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Good techniques for cleaning up old artwork?

Good techniques for cleaning up old artwork?

2017-02-16 by Brad

My TV Typewriter project is getting close to the finish line so I’m working on lining up a new project.

 

What I’d like to do next is a replica of the SOL terminal prototype that appeared in Popular Electronics in July of 1976.  I have the artwork for it here:

 

http://www.sol20.org/articles/img/PE_SOL.pdf

 

As you can see, the quality of the scan is pretty lousy.  There’s no other sources for this that I’ve found.  I can clean it up manually with Photoshop or Illustrator (and in fact have started on the former) but that will take hours (months, probably).  I’m wondering if there’s a better technique than endlessly using the rectangle tool to remake the traces and remote the ‘noise’.

 

I expect there will be other challenges, being that this is a double sided board.  There *isn’t* a way for a home PCB maker to do thru-plate without third party help is there?  I don’t want to send this off to a board house because of the likely cost but also because that’s not how a hobbyist would have done it back then.  Since this artwork was sent to those that wrote in for it, I’m assuming they just created it as a two sided board the usual way and then soldered in the connections between sides via ICs, jumper wire, etc.

 

I also don’t want to completely redraw the thing.  For me, that would lose the spiritual connection to the original artwork.  I’m trying to leave as much of it as original as possible.

 

Anyway, thoughts and suggestions here are most welcome.

 

Re: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

2017-02-16 by Harvey Altstadter

Brad,

I looked at your artwork scans. WOW. Has anyone suggested that you might be a glutton for punishment?

I noticed that the first two scans are much cleaner than the others. If you have access to the pages that they were scanned from, you should re-scan with the lines square to the scanning direction. This will produce much cleaner results.

Before you invest too much time is trying to make clean artwork using the scans as a basis, make sure that the scanning process didn't distort the dimensions in one direction or the other. I have found small differences in the scaling between the x and y axes that make assembly of 40 pin ICs, or long connectors impossible.

These boards will be difficult to etch. The combination of large open spaces and very narrow traces may make it difficult to keep the traces from over etching.

To answer your question about plated through holes, they can be done, but it is a bit involved. There are a number of tutorials on making plated through holes on YouTube. Here are two of them:

Process 1:

https://www.youtube.com/watch?v=KTNuTv_IQp4

Process 2:

https://www.youtube.com/watch?v=s3GY-j4Gh0E

https://www.youtube.com/watch?v=9rME-XGCcCo

I have not tried either of these processes, but they do seem possible.  The difficulty I see with your boards is the sheer number of holes. The possibility that one or more of the holes, especially the small via holes, not getting plated through is very great. Finding an open would be very difficult, not to mention time consuming.

One thing to remember: The holes are drilled and plated before the board is etched. This means that the holes need to be protected during the etching process. It seems to me that the best process for doing this would be the photoresist process. The photomask used for resist exposure would need to have the drill holes omitted, so the resist will tent over the holes during etching. Drilling before photomasking has the benefit that it makes the mask easier to align. I would suggest that some extra pads with holes should be included on the masks to assist with alignment. These pads would include the drill holes. This also improves the probability that two sided boards would have proper alignment between sides.

Harvey
On 2/15/2017 6:04 PM, 'Brad' unclefalter@... [Homebrew_PCBs] wrote:
 

My TV Typewriter project is getting close to the finish line so I’m working on lining up a new project.

 

What I’d like to do next is a replica of the SOL terminal prototype that appeared in Popular Electronics in July of 1976.  I have the artwork for it here:

 

http://www.sol20.org/articles/img/PE_SOL.pdf

 

As you can see, the quality of the scan is pretty lousy.  There’s no other sources for this that I’ve found.  I can clean it up manually with Photoshop or Illustrator (and in fact have started on the former) but that will take hours (months, probably).  I’m wondering if there’s a better technique than endlessly using the rectangle tool to remake the traces and remote the ‘noise’.

 

I expect there will be other challenges, being that this is a double sided board.  There *isn’t* a way for a home PCB maker to do thru-plate without third party help is there?  I don’t want to send this off to a board house because of the likely cost but also because that’s not how a hobbyist would have done it back then.  Since this artwork was sent to those that wrote in for it, I’m assuming they just created it as a two sided board the usual way and then soldered in the connections between sides via ICs, jumper wire, etc.

 

I also don’t want to completely redraw the thing.  For me, that would lose the spiritual connection to the original artwork.  I’m trying to leave as much of it as original as possible.

 

Anyway, thoughts and suggestions here are most welcome.

 


RE: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

2017-02-16 by Brad

Thanks so much for all this!

 

Yes, I think this will be a very difficult project.  But I like challenges, even if I fail. 

 

Unfortunately as far as I know there are no better copies of the artwork.  The mail-in offer for these plans was out only briefly in 1976 and so far only one person has come forward with originals, which is what these scans were based on.  Cleaning up the artwork will take a long time but I don’t think it’s impossible – I’d just hoped for some faster method.

 

Recently I acquired an original set of plans for the 1974 Mark-8 mini-computer.  I have original boards and now these, but had originally planned in the absence of both to make clone boards from scanned copies of the plans online.  I was stunned to realize just how badly off the scans were when I compared the three.

 

Likewise on my TV Typewriter.  Although I had the foresight to print every pattern after scaling and check each individual IC, I neglected to consider the bus connectors that stack the four TVT boards together vertically.  I’ve made it work but it’s an awkward squeeze, because one of those connectors is skewed slightly to the left.  I have printed off several random sections of this artwork after scaling it correctly and so far tihngs fit perfectly.  I don’t have to worry about connecting other boards, so I can use the techniques I’ve learned to get top and bottom perfectly aligned.  But yeah, the through plate situation is tricky.

 

I mean, I could just adopt the approach used by Mark-8 builders – even the original boards, although double-sided, were not through plate. You had to solder on both sides.  I could do that, although the original board in this case had IC sockets.  Not sure how you’d solder both sides of a socket.

 

One other thing I’m thinking about now.. this board is much larger than 8x11 – I’m guessing my only option re: toner transfer is to use two blue press n peel sheets per side?

 

Thanks for all your help and information!  It is greatly appreciated.

 

 

From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com]
Sent: Wednesday, February 15, 2017 9:24 PM
To: Homebrew_PCBs@yahoogroups.com
Subject: Re: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

 

 

Brad,

I looked at your artwork scans. WOW. Has anyone suggested that you might be a glutton for punishment?

I noticed that the first two scans are much cleaner than the others. If you have access to the pages that they were scanned from, you should re-scan with the lines square to the scanning direction. This will produce much cleaner results.

Before you invest too much time is trying to make clean artwork using the scans as a basis, make sure that the scanning process didn't distort the dimensions in one direction or the other. I have found small differences in the scaling between the x and y axes that make assembly of 40 pin ICs, or long connectors impossible.

These boards will be difficult to etch. The combination of large open spaces and very narrow traces may make it difficult to keep the traces from over etching.

To answer your question about plated through holes, they can be done, but it is a bit involved. There are a number of tutorials on making plated through holes on YouTube. Here are two of them:

Process 1:

https://www.youtube.com/watch?v=KTNuTv_IQp4

Process 2:

https://www.youtube.com/watch?v=s3GY-j4Gh0E

https://www.youtube.com/watch?v=9rME-XGCcCo

I have not tried either of these processes, but they do seem possible.� The difficulty I see with your boards is the sheer number of holes. The possibility that one or more of the holes, especially the small via holes, not getting plated through is very great. Finding an open would be very difficult, not to mention time consuming.

One thing to remember: The holes are drilled and plated before the board is etched. This means that the holes need to be protected during the etching process. It seems to me that the best process for doing this would be the photoresist process. The photomask used for resist exposure would need to have the drill holes omitted, so the resist will tent over the holes during etching. Drilling before photomasking has the benefit that it makes the mask easier to align. I would suggest that some extra pads with holes should be included on the masks to assist with alignment. These pads would include the drill holes. This also improves the probability that two sided boards would have proper alignment between sides.

Harvey

On 2/15/2017 6:04 PM, 'Brad' unclefalter@... [Homebrew_PCBs] wrote:

�

My TV Typewriter project is getting close to the finish line so I�m working on lining up a new project.

�

What I�d like to do next is a replica of the SOL terminal prototype that appeared in Popular Electronics in July of 1976.� I have the artwork for it here:

�

http://www.sol20.org/articles/img/PE_SOL.pdf

�

As you can see, the quality of the scan is pretty lousy.� There�s no other sources for this that I�ve found.� I can clean it up manually with Photoshop or Illustrator (and in fact have started on the former) but that will take hours (months, probably).� I�m wondering if there�s a better technique than endlessly using the rectangle tool to remake the traces and remote the �noise�.

�

I expect there will be other challenges, being that this is a double sided board.� There *isn�t* a way for a home PCB maker to do thru-plate without third party help is there?� I don�t want to send this off to a board house because of the likely cost but also because that�s not how a hobbyist would have done it back then.� Since this artwork was sent to those that wrote in for it, I�m assuming they just created it as a two sided board the usual way and then soldered in the connections between sides via ICs, jumper wire, etc.

�

I also don�t want to completely redraw the thing.� For me, that would lose the spiritual connection to the original artwork.� I�m trying to leave as much of it as original as possible.

�

Anyway, thoughts and suggestions here are most welcome.

�

 

RE: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

2017-02-16 by Malcolm Parker-Lisberg

For homemade double sided non-plated through I use fine tinned copper wire, through the board and bent over on the top and soldered to the top pad. Then use IC sockets with tape pins, not round, and you can then insert the socket, if you have position the wire correctly, and then solder wire and pin to the bottom pad.

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 Thu, 2/16/17, 'Brad' unclefalter@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:

Subject: RE: [Homebrew_PCBs] Good techniques for cleaning up old artwork?
To: Homebrew_PCBs@yahoogroups.com
Date: Thursday, February 16, 2017, 4:42 PM


 









Thanks so much for all
this!  Yes, I think this will be a very
difficult project.  But I like challenges, even if I
fail.   Unfortunately as far as I know
there are no better copies of the artwork.  The mail-in
offer for these plans was out only briefly in 1976 and so
far only one person has come forward with originals, which
is what these scans were based on.  Cleaning up the artwork
will take a long time but I don’t think it’s impossible
– I’d just hoped for some faster method.  Recently I acquired an original
set of plans for the 1974 Mark-8 mini-computer.  I have
original boards and now these, but had originally planned in
the absence of both to make clone boards from scanned copies
of the plans online.  I was stunned to realize just how
badly off the scans were when I compared the
three.  Likewise on my TV Typewriter. 
Although I had the foresight to print every pattern after
scaling and check each individual IC, I neglected to
consider the bus connectors that stack the four TVT boards
together vertically.  I’ve made it work but it’s an
awkward squeeze, because one of those connectors is skewed
slightly to the left.  I have printed off several random
sections of this artwork after scaling it correctly and so
far tihngs fit perfectly.  I don’t have to worry about
connecting other boards, so I can use the techniques I’ve
learned to get top and bottom perfectly aligned.  But yeah,
the through plate situation is tricky.  I mean, I could just adopt the
approach used by Mark-8 builders – even the original
boards, although double-sided, were not through plate. You
had to solder on both sides.  I could do that, although the
original board in this case had IC sockets.  Not sure how
you’d solder both sides of a socket.  One other thing I’m thinking
about now.. this board is much larger than 8x11 – I’m
guessing my only option re: toner transfer is to use two
blue press n peel sheets per side?  Thanks for all your help and
information!  It is greatly appreciated.    From: Homebrew_PCBs@yahoogroups.com
[mailto:Homebrew_PCBs@yahoogroups.com]
Sent: Wednesday, February 15, 2017 9:24
PM
To:
Homebrew_PCBs@yahoogroups.com
Subject: Re: [Homebrew_PCBs] Good
techniques for cleaning up old
artwork?    Brad,I looked at your
artwork scans. WOW. Has anyone suggested that you might be a
glutton for punishment? I noticed that the first two
scans are much cleaner than the others. If you have access
to the pages that they were scanned from, you should re-scan
with the lines square to the scanning direction. This will
produce much cleaner results. Before you invest too
much time is trying to make clean artwork using the scans as
a basis, make sure that the scanning process didn't
distort the dimensions in one direction or the other. I have
found small differences in the scaling between the x and y
axes that make assembly of 40 pin ICs, or long connectors
impossible. These boards will be difficult to etch.
The combination of large open spaces and very narrow traces
may make it difficult to keep the traces from over etching.
To answer your question about plated through holes,
they can be done, but it is a bit involved. There are a
number of tutorials on making plated through holes on
YouTube. Here are two of them:Process 1: https://www.youtube.com/watch?v=KTNuTv_IQp4Process
2:https://www.youtube.com/watch?v=s3GY-j4Gh0Ehttps://www.youtube.com/watch?v=9rME-XGCcCoI
have not tried either of these processes, but they do seem
possible.� The difficulty I see with your boards is the
sheer number of holes. The possibility that one or more of
the holes, especially the small via holes, not getting
plated through is very great. Finding an open would be very
difficult, not to mention time consuming.One thing to
remember: The holes are drilled and plated before the board
is etched. This means that the holes need to be protected
during the etching process. It seems to me that the best
process for doing this would be the photoresist process. The
photomask used for resist exposure would need to have the
drill holes omitted, so the resist will tent over the holes
during etching. Drilling before photomasking has the benefit
that it makes the mask easier to align. I would suggest that
some extra pads with holes should be included on the masks
to assist with alignment. These pads would include the drill
holes. This also improves the probability that two sided
boards would have proper alignment between sides.HarveyOn 2/15/2017 6:04 PM,
'Brad' unclefalter@...
[Homebrew_PCBs] wrote:� My TV Typewriter project is
getting close to the finish line so I�m working on
lining up a new project.�What I�d like to do next
is a replica of the SOL terminal prototype that appeared in
Popular Electronics in July of 1976.� I have the
artwork for it here:�http://www.sol20.org/articles/img/PE_SOL.pdf%c3%af%c2%bf%c2%bdAs you can see, the quality
of the scan is pretty lousy.� There�s no other
sources for this that I�ve found.� I can clean it
up manually with Photoshop or Illustrator (and in fact have
started on the former) but that will take hours (months,
probably).� I�m wondering if there�s a better
technique than endlessly using the rectangle tool to remake
the traces and remote the �noise�.�I expect there will be other
challenges, being that this is a double sided board.�
There *isn�t* a way for a home PCB maker to do
thru-plate without third party help is there?� I
don�t want to send this off to a board house because of
the likely cost but also because that�s not how a
hobbyist would have done it back then.� Since this
artwork was sent to those that wrote in for it, I�m
assuming they just created it as a two sided board the usual
way and then soldered in the connections between sides via
ICs, jumper wire, etc.�I also don�t want to
completely redraw the thing.� For me, that would lose
the spiritual connection to the original artwork.�
I�m trying to leave as much of it as original as
possible.�Anyway, thoughts and
suggestions here are most welcome.�  









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RE: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

2017-02-16 by Tony Smith

You can get rivets for making vias: https://www.megauk.com/through_hole_rivets.php, but ah, a bit spendy.

 

The other option is you cut short lengths of copper wire, poke them in the holes and dome them over, repeat on the other side:  https://paulwanamaker.wordpress.com/300-2/

 

The old way of making rivets (for watch chains) is to drill a shallow hole in a plate, put the wire in and form the rivet head.  Put it in the PCB and finish it off.

 

Of course there aren’t though hole, note that DIY page mentions drilling a hole thru the river with the classic “I haven’t tried it but it should work…”.  What could go wrong, eh?

 

Tony

 

 

From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com]
Sent: Friday, 17 February 2017 3:42 AM
To: Homebrew_PCBs@yahoogroups.com
Subject: RE: [Homebrew_PCBs] Good techniques for cleaning up old artwork?



Thanks so much for all this!

 

Yes, I think this will be a very difficult project.  But I like challenges, even if I fail. 

 

Unfortunately as far as I know there are no better copies of the artwork.  The mail-in offer for these plans was out only briefly in 1976 and so far only one person has come forward with originals, which is what these scans were based on.  Cleaning up the artwork will take a long time but I don’t think it’s impossible – I’d just hoped for some faster method.

 

Recently I acquired an original set of plans for the 1974 Mark-8 mini-computer.  I have original boards and now these, but had originally planned in the absence of both to make clone boards from scanned copies of the plans online.  I was stunned to realize just how badly off the scans were when I compared the three.

 

Likewise on my TV Typewriter.  Although I had the foresight to print every pattern after scaling and check each individual IC, I neglected to consider the bus connectors that stack the four TVT boards together vertically.  I’ve made it work but it’s an awkward squeeze, because one of those connectors is skewed slightly to the left.  I have printed off several random sections of this artwork after scaling it correctly and so far tihngs fit perfectly.  I don’t have to worry about connecting other boards, so I can use the techniques I’ve learned to get top and bottom perfectly aligned.  But yeah, the through plate situation is tricky.

 

I mean, I could just adopt the approach used by Mark-8 builders – even the original boards, although double-sided, were not through plate. You had to solder on both sides.  I could do that, although the original board in this case had IC sockets.  Not sure how you’d solder both sides of a socket.

 

One other thing I’m thinking about now.. this board is much larger than 8x11 – I’m guessing my only option re: toner transfer is to use two blue press n peel sheets per side?

 

Thanks for all your help and information!  It is greatly appreciated.

 

 

From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com]
Sent: Wednesday, February 15, 2017 9:24 PM
To: Homebrew_PCBs@yahoogroups.com
Subject: Re: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

 

 

Brad,

I looked at your artwork scans. WOW. Has anyone suggested that you might be a glutton for punishment?

I noticed that the first two scans are much cleaner than the others. If you have access to the pages that they were scanned from, you should re-scan with the lines square to the scanning direction. This will produce much cleaner results.

Before you invest too much time is trying to make clean artwork using the scans as a basis, make sure that the scanning process didn't distort the dimensions in one direction or the other. I have found small differences in the scaling between the x and y axes that make assembly of 40 pin ICs, or long connectors impossible.

These boards will be difficult to etch. The combination of large open spaces and very narrow traces may make it difficult to keep the traces from over etching.

To answer your question about plated through holes, they can be done, but it is a bit involved. There are a number of tutorials on making plated through holes on YouTube. Here are two of them:

Process 1:

https://www.youtube.com/watch?v=KTNuTv_IQp4

Process 2:

https://www.youtube.com/watch?v=s3GY-j4Gh0E

https://www.youtube.com/watch?v=9rME-XGCcCo

I have not tried either of these processes, but they do seem possible.� The difficulty I see with your boards is the sheer number of holes. The possibility that one or more of the holes, especially the small via holes, not getting plated through is very great. Finding an open would be very difficult, not to mention time consuming.

One thing to remember: The holes are drilled and plated before the board is etched. This means that the holes need to be protected during the etching process. It seems to me that the best process for doing this would be the photoresist process. The photomask used for resist exposure would need to have the drill holes omitted, so the resist will tent over the holes during etching. Drilling before photomasking has the benefit that it makes the mask easier to align. I would suggest that some extra pads with holes should be included on the masks to assist with alignment. These pads would include the drill holes. This also improves the probability that two sided boards would have proper alignment between sides.

Harvey

On 2/15/2017 6:04 PM, 'Brad' unclefalter@... [Homebrew_PCBs] wrote:

�

My TV Typewriter project is getting close to the finish line so I�m working on lining up a new project.

�

What I�d like to do next is a replica of the SOL terminal prototype that appeared in Popular Electronics in July of 1976.� I have the artwork for it here:

�

http://www.sol20.org/articles/img/PE_SOL.pdf

�

As you can see, the quality of the scan is pretty lousy.� There�s no other sources for this that I�ve found.� I can clean it up manually with Photoshop or Illustrator (and in fact have started on the former) but that will take hours (months, probably).� I�m wondering if there�s a better technique than endlessly using the rectangle tool to remake the traces and remote the �noise�.

�

I expect there will be other challenges, being that this is a double sided board.� There *isn�t* a way for a home PCB maker to do thru-plate without third party help is there?� I don�t want to send this off to a board house because of the likely cost but also because that�s not how a hobbyist would have done it back then.� Since this artwork was sent to those that wrote in for it, I�m assuming they just created it as a two sided board the usual way and then soldered in the connections between sides via ICs, jumper wire, etc.

�

I also don�t want to completely redraw the thing.� For me, that would lose the spiritual connection to the original artwork.� I�m trying to leave as much of it as original as possible.

�

Anyway, thoughts and suggestions here are most welcome.

�

 

 




Re: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

2017-02-16 by Will Kimber

I don't know if the Bishop Graphic sick-on tapes and pads are still available.  If so would it be practical to take your scans put some tracing paper on top then build up the image on the tracing paper with the stick-on tapes and pads. 

Would be time consuming but give accurate multi pin parts.


Cheers,

Will


On 02/17/2017 05:42 AM, 'Brad' unclefalter@... [Homebrew_PCBs] wrote:
 

Thanks so much for all this!

 

Yes, I think this will be a very difficult project.  But I like challenges, even if I fail. 

 

Unfortunately as far as I know there are no better copies of the artwork.  The mail-in offer for these plans was out only briefly in 1976 and so far only one person has come forward with originals, which is what these scans were based on.  Cleaning up the artwork will take a long time but I don’t think it’s impossible – I’d just hoped for some faster method.

 

Recently I acquired an original set of plans for the 1974 Mark-8 mini-computer.  I have original boards and now these, but had originally planned in the absence of both to make clone boards from scanned copies of the plans online.  I was stunned to realize just how badly off the scans were when I compared the three.

 

Likewise on my TV Typewriter.  Although I had the foresight to print every pattern after scaling and check each individual IC, I neglected to consider the bus connectors that stack the four TVT boards together vertically.  I’ve made it work but it’s an awkward squeeze, because one of those connectors is skewed slightly to the left.  I have printed off several random sections of this artwork after scaling it correctly and so far tihngs fit perfectly.  I don’t have to worry about connecting other boards, so I can use the techniques I’ve learned to get top and bottom perfectly aligned.  But yeah, the through plate situation is tricky.

 

I mean, I could just adopt the approach used by Mark-8 builders – even the original boards, although double-sided, were not through plate. You had to solder on both sides.  I could do that, although the original board in this case had IC sockets.  Not sure how you’d solder both sides of a socket.

 

One other thing I’m thinking about now.. this board is much larger than 8x11 – I’m guessing my only option re: toner transfer is to use two blue press n peel sheets per side?

 

Thanks for all your help and information!  It is greatly appreciated.

 

 

From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com]
Sent: Wednesday, February 15, 2017 9:24 PM
To: Homebrew_PCBs@yahoogroups.com
Subject: Re: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

 

 

Brad,

I looked at your artwork scans. WOW. Has anyone suggested that you might be a glutton for punishment?

I noticed that the first two scans are much cleaner than the others. If you have access to the pages that they were scanned from, you should re-scan with the lines square to the scanning direction. This will produce much cleaner results.

Before you invest too much time is trying to make clean artwork using the scans as a basis, make sure that the scanning process didn't distort the dimensions in one direction or the other. I have found small differences in the scaling between the x and y axes that make assembly of 40 pin ICs, or long connectors impossible.

These boards will be difficult to etch. The combination of large open spaces and very narrow traces may make it difficult to keep the traces from over etching.

To answer your question about plated through holes, they can be done, but it is a bit involved. There are a number of tutorials on making plated through holes on YouTube. Here are two of them:

Process 1:

https://www.youtube.com/watch?v=KTNuTv_IQp4

Process 2:

https://www.youtube.com/watch?v=s3GY-j4Gh0E

https://www.youtube.com/watch?v=9rME-XGCcCo

I have not tried either of these processes, but they do seem possible.� The difficulty I see with your boards is the sheer number of holes. The possibility that one or more of the holes, especially the small via holes, not getting plated through is very great. Finding an open would be very difficult, not to mention time consuming.

One thing to remember: The holes are drilled and plated before the board is etched. This means that the holes need to be protected during the etching process. It seems to me that the best process for doing this would be the photoresist process. The photomask used for resist exposure would need to have the drill holes omitted, so the resist will tent over the holes during etching. Drilling before photomasking has the benefit that it makes the mask easier to align. I would suggest that some extra pads with holes should be included on the masks to assist with alignment. These pads would include the drill holes. This also improves the probability that two sided boards would have proper alignment between sides.

Harvey

On 2/15/2017 6:04 PM, 'Brad' unclefalter@... [Homebrew_PCBs] wrote:

�

My TV Typewriter project is getting close to the finish line so I�m working on lining up a new project.

�

What I�d like to do next is a replica of the SOL terminal prototype that appeared in Popular Electronics in July of 1976.� I have the artwork for it here:

�

http://www.sol20.org/articles/img/PE_SOL.pdf

�

As you can see, the quality of the scan is pretty lousy.� There�s no other sources for this that I�ve found.� I can clean it up manually with Photoshop or Illustrator (and in fact have started on the former) but that will take hours (months, probably).� I�m wondering if there�s a better technique than endlessly using the rectangle tool to remake the traces and remote the �noise�.

�

I expect there will be other challenges, being that this is a double sided board.� There *isn�t* a way for a home PCB maker to do thru-plate without third party help is there?� I don�t want to send this off to a board house because of the likely cost but also because that�s not how a hobbyist would have done it back then.� Since this artwork was sent to those that wrote in for it, I�m assuming they just created it as a two sided board the usual way and then soldered in the connections between sides via ICs, jumper wire, etc.

�

I also don�t want to completely redraw the thing.� For me, that would lose the spiritual connection to the original artwork.� I�m trying to leave as much of it as original as possible.

�

Anyway, thoughts and suggestions here are most welcome.

�

 


RE: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

2017-02-17 by roylowenthal@...

It used to be possible to get IC sockets that were solderable from both sides. The socket pins came up over the side of the socket, making it (relatively) easy to reach them with a small iron. It's still possible to find sockets that have long enough pins to be solderable from both sides if they're not mounted flush with the board.

Roy

Re: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

2017-02-17 by Jim Pruitt

Wire Wrap sockets will allow you go get about as far above the board as you want and solder the pins on top as well.  I am not sure you can find some of the newer size sockets like the 24 and 28 pin .3inch spacing between rows types or even the 18 and 20 pin but they probably exist.

In the 70's I bought some strips of ic pins.  You broke off the number you needed per row and stuck them in the holes and soldered them (top and bottom if you wanted as there was no plastic carrier for them) and then broke off the metal flange to separate the pins.  I can't remember what they were called but they were used and sold in the Hal ST6 rtty converter kits I built.

Also you can probably use a regular socket and solder all the pins on the bottom them pull the plastic carrier up and off the pins to do the top then MAYBE you can get that plastic carrier to go back over the pins.

Good luck.

Jim Pruitt


On Thu, Feb 16, 2017 at 7:47 PM, roylowenthal@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
 

It used to be possible to get IC sockets that were solderable from both sides. The socket pins came up over the side of the socket, making it (relatively) easy to reach them with a small iron. It's still possible to find sockets that have long enough pins to be solderable from both sides if they're not mounted flush with the board.


Roy


Re: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

2017-02-17 by Roland Harriston

Hello Jim Pruitt:

Could you be referring to "MOLEX PINS"?

Years ago I purchased a bag-full of these items from a now defunct electronics mail order supplier.

I still have a few of them, and use them as required.
You can make any size IC socket you require using these pins.

Regards,

Roland F. Harriston
*********************
On 2/17/2017 10:14 AM, Jim Pruitt jpruitt67@... [Homebrew_PCBs] wrote:
 

In the 70's I bought some strips of ic pins.  You broke off the number you needed per row and stuck them in the holes and soldered them (top and bottom if you wanted as there was no plastic carrier for them) and then broke off the metal flange to separate the pins.  I can't remember what they were called but they were used and sold in the Hal ST6 rtty converter kits I built.


Jim Pruitt



Re: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

2017-02-17 by Jim Pruitt

Hello Roland.
Yes, they were/are Molex pins.  I still have 2 strips of 100 but don't really like them without the plastic cover.  I know that Molex later sold the plastic cover strips but I don't  have any.

I did not say Molex pins because that is so generic now as Molex makes a lot of different pins and most have nothing to do with IC sockets.

Thank you.
Jim Pruitt


On Fri, Feb 17, 2017 at 9:39 AM, Roland Harriston rolohar@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
 

Hello Jim Pruitt:

Could you be referring to "MOLEX PINS"?

Years ago I purchased a bag-full of these items from a now defunct electronics mail order supplier.

I still have a few of them, and use them as required.
You can make any size IC socket you require using these pins.

Regards,

Roland F. Harriston
*********************

On 2/17/2017 10:14 AM, Jim Pruitt jpruitt67@... [Homebrew_PCBs] wrote:
 

In the 70's I bought some strips of ic pins.  You broke off the number you needed per row and stuck them in the holes and soldered them (top and bottom if you wanted as there was no plastic carrier for them) and then broke off the metal flange to separate the pins.  I can't remember what they were called but they were used and sold in the Hal ST6 rtty converter kits I built.


Jim Pruitt




Re: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

2017-02-17 by Sven Oleson

Hi


I use a lot of Photoshop, and remaking the board wouldn't be all that difficult. The bigger question I have is why would you spend all that time remaking it when according to the website at...


http://www.sol20.org/articles.html


"The article offered free copies of the PCB artwork and drilling guide for the price of a SASE. Glenn Herrmannsfeldt did so back when and was kind enough to send a copy of it for this web site. It should be noted that this isn't he final design and in fact is reported to have quite a few errors."

But if you want to continue, open Photoshop, go to file, and click open. Navigate to your page and open. It will come up with a screen to set your preferences. Use 1200 dpi, and cmyk color, then click on the page you want to open. You'll need to adjust the size of the picture to coronation with the dimensions given in the file. Click on Image, then Image size and manipulate document size until correct dimensions have been achieved.


Now onto the artwork, make a single pad as a layer. Duplicate the layer 8 or 10 times to make a complete chip. Move them to the appropriate places and merge all those layers. Now you have 1 chip. Duplicate that chip 50 times and move them into place. Do the same for the other chip types and you're almost home.


The thin lines will likely be around 20 pixels thick. The thicker ones likely 40. You can do the same thing with layers for North south lines and east west lines. All that's left is the corners and turns.


There's a lot of assuming that the dimensions will be correct when it's made to correct scale. I don't know that they are, but when I redraw artwork like this, that is how I would do it. You will need a seriously accurate printer to get the 20 pixel lines to show up at 1200 dpi, and make it between the socket pads.


Best of luck,


Sven

Re: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

2017-02-17 by Roland Harriston

Jim Pruitt:

Yes. In the "old days" Molex only had one or two products. Now, they cover the field.
I had some of those plastic "hoods" that slipped over the pins  but I never used them.
Once the IC is properly inserted into the pins, there is virtually no movement of the
pins or the IC.  So I never thought that the covers were necessary.

Thanks for refreshing my memory.

Regards,

Roland F. Harriston
****************


On 2/17/2017 11:33 AM, Jim Pruitt jpruitt67@... [Homebrew_PCBs] wrote:
 
Hello Roland.
Yes, they were/are Molex pins. 

Re: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

2017-02-17 by Harvey Altstadter




-------- Forwarded Message -------- Subject: Re: [Homebrew_PCBs] Good techniques for cleaning up old artwork? Date: Fri, 17 Feb 2017 13:27:40 -0700 From: Harvey Altstadter <harveyalt@...> To: Homebrew_PCBs@yahoogroups.com

What you are looking for is machined socket pins. They are a metal cylinder with a solder pin on the bottom, and a recessed contact in the top. They are made by Mill-Max and others. I found these on ebay by searching for machined socket pins: http://www.ebay.com/itm/MACHINE-PIN-SOCKETS-SOLDER-TAIL-100-PCS-/222176780627?hash=item33bac4a153:g:FwUAAOSwOVpXesIn

Another possibility is to get some IC sockets with machined pins, mount and solder the bottom side. Then, with a heat gun, heat the plastic portion of the socket until it softens and you can pull it off. The top pads will then be available for soldering. The advantage of doing it this way, is that the socket pins will all line up. The same search on ebay produces many listings for sockets and headers that use pins with this construction. You might also find them cheaper in listings from some of the surplus outlets.

The is another version of this type of contact, but I couldn't find a listing. These are physically smaller, and come on a strip that is peeled away after soldering. I have used them, but I found that they were such low profile, that I sometimes filled the contact with solder when I was doing the top side.

Harvey
On 2/16/2017 8:47 PM, roylowenthal@... [Homebrew_PCBs] wrote:
 

It used to be possible to get IC sockets that were solderable from both sides. The socket pins came up over the side of the socket, making it (relatively) easy to reach them with a small iron. It's still possible to find sockets that have long enough pins to be solderable from both sides if they're not mounted flush with the board.


Roy

RE: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

2017-02-18 by keith printy

Heathkit used those in some kits.i used to have reliability issues with them and had to reseat the chips. Better off to use the sockets with the round tooled pins for best reliability

 

 

From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com]
Sent: Friday, February 17, 2017 1:34 PM
To: Homebrew_PCBs@yahoogroups.com
Subject: Re: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

 

 

Hello Roland.

Yes, they were/are Molex pins.  I still have 2 strips of 100 but don't really like them without the plastic cover.  I know that Molex later sold the plastic cover strips but I don't  have any

I did not say Molex pins because that is so generic now as Molex makes a lot of different pins and most have nothing to do with IC sockets.

Thank you.

Jim Pruitt

 

On Fri, Feb 17, 2017 at 9:39 AM, Roland Harriston rolohar@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:

 

Hello Jim Pruitt:

Could you be referring to "MOLEX PINS"?

Years ago I purchased a bag-full of these items from a now defunct electronics mail order supplier.

I still have a few of them, and use them as required.
You can make any size IC socket you require using these pins.

Regards,

Roland F. Harriston
*********************

On 2/17/2017 10:14 AM, Jim Pruitt jpruitt67@... [Homebrew_PCBs] wrote:

 

 

In the 70's I bought some strips of ic pins.  You broke off the number you needed per row and stuck them in the holes and soldered them (top and bottom if you wanted as there was no plastic carrier for them) and then broke off the metal flange to separate the pins.  I can't remember what they were called but they were used and sold in the Hal ST6 rtty converter kits I built.

 

Jim Pruitt

 

 

 

Re: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

2017-02-18 by Jim Pruitt

I still say the best sockets by far for soldering under are wirewrap sockets.  Yes they have square pins but the leads are about an inch long and so you can raise the socket up as far as you want (if there are no other constraints).  Again you might have trouble finding 18, 20, 22, 24, 28 pin .3" row spacing sockets but I suspect they are available but the 8, 14, 16 pin narrow spacing (.3" row spacing) are available and have been for decades as are the 24, 28, and 40 pin wide row spacing (.6").

Most ic socket pins are inserted into the plastic carriers from the bottom so you can usually place the socket and solder the bottom of the pc board then lift the plastic carrier so you can access the top of the pins.  You have to be careful not to use too much solder on the top of the board or the plastic carrier won't go back over the pins.

With the above paragraph, if you cannot place the plastic carrier back over the pins then you basically have the Molex pins/strips we have been talking about so you can still insert the ic into the pins...assuming you did not use too much solder and did not let it wick up into the part of the socket that the ic pin fits into and clamps against.

Thank you.
Jim Pruitt


On Sat, Feb 18, 2017 at 8:51 AM, 'keith printy' keethpr@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
 

Heathkit used those in some kits.i used to have reliability issues with them and had to reseat the chips. Better off to use the sockets with the round tooled pins for best reliability

 

 

From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@ yahoogroups.com]
Sent: Friday, February 17, 2017 1:34 PM
To: Homebrew_PCBs@yahoogroups.com
Subject: Re: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

 

 

Hello Roland.

Yes, they were/are Molex pins.  I still have 2 strips of 100 but don't really like them without the plastic cover.  I know that Molex later sold the plastic cover strips but I don't  have any

I did not say Molex pins because that is so generic now as Molex makes a lot of different pins and most have nothing to do with IC sockets.

Thank you.

Jim Pruitt

 

On Fri, Feb 17, 2017 at 9:39 AM, Roland Harriston rolohar@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com > wrote:

 

Hello Jim Pruitt:

Could you be referring to "MOLEX PINS"?

Years ago I purchased a bag-full of these items from a now defunct electronics mail order supplier.

I still have a few of them, and use them as required.
You can make any size IC socket you require using these pins.

Regards,

Roland F. Harriston
*********************

On 2/17/2017 10:14 AM, Jim Pruitt jpruitt67@... [Homebrew_PCBs] wrote:

 

 

In the 70's I bought some strips of ic pins.  You broke off the number you needed per row and stuck them in the holes and soldered them (top and bottom if you wanted as there was no plastic carrier for them) and then broke off the metal flange to separate the pins.  I can't remember what they were called but they were used and sold in the Hal ST6 rtty converter kits I built.

 

Jim Pruitt

 

 

 


Re: [Homebrew_PCBs] Good techniques for cleaning up old artwork?

2017-02-21 by Harvey Altstadter


I am resending this post because I was having trouble with my mail when I sent it originally, and I don't think it was posted. Please forgive me if this turns out to be a duplicate.

Brad,

From your description of using the rectangle tool for remaking the traces, it sounds like you are using raster draw tools. If this is so, have you tried to use the vector draw tools in Photoshop? I don't use Photoshop, my preference is for PaintShop Pro, but I know that Photoshop has vector drawing tools similar to those in PaintShop. With the vector tools, you can draw the traces in continuous lines or segments that join together. Curves can be made with tool specially made of them, and joined to the straight segments. Objects like the IC pads are made by combining rectangles and circles, and filling them in. Objects like pads and IC layouts can be saved as objects, and reused.This is much less tedious than trying to draw overlapping rectangles. The down side to vector tools is that there is a bit of a learning curve, but I believe that it is worth it.

If you want to discuss the vector tools and techniques in detail, send me a private message at: hrconsult at cox.net

Harvey


On 2/15/2017 6:04 PM, 'Brad' unclefalter@... [Homebrew_PCBs] wrote:
 

My TV Typewriter project is getting close to the finish line so I’m working on lining up a new project.

 

What I’d like to do next is a replica of the SOL terminal prototype that appeared in Popular Electronics in July of 1976.  I have the artwork for it here:

 

http://www.sol20.org/articles/img/PE_SOL.pdf

 

As you can see, the quality of the scan is pretty lousy.  There’s no other sources for this that I’ve found.  I can clean it up manually with Photoshop or Illustrator (and in fact have started on the former) but that will take hours (months, probably).  I’m wondering if there’s a better technique than endlessly using the rectangle tool to remake the traces and remote the ‘noise’.

 

I expect there will be other challenges, being that this is a double sided board.  There *isn’t* a way for a home PCB maker to do thru-plate without third party help is there?  I don’t want to send this off to a board house because of the likely cost but also because that’s not how a hobbyist would have done it back then.  Since this artwork was sent to those that wrote in for it, I’m assuming they just created it as a two sided board the usual way and then soldered in the connections between sides via ICs, jumper wire, etc.

 

I also don’t want to completely redraw the thing.  For me, that would lose the spiritual connection to the original artwork.  I’m trying to leave as much of it as original as possible.

 

Anyway, thoughts and suggestions here are most welcome.