_PCBs@yahoogroups.com]
> Sent: 30 September 2015 10:40
> To: Homebrew_PCBs@yahoogroups.com
> Subject: RE: [Homebrew_PCBs] G-10 questions
> 
> Brad
> 
> The simple answer is no.  Laser printers did not exist then so toner transfer
> was not possible.  Silk screen materials were available and you could do a
> screen if you had access to a college art department.
> 
> Again you could cheat by doing a colour laser printout thermal transfer.  You
> need some means of aligning the image to the board.
> 
> Malcolm
> 
> I don't suffer from insanity I enjoy it!
> Mene, mene, tekel, upharsin
> The writing is on the wall.
> Ha-ktovet al ha-kir
> 
> --------------------------------------------
> On Wed, 9/30/15, 'Brad' unclefalter@... [Homebrew_PCBs]
> <Homebrew_PCBs@yahoogroups.com> wrote:
> 
>  Subject: RE: [Homebrew_PCBs] G-10 questions
>  To: Homebrew_PCBs@yahoogroups.com
>  Date: Wednesday, September 30, 2015, 5:51 AM
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
>        Thanks muchly Malcolm.  That
>  makes things a lot clearer.  Question – did you do any  silkscreening back
> then for parts placement?  I notice in  the plans printed by Radio Electronics,
> they had the  printouts for the copper side, but also silkscreening for  the
> non-copper side to aid in parts placement.  I’m  wondering how a home
> hobbyist at the time might have pulled  that off, or if they did.  From:
> Homebrew_PCBs@yahoogroups.com
> [mailto:Homebrew_PCBs@yahoogroups.com]
>  Sent: Tuesday, September 29, 2015 4:15
>  PM
>  To:
>  Homebrew_PCBs@...m
>  Subject: Re: [Homebrew_PCBs] G-10
>  questions    Back in those days I used two
>  methods:
>  Copper clad FR4 was available, but
>  a lot of SRBP was used as it was much cheaper.
>  The first method was to paint, by hand, using  mothers thinned nail varnish
> onto a carbon paper print  traced from the layout printout.
>  There was a
>  great negative photo resist, KPCR, made by Kodak, sadly no  longer available
> that you exposed to ultra violet light  through a negative transparency of the
> of the layout.
>  Then developed in a solvent based solution that  coloured your fingers red
> for at least a week if you got it  on them.
> 
>  So you would not
>  be cheating if you used modern pre-sensitized copper FR4  from companies
> such as Mega,  <http://www.megauk.com/pcb_laminates.php>
>  or a dry film:
>  <http://www.instructables.com/id/Fantastic-Double-Sided-PCBs-at-home-
> using-photores/>
>  or
>  <https://www.youtube.com/watch?v=cRCFGZxmob0>
> 
>  Malcolm
> 
>  I don't suffer from insanity I enjoy it!
>  Mene, mene, tekel, upharsin
>  The
>  writing is on the wall.
>  Ha-ktovet al
>  ha-kir
> 
>  --------------------------------------------
>  On Tue, 9/29/15, 'Brad'
>  unclefalter@... [Homebrew_PCBs]
>  <Homebrew_PCBs@yahoogroups.com> wrote:
> 
>  Subject: [Homebrew_PCBs] G-10
>  questions
>  To:
>  Homebrew_PCBs@yahoogroups.com
>  Date: Tuesday,
>  September 29, 2015, 11:51 PM
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
>  Hi guys,
>   I’ve been continuing to
>  research and
>  amass parts for my TV Typewriter replica build.
>   I have a blog of it here:
>  http://bradhodge.ca/blog
>  -- mostly working
>  on the case right now to inspire me to
>  push
>  forward, but I’ve succeeded in getting almost all of  the vintage 1973 or
> earlier chips I needed.  Now I’m down  to the PCBs again.
>   I guess I’m still
>  kind of
>  ‘green’ on this sort of thing.  Ideally, I’d  like to do my PCBs the way they
> would have in  1973.  But I  still don’t understand how  that worked.  Don
> Lancaster  said the boards  used were green G-10.  I found this on
>  ebay:
>  http://www.ebay.com/itm/16-Green-G-10-FR4-Sheets-032-Thick-x-28-x-7-
> 25-G10-Material-/141719358328?hash=item20ff21cb78
>   I guess what I’m having trouble
>  with is
>  understanding how a home PCB maker in 1973 would  have gone about
> getting copper onto these  boards and copying  the artwork from the
> article.  Is there any really good,  baby-steps reading out there?  I just want to
> understand  the original process and if it is  possible to replicate it  here in
> 2015.  I  sort of understand the idea behind photo  lithography.. I’m just not
> understanding how  copper ends  up on board, etc.  Much
> appreciated!  BRad
> 
> 
> 
> 
> 
> 
> 
> 
> 
>  #yiv0643880995 #yiv0643880995 --
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> ------------------------------------
> Posted by: Malcolm Parker-Lisberg <mparkerlisberg@...>
> ------------------------------------
> 
> Be sure to visit the group home and check for new Links, Files, and Photos:
> http://groups.yahoo.com/group/Homebrew_PCBs
> ------------------------------------
> 
> Yahoo Groups Links
> 
> 
>

Re: [Homebrew_PCBs] G-10 questions

2015-09-30 by Will

I used to do the same, using Humbrol model paint on carbon paper trace. 
For simple things I would paint direct on SRBP. No glass fibre.


Cheers,
Will


On 30/09/15 12:14, Malcolm Parker-Lisberg mparkerlisberg@...
[Homebrew_PCBs] wrote:
Show quoted textHide quoted text
>  
>
> Back in those days I used two methods:
> Copper clad FR4 was available, but a lot of SRBP was used as it was
> much cheaper.
> The first method was to paint, by hand, using mothers thinned nail
> varnish onto a carbon paper print traced from the layout printout.
>
>
>  
>

Re: [Homebrew_PCBs] G-10 questions

2015-09-30 by Leon Heller

On 30/09/2015 10:53, 'Dave G4UGM' dave.g4ugm@... [Homebrew_PCBs] 
wrote:
> When did etch resist pens come in? Pretty sure they were around in 1972.

I vaguely remember using a Decon Dalo pen around then (they are still 
available), but I could be wrong. I found that cellulose paint made 
easier to use by mixing it with thinners worked better, and was much 
cheaper.

Leon
-- 
Leon Heller
G1HSM

Re: G-10 questions

2015-09-30 by palciatore@...

OK, I made PC boards in my garage back in the 70s. I used a variety of techniques.

First, you wonder how the copper got on the boards. Well, even back in those dark ages, you just bought them that way. The factory put the copper on them: I never even considered the possibility of doing it myself. Oh, they did sell pens that drew conductive lines, but I never trusted them so I did not even try them. It was a conductive paint, not solid copper.

You could buy either plain copper clad boards or sensitized copper clad boards. The sensitized ones had the photo resist already sprayed on them in a nice even coat. You needed a high density negative or positive, depending on the type of resist on the board. It was before the days of inexpensive computer CAD so I made 2 times actual size layouts using graph paper with a 1/10th grid of "drop out" lines. That means the lines did not get picked up on the negative or positive transparency which was the next step. I used drafting aids like black adhesive tape in various line widths and self adhesive doughnut pads and IC patterns. All of these were available from drafting supply stores. I carefully placed them on the grid with due care for trace separation. My primary tool was an Xacto knife.

Then that artwork was taken to a drafting or blueprint company who had a copy camera. That was a camera that had the lens, film holder, and art holders all mounted on floor tracks. It could make negatives or positives in exact geometric ratios. Since my original was 2X, I had 1/2 size negatives made. Of course, you could make your own negatives but then you had to work with 1X artwork on transparent plastic and a contact print frame.

Then the boards were exposed to either direct sunlight or a bulb that had heavy IR content in it's light. They were developed using a solvent solution and allowed to dry. Then placed in an etchant until the excess copper was removed. Then the resist was scrubbed off with steel wool or dissolved with a different solvent.

I also liked to use a tin plating solution to improve the solderability. Dip, wait two minutes, remove and rinse.

Finally, they were drilled with the various sized drills needed for the individual pads.

Or you could buy the plain boards and spray the resist on from spray cans. A company called Kepro had all these supplies, but they no longer exist.

Or you could use those self adhesive pads directly on the bare copper board to form the pattern on. This was OK for a one-off board, but tedious if you needed several. And the etchant could get under the traces where they overlapped a doughnut hole due to the height of that doughnut pad.

Another way was to start with the bare copper board (one side or two) and use a perf board to mark the pad locations. Then drill them. Then use a resist pen or a Sharpie marker to draw the foil pattern. Etch, clean, tin plate and use.

Others used other techniques. You could make a Zerox copy of the artwork and use an iron to transfer the toner to the bare copper board. I believe some people still do this today. Some retouching with a resist pen or Sharpie was generally needed.

Like I said, many ways, even back in that ancient era of the 70s.

I assume you are trying to do this in an authentic manner, but back in the 70s I usually saved the PCB process for boards where I needed four or more identical boards. If I only needed one, two, or three I usually used the Vector slit and wrap, wire wrap pens. I built many professional projects that way. I made wire lists and was very careful in making the connections properly. I never had a bad WW board.

Paul A.

Re: [Homebrew_PCBs] Re: G-10 questions

2015-09-30 by Malcolm Parker-Lisberg

Paul
Just to correct your statement
"Then the boards were exposed to either direct sunlight or a bulb that had heavy IR content in it's light."

The resist is not sensitive to infra red (IR), it is sensitive to ultraviolet (UV).

Malcolm


I don't suffer from insanity I enjoy it!
Mene, mene, tekel, upharsin
The writing is on the wall.
Ha-ktovet al ha-kir

--------------------------------------------
On Wed, 9/30/15, palciatore@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
Show quoted textHide quoted text
 Subject: [Homebrew_PCBs] Re: G-10 questions
 To: Homebrew_PCBs@yahoogroups.com
 Date: Wednesday, September 30, 2015, 2:30 PM
 
 
  
 
 
 
   
 
 
     
       
       
       OK, I made PC boards in my garage back in the 70s.
 I used a variety of techniques. 
 
 First, you wonder how the copper got on the
 boards. Well, even back in those dark ages, you just bought
 them that way. The factory put the copper on them: I never
 even considered the possibility of doing it myself. Oh, they
 did sell pens that drew conductive lines, but I never
 trusted them so I did not even try them. It was a conductive
 paint, not solid copper. 
 
 You could buy either plain copper clad boards
 or sensitized copper clad boards. The sensitized ones had
 the photo resist already sprayed on them in a nice even
 coat. You needed a high density negative or positive,
 depending on the type of resist on the board. It was before
 the days of inexpensive computer CAD so I made 2 times
 actual size layouts using graph paper with a 1/10th grid of
 "drop out" lines. That means the lines did not get
 picked up on the negative or positive transparency which was
 the next step. I used drafting aids like black adhesive tape
 in various line widths and self adhesive doughnut pads and
 IC patterns. All of these were available from drafting
 supply stores. I carefully placed them on the grid with due
 care for trace separation. My primary tool was an Xacto
 knife. 
 
 Then that artwork
 was taken to a drafting or blueprint company who had a copy
 camera. That was a camera that had the lens, film holder,
 and art holders all mounted on floor tracks. It could make
 negatives or positives in exact geometric ratios. Since my
 original was 2X, I had 1/2 size negatives made. Of course,
 you could make your own negatives but then you had to work
 with 1X artwork on transparent plastic and a contact print
 frame. 
 
 Then the boards
 were exposed to either direct sunlight or a bulb that had
 heavy IR content in it's light. They were developed
 using a solvent solution and allowed to dry. Then placed in
 an etchant until the excess copper was removed. Then the
 resist was scrubbed off with steel wool or dissolved with a
 different solvent. 
 
 I also
 liked to use a tin plating solution to improve the
 solderability. Dip, wait two minutes, remove and rinse. 
 
 Finally, they were drilled
 with the various sized drills needed for the individual
 pads. 
 
 Or you could buy the
 plain boards and spray the resist on from spray cans. A
 company called Kepro had all these supplies, but they no
 longer exist. 
 
 Or you could
 use those self adhesive pads directly on the bare copper
 board to form the pattern on. This was OK for a one-off
 board, but tedious if you needed several. And the etchant
 could get under the traces where they overlapped a doughnut
 hole due to the height of that doughnut pad. 
 
 Another way was to start with
 the bare copper board (one side or two) and use a perf board
 to mark the pad locations. Then drill them. Then use a
 resist pen or a Sharpie marker to draw the foil pattern.
 Etch, clean, tin plate and use. 
 
 Others used other techniques. You could make a
 Zerox copy of the artwork and use an iron to transfer the
 toner to the bare copper board. I believe some people still
 do this today. Some retouching with a resist pen or Sharpie
 was generally needed. 
 
 Like
 I said, many ways, even back in that ancient era of the 70s.
 
 
 I assume you are trying to
 do this in an authentic manner, but back in the 70s I
 usually saved the PCB process for boards where I needed four
 or more identical boards. If I only needed one, two, or
 three I usually used the Vector slit and wrap, wire wrap
 pens. I built many professional projects that way. I made
 wire lists and was very careful in making the connections
 properly. I never had a bad WW board. 
 
 Paul A.
 
     
      
 
     
     
 
 
 
 #yiv9643158145 #yiv9643158145 --

Re: [Homebrew_PCBs] G-10 questions

2015-09-30 by Corey Minion

in the 70s as a jr high and high school teenager I used tshirt silk 
screen kits from the craft/toy store with staedler mars drafting pens on 
overhead projector transparencies and a photoflood to make traces and 
screens.
College art department?
basement laundry room.


Used to get linotape then too from the papergoods/office supply stores 
in the malls, but that risked shadows from the second clear layer.




On 9/30/2015 5:39 AM, Malcolm Parker-Lisberg mparkerlisberg@... 
[Homebrew_PCBs] wrote:
Show quoted textHide quoted text
> Brad
>
> The simple answer is no.  Laser printers did not exist then so toner transfer was not possible.  Silk screen materials were available and you could do a screen if you had access to a college art department.
>
> Again you could cheat by doing a colour laser printout thermal transfer.  You  need some means of aligning the image to the board.
>
> Malcolm
>
> I don't suffer from insanity I enjoy it!
> Mene, mene, tekel, upharsin
> The writing is on the wall.
> Ha-ktovet al ha-kir
>
>

Re: G-10 questions

2015-09-30 by roger@...

I also built boards in the early years. One of the spray on resists was produced by a company called Dynachem. It was a system that required a solvent developer and a dye to color it so you could see what was going on. Going by the odor of the product, it was probably the same product later sold through GC Electronics with the dye added to the resist. Bishop graphics made the the stick on pattters for the tape up artwork. They patterns were available in 1X, 2X and larger IIIRC. I had a camera lens I picked up at a surplus store and made my own setup for 2X artwork and used Kodalith sheet film for the negatives. The spray on resist gave me inconsistant results, probably more my fault than the products fault. There was also a dry transfer product that used rub-on patterns and traced. There were also dry transfer letters for labels on projects. I still have some of the G10 copper clad material from that era never used it all.

RE: [Homebrew_PCBs] G-10 questions

2015-10-01 by Brad

Thanks guys.  I’ll tell you why I’m wondering about this.  Recently I missed, by inches, an auction on ebay that offered supposedly original SWTPC TV Typewriter boards.  Here’s a couple pictures of them:

 

http://s1381.photobucket.com/user/unclefalter/media/tvtboards2_zpssy81hx8b.jpg.html?sort=3 <http://s1381.photobucket.com/user/unclefalter/media/tvtboards2_zpssy81hx8b.jpg.html?sort=3&o=0> &o=0

 

http://s1381.photobucket.com/user/unclefalter/media/tvtboards5_zpsuo81gg5q.jpg.html?sort=3 <http://s1381.photobucket.com/user/unclefalter/media/tvtboards5_zpsuo81gg5q.jpg.html?sort=3&o=4> &o=4

 

http://s1381.photobucket.com/user/unclefalter/media/tvtboards2_zpssy81hx8b.jpg.html?sort=3&o=0

 

The thing I found weird with them was that they didn’t have any tinning on the copper side.  SWTPC usually did that on their commercial products (they did it on the boards for my TV Typewriter II).  So I thought hrm, maybe these were done by a hobbyist?  The silkscreening included one of the corner marks found in the magazine-published artwork for the boards, which I thought would be an odd thing to include.  So either they really are SWTPC boards, or somehow someone pulled off the silkscreening, or maybe they were replicated later.
Show quoted textHide quoted text
From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] 
Sent: Wednesday, September 30, 2015 3:07 AM
To: Homebrew_PCBs@yahoogroups.com
Subject: Re: [Homebrew_PCBs] G-10 questions

 

  

On 30/09/2015 10:53, 'Dave G4UGM' dave.g4ugm@... [Homebrew_PCBs] 
wrote:
> When did etch resist pens come in? Pretty sure they were around in 1972.

I vaguely remember using a Decon Dalo pen around then (they are still 
available), but I could be wrong. I found that cellulose paint made 
easier to use by mixing it with thinners worked better, and was much 
cheaper.

Leon
-- 
Leon Heller
G1HSM



  _____  

No virus found in this message.
Checked by AVG - www.avg.com <http://www.avg.com> 
Version: 2015.0.6086 / Virus Database: 4409/10551 - Release Date: 08/31/15
Internal Virus Database is out of date.

Re: [Homebrew_PCBs] Re: G-10 questions

2015-10-01 by rolohar@...

Sweet Memories: 

There was once a really super company called Kepro. 

They sold presensitized (with Kodak KPR) boards stock, both paper and G10 epoxy, for very 
reasonable prices, and in a variety of sizes. You could even send in your own material and 
they would coat it for you. 

They also made a comprehensive array of photo-coat/expose/etch equipment, good enough 
proto and light production operations. 

When the Feds put a ban on aromatic compounds like Kodak KPR and others, the entire 
industry went belly up, including the aforementioned DynaChem, which was also pretty good 
stuff if you took the time to learn how to use it correctly. 

I think most small-timers went to dry film resist, which is still available from several offshore 
sellers on Ebay. There are also some sellers of liquid resist on Ebay. 

I just prefer to purchase presensitized material from several suppliers on Ebay, along with 
the required developer and plating solutions. 

Of course etching is a cinch using a mixture of hydrogen peroxide and muriatic acid, which 
is sold in my neck of the woods as swimming pool cleaner. 

Copy machine transfer is good if you like to fart around all day just to produce a single 
PCB. 

Keep the faith. 

Roland F. Harriston, P.D. 
************************* 
Show quoted textHide quoted text
----- Original Message -----

From: "roger@... [Homebrew_PCBs]" <Homebrew_PCBs@yahoogroups.com> 
To: "Homebrew PCBs" <Homebrew_PCBs@yahoogroups.com> 
Sent: Wednesday, September 30, 2015 8:34:54 AM 
Subject: [Homebrew_PCBs] Re: G-10 questions 



I also built boards in the early years. One of the spray on resists was produced by a company called Dynachem. It was a system that required a solvent developer and a dye to color it so you could see what was going on. Going by the odor of the product, it was probably the same product later sold through GC Electronics with the dye added to the resist. Bishop graphics made the the stick on pattters for the tape up artwork. They patterns were available in 1X, 2X and larger IIIRC. I had a camera lens I picked up at a surplus store and made my own setup for 2X artwork and used Kodalith sheet film for the negatives. The spray on resist gave me inconsistant results, probably more my fault than the products fault. There was also a dry transfer product that used rub-on patterns and traced. There were also dry transfer letters for labels on projects. I still have some of the G10 copper clad material from that era never used it all.

Re: G-10 questions

2015-10-01 by Paul Alciatore

>Paul
>Just to correct your statement
>"Then the boards were exposed to either direct sunlight or a bulb 
>that had heavy IR content in it's light."
>
>The resist is not sensitive to infra red (IR), it is sensitive to 
>ultraviolet (UV).
>
>Malcolm


Malcolm, You are quite correct. I had meant to go back and check that 
but forgot. Thanks for keeping me honest. Apologies to all for the mistake.


Paul A.

Re: [Homebrew_PCBs] G-10 questions

2015-10-05 by lists

In article <1443568483.26757.YahooMailBasic@...>,
   Malcolm Parker-Lisberg mparkerlisberg@... [Homebrew_PCBs]
<Homebrew_PCBs@yahoogroups.com> wrote:
> Copper clad FR4 was available, but a lot of SRBP was used as it was much
> cheaper. The first method was to paint, by hand, using mothers thinned
> nail varnish onto a carbon paper print traced from the layout printout.

I was using car touch-up paint. Remember those little tins with a small
paint-brush fixed inside the lid?

Then drilled by hand using a 1mm HSS bit held in a pin-holder chuck; good
job SRBP was no near as abrasive as glass fibre board is.

-- 
Stuart Winsor

Tools With A Mission
sending tools across the world
http://www.twam.co.uk/

RE: [Homebrew_PCBs] Re: G-10 questions

2015-10-06 by Brad

Thanks guys.

 

I think the important thing for me is getting as close as I can to original material/look.  If the toner process works just as well and avoids some difficulting in finding presensitized boards, I could go that route. Whatever it is, I just want something that has that vintage G10 green look.

 

Brad
Show quoted textHide quoted text
From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] 
Sent: Thursday, October 1, 2015 12:55 PM
To: Homebrew PCBs <Homebrew_PCBs@yahoogroups.com>
Subject: Re: [Homebrew_PCBs] Re: G-10 questions

 

  

Sweet Memories:

 

There was once a really super company called Kepro.

 

They sold presensitized (with Kodak KPR) boards stock, both paper and G10 epoxy, for very

reasonable prices, and in a variety of sizes. You could even send in your own material and

they would coat it for you.

 

They also made a comprehensive array of photo-coat/expose/etch equipment, good enough

proto and light production operations.

 

When the Feds put a ban on aromatic compounds like Kodak KPR and others, the entire

industry went belly up, including the aforementioned DynaChem, which was also pretty good

stuff if you took the time to learn how to use it correctly.

 

I think most small-timers went to dry film resist, which is still available from several offshore

sellers on Ebay. There are also some sellers of liquid resist on Ebay.

 

I just prefer to purchase presensitized material from several suppliers on Ebay, along with

the required developer and plating solutions.

 

Of course etching is a cinch using a mixture of hydrogen peroxide and muriatic acid, which

is sold in my neck of the woods as swimming pool cleaner.

 

Copy machine transfer is good if you like to fart around all day just to produce a single

PCB.

 

Keep the faith.

 

Roland F. Harriston, P.D.

*************************

 

  _____  

From: "roger@... [Homebrew_PCBs]" <Homebrew_PCBs@yahoogroups.com>
To: "Homebrew PCBs" <Homebrew_PCBs@yahoogroups.com>
Sent: Wednesday, September 30, 2015 8:34:54 AM
Subject: [Homebrew_PCBs] Re: G-10 questions

 

 

I also built boards in the early years. One of the spray on resists was produced by a company called Dynachem. It was a system that required a solvent developer and a dye to color it so you could see what was going on. Going by the odor of the product, it was probably the same product later sold through GC Electronics with the dye added to the resist. Bishop graphics made the the stick on pattters for the tape up artwork. They patterns were available in 1X, 2X and larger IIIRC. I had a camera lens I picked up at a surplus store and made my own setup for 2X artwork and used Kodalith sheet film for the negatives. The spray on resist gave me inconsistant results, probably more my fault than the products fault. There was also a dry transfer product that used rub-on patterns and traced. There were also dry transfer letters for labels on projects. I still have some of the G10 copper clad material from that era never used it all.

 



  _____  

No virus found in this message.
Checked by AVG - www.avg.com <http://www.avg.com> 
Version: 2015.0.6086 / Virus Database: 4409/10551 - Release Date: 08/31/15
Internal Virus Database is out of date.

RE: [Homebrew_PCBs] Re: G-10 questions

2015-10-06 by Malcolm Parker-Lisberg

You can get toner transfer sheet on ebay from China, but I use gloss photo paper meant for ink jet printers to print the laser image onto.  I then place the heat transferred paper and PCB into the freezer for 20 mins and the paper peels off leaving a perfect image on the copper for etching.

Malcolm

I don't suffer from insanity I enjoy it!
Mene, mene, tekel, upharsin
The writing is on the wall.
Ha-ktovet al ha-kir

--------------------------------------------
On Tue, 10/6/15, 'Brad' unclefalter@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
Show quoted textHide quoted text
 Subject: RE: [Homebrew_PCBs] Re: G-10 questions
 To: Homebrew_PCBs@yahoogroups.com
 Date: Tuesday, October 6, 2015, 6:58 PM
 
 
  
 
 
 
   
 
 
     
       
       
       Thanks guys.  I think the important thing for me
 is getting as close as I can to original material/look.  If
 the toner process works just as well and avoids some
 difficulting in finding presensitized boards, I could go
 that route. Whatever it is, I just want something that has
 that vintage G10 green look.  Brad  From: Homebrew_PCBs@yahoogroups.com
 [mailto:Homebrew_PCBs@yahoogroups.com] 
 Sent: Thursday, October 1, 2015 12:55
 PM
 To: Homebrew PCBs
 <Homebrew_PCBs@yahoogroups.com>
 Subject: Re: [Homebrew_PCBs] Re: G-10
 questions    Sweet
 Memories:
  There was once
 a really super company called Kepro.
  They sold
 presensitized (with Kodak KPR) boards stock, both paper and
 G10 epoxy, for veryreasonable
 prices, and in a variety of sizes. You could even send in
 your own material andthey would
 coat it for you.
  They also made
 a comprehensive array of photo-coat/expose/etch equipment,
 good enoughproto and
 light production operations.
  When the Feds
 put a ban on aromatic compounds like Kodak KPR and others,
 the entireindustry went
 belly up, including the aforementioned DynaChem, which was
 also pretty goodstuff if you
 took the time to learn how to use it
 correctly.
  I think most
 small-timers went to dry film resist, which is still
 available from several offshoresellers on
 Ebay. There are also some sellers of liquid resist on
 Ebay.
  I just prefer
 to purchase presensitized material from several suppliers on
 Ebay, along withthe required
 developer and plating solutions.
  Of course
 etching is a cinch using a mixture of hydrogen peroxide and
 muriatic acid, whichis sold in my
 neck of the woods as swimming pool
 cleaner.
  Copy machine
 transfer is good if you like to fart around all day just to
 produce a singlePCB.
  Keep the
 faith.
  Roland F.
 Harriston, P.D.*************************
  From:
 "roger@rogerandlinda.net
 [Homebrew_PCBs]"
 <Homebrew_PCBs@yahoogroups.com>
 To:
 "Homebrew PCBs"
 <Homebrew_PCBs@yahoogroups.com>
 Sent: Wednesday, September 30, 2015
 8:34:54 AM
 Subject: [Homebrew_PCBs]
 Re: G-10 questions
   I also built
 boards in the early years. One of the spray on resists was
 produced by a company called Dynachem. It was a system that
 required a solvent developer and a dye to color it so you
 could see what was going on. Going by the odor of the
 product, it was probably the same product later sold through
 GC Electronics with the dye added to the resist. Bishop
 graphics made the the stick on pattters for the tape up
 artwork. They patterns were available in 1X, 2X and larger
 IIIRC. I had a camera lens I picked up at a surplus store
 and made my own setup for 2X artwork and used Kodalith sheet
 film for the negatives. The spray on resist gave me
 inconsistant results, probably more my fault than the
 products fault. There was also a dry transfer product that
 used rub-on patterns and traced. There were also dry
 transfer letters for labels on projects. I still have some
 of the G10 copper clad material from that era never used it
 all.
  No virus found in this
 message.
 Checked by AVG - www.avg.com
 Version: 2015.0.6086 / Virus Database:
 4409/10551 - Release Date: 08/31/15
 Internal
 Virus Database is out of date. 
 
     
      
 
     
     
 
 
 
 #yiv2387718152 #yiv2387718152 --

RE: [Homebrew_PCBs] Re: G-10 questions

2015-10-06 by Brad

I tried using glossy photo paper in my laser once (by accident).. the heat caused it to melt kind of and shred itself.  Maybe the wrong printer?  I have an actual Minolta copier here too.  

 

I was down with the laser method but the fellow that made this video described a process that seemed rather simple to me: https://www.youtube.com/watch?v=42GyLYxwris

 

The trouble for me is finding boards that are the right size (I think the ‘mainboard’ has to be 6”x9”) and then trying to find one that has the right vintage look.
Show quoted textHide quoted text
From: Homebrew_PCBs@...m [mailto:Homebrew_PCBs@yahoogroups.com] 
Sent: Tuesday, October 6, 2015 11:47 AM
To: Homebrew_PCBs@yahoogroups.com
Subject: RE: [Homebrew_PCBs] Re: G-10 questions

 

  

You can get toner transfer sheet on ebay from China, but I use gloss photo paper meant for ink jet printers to print the laser image onto. I then place the heat transferred paper and PCB into the freezer for 20 mins and the paper peels off leaving a perfect image on the copper for etching.

Malcolm

I don't suffer from insanity I enjoy it!
Mene, mene, tekel, upharsin
The writing is on the wall.
Ha-ktovet al ha-kir

--------------------------------------------
On Tue, 10/6/15, 'Brad' unclefalter@yahoo.ca [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:

Subject: RE: [Homebrew_PCBs] Re: G-10 questions
To: Homebrew_PCBs@yahoogroups.com
Date: Tuesday, October 6, 2015, 6:58 PM


 









Thanks guys.  I think the important thing for me
is getting as close as I can to original material/look.  If
the toner process works just as well and avoids some
difficulting in finding presensitized boards, I could go
that route. Whatever it is, I just want something that has
that vintage G10 green look.  Brad  From: Homebrew_PCBs@yahoogroups.com
[mailto:Homebrew_PCBs@yahoogroups.com] 
Sent: Thursday, October 1, 2015 12:55
PM
To: Homebrew PCBs
<Homebrew_PCBs@...m>
Subject: Re: [Homebrew_PCBs] Re: G-10
questions    Sweet
Memories:
 There was once
a really super company called Kepro.
 They sold
presensitized (with Kodak KPR) boards stock, both paper and
G10 epoxy, for veryreasonable
prices, and in a variety of sizes. You could even send in
your own material andthey would
coat it for you.
 They also made
a comprehensive array of photo-coat/expose/etch equipment,
good enoughproto and
light production operations.
 When the Feds
put a ban on aromatic compounds like Kodak KPR and others,
the entireindustry went
belly up, including the aforementioned DynaChem, which was
also pretty goodstuff if you
took the time to learn how to use it
correctly.
 I think most
small-timers went to dry film resist, which is still
available from several offshoresellers on
Ebay. There are also some sellers of liquid resist on
Ebay.
 I just prefer
to purchase presensitized material from several suppliers on
Ebay, along withthe required
developer and plating solutions.
 Of course
etching is a cinch using a mixture of hydrogen peroxide and
muriatic acid, whichis sold in my
neck of the woods as swimming pool
cleaner.
 Copy machine
transfer is good if you like to fart around all day just to
produce a singlePCB.
 Keep the
faith.
 Roland F.
Harriston, P.D.*************************
 From:
"roger@...
[Homebrew_PCBs]"
<Homebrew_PCBs@yahoogroups.com>
To:
"Homebrew PCBs"
<Homebrew_PCBs@yahoogroups.com>
Sent: Wednesday, September 30, 2015
8:34:54 AM
Subject: [Homebrew_PCBs]
Re: G-10 questions
  I also built
boards in the early years. One of the spray on resists was
produced by a company called Dynachem. It was a system that
required a solvent developer and a dye to color it so you
could see what was going on. Going by the odor of the
product, it was probably the same product later sold through
GC Electronics with the dye added to the resist. Bishop
graphics made the the stick on pattters for the tape up
artwork. They patterns were available in 1X, 2X and larger
IIIRC. I had a camera lens I picked up at a surplus store
and made my own setup for 2X artwork and used Kodalith sheet
film for the negatives. The spray on resist gave me
inconsistant results, probably more my fault than the
products fault. There was also a dry transfer product that
used rub-on patterns and traced. There were also dry
transfer letters for labels on projects. I still have some
of the G10 copper clad material from that era never used it
all.
 No virus found in this
message.
Checked by AVG - www.avg.com
Version: 2015.0.6086 / Virus Database:
4409/10551 - Release Date: 08/31/15
Internal
Virus Database is out of date. 









#yiv2387718152 #yiv2387718152 --

RE: [Homebrew_PCBs] Re: G-10 questions

2015-10-07 by Tony Smith

Wrong paper, the stuff you had was for an inkjet printer.

 

You need to check if the paper is for laser.  I don’t know what the different coatings are but generally one won’t work in the other.  Or if it does the results are poor.

 

Some people are using actual lasers to do PCBs.  One method is to use an UV laser to expose a sensitised board.  Probably not worth the effort as it’s rather slow (with lasers people like us can afford anyway) since you’re raster etching, and depending on your mechanicals will be less accurate than using a mask & UV lamps.

 

UV laser: https://www.youtube.com/watch?v=4SNkzoOvoD8, end result look good.

 

I own a few CO2 lasers (the ones you get on eBay) so the other method is of interest to me.  You take a plain copper board, paint it, and burn off the paint.  Etch the exposed copper and you’re done.

 

https://youtu.be/8j8PSk57xWU?t=4m10s. (I’ve got that same machine).  A bit of slow video, jump to 7:30 for the etching.

 

Once etched you could put it back in the laser to do the holes.  Double-sided would require drilling registration pins or something.

 

He’s raster etching as well (slow!) but you could do isolation milling.  Diptrace exports that as standard – nice!  As an isolation that board would only take a couple of minutes, and certainly quieter than a mill.

 

https://www.youtube.com/watch?v=EBUsOGMQdhM show the speed difference.  (Gah music and half the video seems to be missing but anyway.)

 

Hardest part seems to be finding a good paint (burns cleanly, no residue, resists etch), but everything from flat black to clear top coat seems to more-or-less work.

 

The ultimate is this: https://youtu.be/r2Vx_ErDiQM?t=0m55s.  You can do the holes as well.  Amazing considering some systems use copper as the mirrors!

 

Tony
Show quoted textHide quoted text
From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] 
Sent: Wednesday, 7 October 2015 8:32 AM
To: Homebrew_PCBs@yahoogroups.com
Subject: RE: [Homebrew_PCBs] Re: G-10 questions

 

I tried using glossy photo paper in my laser once (by accident).. the heat caused it to melt kind of and shred itself.  Maybe the wrong printer?  I have an actual Minolta copier here too.  

 

I was down with the laser method but the fellow that made this video described a process that seemed rather simple to me: https://www.youtube.com/watch?v=42GyLYxwris

 

The trouble for me is finding boards that are the right size (I think the ‘mainboard’ has to be 6”x9”) and then trying to find one that has the right vintage look.

 

From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] 
Sent: Tuesday, October 6, 2015 11:47 AM
To: Homebrew_PCBs@yahoogroups.com
Subject: RE: [Homebrew_PCBs] Re: G-10 questions

 

  

You can get toner transfer sheet on ebay from China, but I use gloss photo paper meant for ink jet printers to print the laser image onto. I then place the heat transferred paper and PCB into the freezer for 20 mins and the paper peels off leaving a perfect image on the copper for etching.

Malcolm

I don't suffer from insanity I enjoy it!
Mene, mene, tekel, upharsin
The writing is on the wall.
Ha-ktovet al ha-kir

--------------------------------------------
On Tue, 10/6/15, 'Brad' unclefalter@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:

Subject: RE: [Homebrew_PCBs] Re: G-10 questions
To: Homebrew_PCBs@yahoogroups.com
Date: Tuesday, October 6, 2015, 6:58 PM


 









Thanks guys.  I think the important thing for me
is getting as close as I can to original material/look.  If
the toner process works just as well and avoids some
difficulting in finding presensitized boards, I could go
that route. Whatever it is, I just want something that has
that vintage G10 green look.  Brad  From: Homebrew_PCBs@yahoogroups.com
[mailto:Homebrew_PCBs@yahoogroups.com] 
Sent: Thursday, October 1, 2015 12:55
PM
To: Homebrew PCBs
<Homebrew_PCBs@yahoogroups.com>
Subject: Re: [Homebrew_PCBs] Re: G-10
questions    Sweet
Memories:
 There was once
a really super company called Kepro.
 They sold
presensitized (with Kodak KPR) boards stock, both paper and
G10 epoxy, for veryreasonable
prices, and in a variety of sizes. You could even send in
your own material andthey would
coat it for you.
 They also made
a comprehensive array of photo-coat/expose/etch equipment,
good enoughproto and
light production operations.
 When the Feds
put a ban on aromatic compounds like Kodak KPR and others,
the entireindustry went
belly up, including the aforementioned DynaChem, which was
also pretty goodstuff if you
took the time to learn how to use it
correctly.
 I think most
small-timers went to dry film resist, which is still
available from several offshoresellers on
Ebay. There are also some sellers of liquid resist on
Ebay.
 I just prefer
to purchase presensitized material from several suppliers on
Ebay, along withthe required
developer and plating solutions.
 Of course
etching is a cinch using a mixture of hydrogen peroxide and
muriatic acid, whichis sold in my
neck of the woods as swimming pool
cleaner.
 Copy machine
transfer is good if you like to fart around all day just to
produce a singlePCB.
 Keep the
faith.
 Roland F.
Harriston, P.D.*************************
 From:
"roger@...
[Homebrew_PCBs]"
<Homebrew_PCBs@yahoogroups.com>
To:
"Homebrew PCBs"
<Homebrew_PCBs@yahoogroups.com>
Sent: Wednesday, September 30, 2015
8:34:54 AM
Subject: [Homebrew_PCBs]
Re: G-10 questions
  I also built
boards in the early years. One of the spray on resists was
produced by a company called Dynachem. It was a system that
required a solvent developer and a dye to color it so you
could see what was going on. Going by the odor of the
product, it was probably the same product later sold through
GC Electronics with the dye added to the resist. Bishop
graphics made the the stick on pattters for the tape up
artwork. They patterns were available in 1X, 2X and larger
IIIRC. I had a camera lens I picked up at a surplus store
and made my own setup for 2X artwork and used Kodalith sheet
film for the negatives. The spray on resist gave me
inconsistant results, probably more my fault than the
products fault. There was also a dry transfer product that
used rub-on patterns and traced. There were also dry
transfer letters for labels on projects. I still have some
of the G10 copper clad material from that era never used it
all.
 No virus found in this
message.
Checked by AVG - www.avg.com
Version: 2015.0.6086 / Virus Database:
4409/10551 - Release Date: 08/31/15
Internal
Virus Database is out of date. 









#yiv2387718152 #yiv2387718152 --

Re: G-10 questions

2015-12-28 by me@...

I tape a piece of wax paper to a regular piece of paper then print on that with the LaserJet. Works great. Since the wax paper is translucent, it really aids in lining up the transfer on the copper.

RE: [Homebrew_PCBs] Re: G-10 questions

2015-12-28 by Enzo Fiorillo

Thanks. I´ll tryEnzo


From: Homebrew_PCBs@yahoogroups.com
To: Homebrew_PCBs@yahoogroups.com
Date: Mon, 28 Dec 2015 09:47:38 -0800
Subject: [Homebrew_PCBs] Re: G-10 questions














































      I tape a piece of wax paper to a regular piece of paper then print on that with the LaserJet.  Works great.   Since the wax paper is translucent, it really aids in lining up the transfer on the copper.

Re: [Homebrew_PCBs] Re: G-10 questions

2015-12-28 by Donald H Locker

Waxed paper or baking parchment? I would expect the former's coating to melt in the printer and make a mess of it; the parchment should survive OK.

Donald.

----- Original Message -----
Show quoted textHide quoted text
> From: "me@... [Homebrew_PCBs]" <Homebrew_PCBs@yahoogroups.com>
> To: "Homebrew PCBs" <Homebrew_PCBs@yahoogroups.com>
> Sent: Monday, December 28, 2015 12:47:38 PM
> Subject: [Homebrew_PCBs] Re: G-10 questions
> 
> I tape a piece of wax paper to a regular piece of paper then print on that
> with the LaserJet.  Works great.   Since the wax paper is translucent, it
> really aids in lining up the transfer on the copper.

Re: [Homebrew_PCBs] Re: G-10 questions

2015-12-31 by me@...

Wax paper works fine. I have been using it for months with no noticeable issues. I use Reynolds wax paper. Other off brand wax paper yieds poor results.

RE: [Homebrew_PCBs] Re: G-10 questions

2015-12-31 by keith printy

I was thinking about this and knowing how the fuser is constructed in the laser jet the wax would only get on the Teflon sleeve . since it would provide additional lubrication I would see no issues from that. The other parts of the printer are not at high temperature so would not be an issue. If it did muck up the fuser the sleeve is replaceable if you do disassembly of the fuser or you likely could just clean it.





From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com]
Sent: Thursday, December 31, 2015 11:20 AM
To: Homebrew_PCBs@yahoogroups.com
Subject: Re: [Homebrew_PCBs] Re: G-10 questions








Wax paper works fine.     I have been using it for months with no noticeable issues.   I use Reynolds wax paper.   Other off brand wax paper yieds poor results.

Re: [Homebrew_PCBs] Re: G-10 questions

2016-01-03 by Donald H Locker

Thank you.

----- Original Message -----
Show quoted textHide quoted text
> From: "me@... [Homebrew_PCBs]" <Homebrew_PCBs@yahoogroups.com>
> To: "Homebrew PCBs" <Homebrew_PCBs@yahoogroups.com>
> Sent: Thursday, December 31, 2015 11:20:01 AM
> Subject: Re: [Homebrew_PCBs] Re: G-10 questions
> 
> Wax paper works fine.     I have been using it for months with no noticeable
> issues.   I use Reynolds wax paper.   Other off brand wax paper yieds poor
> results.

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