Operations and Manually Nested Drawings

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David_Lelen01
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Operations and Manually Nested Drawings

Post by David_Lelen01 » Mon Oct 07, 2019 4:54 pm

Hey Les, i have a few things ive noticed again lately... may be bugs or may be possible suggested improvements.

1) When breaking up a manually nested drawing, each generated part starts with a rapid from the machine origin. I don't see where this causes a problem with the cutting process, but it makes the rapid distance and time in the reports grossly incorrect.

2) When breaking up a manually nested drawing, if there are 280 parts nested, 280 separate parts are made and the job report shows 280 individual parts instead of 1 part being cut 280 times. This makes the job report numerous pages long and also makes further editing of operations extremely time consuming.

3) When breaking up a manually nested drawing, open contours (lines that are used for etching on our laser) are interpreted as separate parts. Saving each part in the nest as a block does not affect this.

4) The operations list is specific to each part and not each layer. I remember reading a post about this somewhere in the forum, but cannot find it now and i do not remember the outcome. But if i break up a manually nested drawing with 280 parts and then realize i need to change a leadin, then i have to change it 280 times or start over. This is extremely time consuming.

5) The leadins of parts in a manually nested drawing that has been broken up sometimes overlap other parts in the nest. Obviously, this causes a big problem.

6) Could a setting or checkbox or something be added in the operations dialog to choose the optimum start point location of an operation. I remember reading another post about start points and i cannot find it either. But it seems a lot of times, the start points are placed on corners of parts when it would best be placed in the middle of a straight edge or vise versa. Could a setting be added to choose corners, centers of edges, arcs, etc.?

7) Would it be possible to add an option to the import drawing dialog to rotate the drawing 90, 180, 270 degrees? I know this can be done with the nesting mode, but if you know it needs to be rotated when you open it would be helpful too.

If you need any more details or explanation of these, let me know.

Thanks for everything you have done Les!

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Les Newell
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Re: Operations and Manually Nested Drawings

Post by Les Newell » Mon Oct 07, 2019 5:23 pm

David_Lelen01 wrote:
Mon Oct 07, 2019 4:54 pm
1) When breaking up a manually nested drawing, each generated part starts with a rapid from the machine origin. I don't see where this causes a problem with the cutting process, but it makes the rapid distance and time in the reports grossly incorrect.
You only see this when you edit individual parts. If you switch to nesting mode you will see the actual tool path that will be generated which does not have all of the rapids starting at the origin. Simulation and estimate use the actual tool path.
2) When breaking up a manually nested drawing, if there are 280 parts nested, 280 separate parts are made and the job report shows 280 individual parts instead of 1 part being cut 280 times. This makes the job report numerous pages long and also makes further editing of operations extremely time consuming.
Yes it will because 'break up manually nested drawing' pulls individual parts out of a nested drawing. It does not detect duplicated parts so as far as it is concerned each part is different.
3) When breaking up a manually nested drawing, open contours (lines that are used for etching on our laser) are interpreted as separate parts. Saving each part in the nest as a block does not affect this.
Straight lines are a problem if they are outside of an outline. Part detection works by finding the outermost outlines. Each outermost outline and any lines within it are considered to be one part. If you have open lines outside a closed outline SheetCam has no way of detecting what part they belong to.
4) The operations list is specific to each part and not each layer. I remember reading a post about this somewhere in the forum, but cannot find it now and i do not remember the outcome. But if i break up a manually nested drawing with 280 parts and then realize i need to change a leadin, then i have to change it 280 times or start over. This is extremely time consuming.
Yes, that is a problem. Linking operations between parts gets very complicated as SheetCam's architecture was never designed to handle that.
5) The leadins of parts in a manually nested drawing that has been broken up sometimes overlap other parts in the nest. Obviously, this causes a big problem.
Currently leadins are only aware of outlines within the current part, not any nearby nested parts. Making them aware of nearby parts is an issue because duplicated parts are simple step-and-repeat copies of the original part. When you have multiple duplicates, which one do you use for your leadin checks?
6) Could a setting or checkbox or something be added in the operations dialog to choose the optimum start point location of an operation. I remember reading another post about start points and i cannot find it either. But it seems a lot of times, the start points are placed on corners of parts when it would best be placed in the middle of a straight edge or vise versa. Could a setting be added to choose corners, centers of edges, arcs, etc.?
Currently if favours corners because starting along a straight line often leaves a visible mark on the finished part. Perhaps I need to look into making this user configurable.

David_Lelen01
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Re: Operations and Manually Nested Drawings

Post by David_Lelen01 » Mon Oct 07, 2019 6:44 pm

You only see this when you edit individual parts. If you switch to nesting mode you will see the actual tool path that will be generated which does not have all of the rapids starting at the origin. Simulation and estimate use the actual tool path.
That is interesting. Could the job report somehow be using the origin. Because when i ROUGHLY estimate the total rapid distance, i get about half of what the job report is saying. I attached the job file in case you have time to look at it.
Yes it will because 'break up manually nested drawing' pulls individual parts out of a nested drawing. It does not detect duplicated parts so as far as it is concerned each part is different.
I take it that would be a massive challenge to detect duplicate parts?
Straight lines are a problem if they are outside of an outline. Part detection works by finding the outermost outlines. Each outermost outline and any lines within it are considered to be one part. If you have open lines outside a closed outline SheetCam has no way of detecting what part they belong to.
None of the lines having the problem are outside of a closed contour. Attached is that job file as well.
Currently leadins are only aware of outlines within the current part, not any nearby nested parts. Making them aware of nearby parts is an issue because duplicated parts are simple step-and-repeat copies of the original part. When you have multiple duplicates, which one do you use for your leadin checks?
Perhaps check all parts within twice the leadin distance. I'm sure that is easier said than done as well.
Currently if favours corners because starting along a straight line often leaves a visible mark on the finished part. Perhaps I need to look into making this user configurable.
Typically that is true, however for laser machines that is not an issue. It actually, contrary to what i believed as well, cuts better with a perpendicular leadin in the middle of a straight edge.
Attachments
OpenContours.job
(135.66 KiB) Downloaded 8 times
RapidLength.zip
(69.86 KiB) Downloaded 8 times

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Les Newell
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Re: Operations and Manually Nested Drawings

Post by Les Newell » Tue Oct 08, 2019 11:04 am

David_Lelen01 wrote:
Mon Oct 07, 2019 6:44 pm
That is interesting. Could the job report somehow be using the origin. Because when i ROUGHLY estimate the total rapid distance, i get about half of what the job report is saying. I attached the job file in case you have time to look at it.
Simulation, toolpaths in nesting and job report are all specialized post processors. They all receive the same tool paths as any other post processor.
I take it that would be a massive challenge to detect duplicate parts?
Yes. Due to the way computers store floating point numbers the duplicates can vary slightly. These variations are far too small to affect the finished parts but they make it difficult to directly compare coordinates. I'm not even going to start on the difficulties in comparing rotated parts...
None of the lines having the problem are outside of a closed contour. Attached is that job file as well.
The problem lines start and end exactly on the outline. In this case the inside/outside detection can have trouble. If you move the starts and ends so they are slightly inside the outline SheetCam should have a better chance of detecting them.
Typically that is true, however for laser machines that is not an issue. It actually, contrary to what i believed as well, cuts better with a perpendicular leadin in the middle of a straight edge.
That is useful information. I'll look into making the optimisation more configurable.

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