Topics

Eagle-polygons-rectangles

Roy Emeny
 

Hi Paul,

Thanks for your info.  Interested in the ultrasonic cleaner - often seen them advertised (maplin) and wondered if they do much. Gosh the dunk in etchant seems a bit aggressive - would something like meths then ultrasonic do anything?
I make a solution of meths and crushed violin bow resin (roson?) to wipe over board to stop oxidisation after cleaning.

Prompted by your suggestion I did try the rectangles on various layers but then the rectangles and the original tracks both got milled by pcb-gcode.  I wonder if there is an eagle command to shift all items on one layer to another. If there was the rectangles could be created on a separate one and then shifted and rat-nested just before milling, this would allow you to see the original tracks to check validity until the last possible minute. However as Martin points out I am probably heading up a blind ally here!

Roy  




On Wednesday, 5 February 2014, 16:50, Paul Kiedrowski wrote:
 
Hi Roy,
What you describe is an issue, the little slivers, yes. Increasing isolation really isn't always a solution since it usually just changes where they occur. What I do is just ignore them and address it after the board is milled by wire brushing then snipping them out with an exacto knife. I also snip off the little acute angled "tips" of copper that sometimes occur and tend to raise up a bit. Finally I sometimes soak the board in etchant for a couple minutes and then in an ultrasonic cleaner before soldering begins.
 
I haven't tried it but you might try drawing your rectangles on what the ULP calls the "milling layer" instead of the actual copper layers. This layer is used for adding text and routing the board outline.  On that layer I don't think you have to name them since they are just lines.  Just remember the tool will follow the lines as its centerline. I suppose you'de have to draw the rectangles two times, once for milling top, then bottom sides. But should be easy.
 
-Paul

From: Roy Emeny
To: pcb-gcode@...
Sent: Friday, January 31, 2014 7:02 AM
Subject: [pcb-gcode] Eagle-polygons-rectangles [1 Attachment]

 
[Attachment(s) from Roy Emeny included below]
Hi
Sorry if there is an answer elsewhere - found lots of references but nothing helpful.
Having a great time making PCBs thanks to Eagle and pcb-gcode.
Problem using Eagle conventionally is it produces nice looking boards but often tiny areas of copper are left between tracks and around components. These can give rise splinters and shorts.
My mill isn't the most accurate - so simple functional, non-artistic boards are fine by me. The best method I have found so far is create ground planes on both sides using polygons with thermals off - (thanks for previous help in this respect). Then routing the board with thin tracks so I can see how everything connects on both sides. Then filling the board with rectangles over these thin tracks on either top or bottom layer - rectangles are so quick with only two defined points (using alt and finest grid setting).
Milled results are good and tend to contain only half as many gcode instructions, thus quicker.  By ensuring that the gap between adjacent rectangles is only say 0.2 mm the mill effectively goes in almost the same path twice clearing any splinters.
But there is an issue, because you can't name a rectangle as you can a polygon, Eagle doesn't recognise them as part of your nets so they can't be speedily ripped up. There is also a danger of nudging them out of place when moving component names etc when tidying up an eagle file to pass on to others. I wonder what others are doing? Is there a way of naming rectangles or creating a polygons as quickly? - I find the latter very fiddly and slow to use for creating in large quantities.  Have attached a jpg - as you will see the quality of my soldering doesn't warrant an artistic board - really must get a new poker ....

Roy




Danny Miller <dannym@...>
 

After engraving, I may give it a rubbing with a 3M green abrasive scrubber (not the "nonscratching" one which has no abrasive).  This tends to lift up slivers.

There are two sources of slivering in the algorithm.  ONE souce, which is like 95% of the problem, can be completely prevented by changing the "Step size" to less than 1/2 the bit's cutting width.  Unfortunately this almost doubles the runtime- but it DOES work.

What that does is guarantee that in any clearance between 2 copper features which is LESS than 2x the Maximum value, it won't stop with the last 2 toolpath loops less than 1 cutting width apart, i.e. a "sliver".

The situation still NOT addressed is if the 2 copper features are just SLIGHTLY more than 2x the Maximum apart.  The stepping algorithm will stop once it reaches Maximum, but they have to be separated by precisely the right (wrong) amount to have a remainder at all.  If it's even slightly more, then the remaining copper will be structurally sound like we want and won't peel off into a thread that shorts things out.

But that latter case is rare.

Danny

On 2/5/2014 4:52 PM, Roy Emeny wrote:
 
Hi Paul,

Thanks for your info.  Interested in the ultrasonic cleaner - often seen them advertised (maplin) and wondered if they do much. Gosh the dunk in etchant seems a bit aggressive - would something like meths then ultrasonic do anything?
I make a solution of meths and crushed violin bow resin (roson?) to wipe over board to stop oxidisation after cleaning.

Prompted by your suggestion I did try the rectangles on various layers but then the rectangles and the original tracks both got milled by pcb-gcode.  I wonder if there is an eagle command to shift all items on one layer to another. If there was the rectangles could be created on a separate one and then shifted and rat-nested just before milling, this would allow you to see the original tracks to check validity until the last possible minute. However as Martin points out I am probably heading up a blind ally here!

Roy  




On Wednesday, 5 February 2014, 16:50, Paul Kiedrowski wrote:
 
Hi Roy,
What you describe is an issue, the little slivers, yes. Increasing isolation really isn't always a solution since it usually just changes where they occur. What I do is just ignore them and address it after the board is milled by wire brushing then snipping them out with an exacto knife. I also snip off the little acute angled "tips" of copper that sometimes occur and tend to raise up a bit. Finally I sometimes soak the board in etchant for a couple minutes and then in an ultrasonic cleaner before soldering begins.
 
I haven't tried it but you might try drawing your rectangles on what the ULP calls the "milling layer" instead of the actual copper layers. This layer is used for adding text and routing the board outline.  On that layer I don't think you have to name them since they are just lines.  Just remember the tool will follow the lines as its centerline. I suppose you'de have to draw the rectangles two times, once for milling top, then bottom sides. But should be easy.
 
-Paul

From: Roy Emeny
To: pcb-gcode@...
Sent: Friday, January 31, 2014 7:02 AM
Subject: [pcb-gcode] Eagle-polygons-rectangles [1 Attachment]

 
[Attachment(s) from Roy Emeny included below]
Hi
Sorry if there is an answer elsewhere - found lots of references but nothing helpful.
Having a great time making PCBs thanks to Eagle and pcb-gcode.
Problem using Eagle conventionally is it produces nice looking boards but often tiny areas of copper are left between tracks and around components. These can give rise splinters and shorts.
My mill isn't the most accurate - so simple functional, non-artistic boards are fine by me. The best method I have found so far is create ground planes on both sides using polygons with thermals off - (thanks for previous help in this respect). Then routing the board with thin tracks so I can see how everything connects on both sides. Then filling the board with rectangles over these thin tracks on either top or bottom layer - rectangles are so quick with only two defined points (using alt and finest grid setting).
Milled results are good and tend to contain only half as many gcode instructions, thus quicker.  By ensuring that the gap between adjacent rectangles is only say 0.2 mm the mill effectively goes in almost the same path twice clearing any splinters.
But there is an issue, because you can't name a rectangle as you can a polygon, Eagle doesn't recognise them as part of your nets so they can't be speedily ripped up. There is also a danger of nudging them out of place when moving component names etc when tidying up an eagle file to pass on to others. I wonder what others are doing? Is there a way of naming rectangles or creating a polygons as quickly? - I find the latter very fiddly and slow to use for creating in large quantities.  Have attached a jpg - as you will see the quality of my soldering doesn't warrant an artistic board - really must get a new poker ....

Roy





Roy Emeny
 

Hi Danny,

Thanks for the comments - from your reaction and the others it is clear that what I should be addressing is getting my mill moving faster then extra passes would not be the issue that they are at present.  This means solving the sudden loss of X registration commented on in a previous email.  Perhaps I need to start a new thread to see if anyone else has had a similar experience that might help me find the fault. Would this be appropriate on this forum or is it too far off topic?
Thanks to everyone who has responded re the rectangles issue - it has given me a different perspective.
Roy


On Thursday, 6 February 2014, 0:33, Danny Miller wrote:
 
After engraving, I may give it a rubbing with a 3M green abrasive scrubber (not the "nonscratching" one which has no abrasive).  This tends to lift up slivers.

There are two sources of slivering in the algorithm.  ONE souce, which is like 95% of the problem, can be completely prevented by changing the "Step size" to less than 1/2 the bit's cutting width.  Unfortunately this almost doubles the runtime- but it DOES work.

What that does is guarantee that in any clearance between 2 copper features which is LESS than 2x the Maximum value, it won't stop with the last 2 toolpath loops less than 1 cutting width apart, i.e. a "sliver".

The situation still NOT addressed is if the 2 copper features are just SLIGHTLY more than 2x the Maximum apart.  The stepping algorithm will stop once it reaches Maximum, but they have to be separated by precisely the right (wrong) amount to have a remainder at all.  If it's even slightly more, then the remaining copper will be structurally sound like we want and won't peel off into a thread that shorts things out.

But that latter case is rare.

Danny

On 2/5/2014 4:52 PM, Roy Emeny wrote:
 
Hi Paul,

Thanks for your info.  Interested in the ultrasonic cleaner - often seen them advertised (maplin) and wondered if they do much. Gosh the dunk in etchant seems a bit aggressive - would something like meths then ultrasonic do anything?
I make a solution of meths and crushed violin bow resin (roson?) to wipe over board to stop oxidisation after cleaning.

Prompted by your suggestion I did try the rectangles on various layers but then the rectangles and the original tracks both got milled by pcb-gcode.  I wonder if there is an eagle command to shift all items on one layer to another. If there was the rectangles could be created on a separate one and then shifted and rat-nested just before milling, this would allow you to see the original tracks to check validity until the last possible minute. However as Martin points out I am probably heading up a blind ally here!

Roy  




On Wednesday, 5 February 2014, 16:50, Paul Kiedrowski mailto:paul_kiedrowski@... wrote:
 
Hi Roy,
What you describe is an issue, the little slivers, yes. Increasing isolation really isn't always a solution since it usually just changes where they occur. What I do is just ignore them and address it after the board is milled by wire brushing then snipping them out with an exacto knife. I also snip off the little acute angled "tips" of copper that sometimes occur and tend to raise up a bit. Finally I sometimes soak the board in etchant for a couple minutes and then in an ultrasonic cleaner before soldering begins.
 
I haven't tried it but you might try drawing your rectangles on what the ULP calls the "milling layer" instead of the actual copper layers. This layer is used for adding text and routing the board outline.  On that layer I don't think you have to name them since they are just lines.  Just remember the tool will follow the lines as its centerline. I suppose you'de have to draw the rectangles two times, once for milling top, then bottom sides. But should be easy.
 
-Paul

From: Roy Emeny mailto:forjacdf@...
To: pcb-gcode@...
Sent: Friday, January 31, 2014 7:02 AM
Subject: [pcb-gcode] Eagle-polygons-rectangles [1 Attachment]

 
[Attachment(s) from Roy Emeny included below]
Hi
Sorry if there is an answer elsewhere - found lots of references but nothing helpful.
Having a great time making PCBs thanks to Eagle and pcb-gcode.
Problem using Eagle conventionally is it produces nice looking boards but often tiny areas of copper are left between tracks and around components. These can give rise splinters and shorts.
My mill isn't the most accurate - so simple functional, non-artistic boards are fine by me. The best method I have found so far is create ground planes on both sides using polygons with thermals off - (thanks for previous help in this respect). Then routing the board with thin tracks so I can see how everything connects on both sides. Then filling the board with rectangles over these thin tracks on either top or bottom layer - rectangles are so quick with only two defined points (using alt and finest grid setting).
Milled results are good and tend to contain only half as many gcode instructions, thus quicker.  By ensuring that the gap between adjacent rectangles is only say 0.2 mm the mill effectively goes in almost the same path twice clearing any splinters.
But there is an issue, because you can't name a rectangle as you can a polygon, Eagle doesn't recognise them as part of your nets so they can't be speedily ripped up. There is also a danger of nudging them out of place when moving component names etc when tidying up an eagle file to pass on to others. I wonder what others are doing? Is there a way of naming rectangles or creating a polygons as quickly? - I find the latter very fiddly and slow to use for creating in large quantities.  Have attached a jpg - as you will see the quality of my soldering doesn't warrant an artistic board - really must get a new poker ....

Roy







Art Eckstein
 

Roy,
As a moderator on this group, I would have no problem with a thread on this subject as it is a common problem with many machines. A lot of times, people will blame the software when in actuality their machine cannot hold necessary tolerances. I personally think this will be a good adjunct to our group. Obviously, JJ can override me, but I would say go for it.

Art
Country Bubba

At 05:29 PM 2/6/2014, you wrote:


Hi Danny,

Thanks for the comments - from your reaction and the others it is clear that what I should be addressing is getting my mill moving faster then extra passes would not be the issue that they are at present. This means solving the sudden loss of X registration commented on in a previous email. Perhaps I need to start a new thread to see if anyone else has had a similar experience that might help me find the fault. Would this be appropriate on this forum or is it too far off topic?
Thanks to everyone who has responded re the rectangles issue - it has given me a different perspective.
Roy

Roy Emeny
 

Art,


I am about to go away for a week, will see if I have email access at the hotel before hitting the group with the full details of  this new question.

Thanks for the encouragement.


Roy