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Intersecting Lines? 1

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majora

Industrial
Apr 19, 2006
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Sometimes my job requires me to scale dxf files from a customer and use for production, for a laser cutting operation. It is important that all the lines in my drawings connect. The problem I keep running into is that the files I receive not all the lines connect, the only way I know how to check all the points is to select all the object line and check all the intersections one by one. Is there a quicker way to do this? You can imagine for the bigger parts this could take a while to check the whole drawing. Please help.
 
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it seems that you may be assuming some liability that you shouldn't by interpretation of poorly constructed dxf files. Rather than trying to fix the files, you may want to bring this to the attention of the client who is apparently not providing you with sufficient data for fabrication. I would send them an RFI asking for clarification (new dxf file preferred).
 
I already thought about and have tried requesting better files in the past with this customer. It is normally quicker for me to fix the drawing than to wait for them to do it, I don't always have the time to wait, like with this job. I'm done now and it was a very tedious task, but I would still be waiting on the customer for good files, now I can start production and avoid getting yelled at....I love my job...haha!

I can't believe that ACAD doesn't have a command that checks all the contours for breaks and nonintersecting lines. Oh well.

Thanks for the help, I appreciate it.
 
cvg is right, and my position is that shoddy workmanship should not be accepted. Your problem is an indication that the ACAD drafters are inept.I realize that your clients are your bread and butter,nonetheless, talk to your clients about the problem and the additional cost to all of you.
 
PEDIT checks for breaks and nonintersecting lines, but it doesn't go out of its way to help you fix them, or even figure out where they really are.

In my experience, the problem often originates with self- taught drafters who leave "near" on as a running osnap all the time, resulting in .003" gaps everywhere. IMHO, that particular osnap should trigger a red/yellow flashing warning flag in the status bar whenever it's on, and a dialog box explaining how badly it can mess up associative dimensioning and line joins whenever you attempt to turn it on.





Mike Halloran
Pembroke Pines, FL, USA
 
"cvg is right, and my position is that shoddy workmanship should not be accepted"
I agree with this statement 100%. My problem is that I have tried to talk to the engineers about some of these problems, but nothing seems to change. It seems to me that a big company like them doesn’t want to hear suggestions from a small town company. They have a team of drafters, I’m the only drafter that works here…I’m out numbered, haha. I don't know how you might feel about this but this company doesn't use AutoCAD like I do, they use something different (I forget the name of it) so possibly it's something to do with the options in their program or they way they draw with it. I don't know, I'm only speculating on that thought (I do know that they use a different program).

"Your problem is an indication that the ACAD drafters are inept."
I do not think that they are inept. I can safely say that just about all the drafters there have more experience then I do. Like I said above, maybe it is quarks in their program I’m not sure.

I don’t know, maybe one of these days I can get some results. Ultimately I accomplished what I needed to get done without losing more time that needed. Thank you all for your input.
 
the problem you have is easily fixed using a lisp routine. It is not uncommon at least from my experience in GIS applications (ArcInfo) to perform a "clean" operation which automatically joins all lines at intersections and eliminates the undershoots and overshoots. Search any GIS forum and you will probably find an autocad version of the "clean" routine written in AutoLisp.

The problem is, that if you clean up the file and run the laser cutting routine, will the result be acceptable? If not, who will be blamed for the poor result?
 
It would fall back on me if the laser cutting is bad due to the drawing. Maybe I should stick to the method I already use. Good food for thought though, I'll have to look it up and test it out and check the contour. Thanks!
 
You need to be careful with the hatch method. You can invoke BOUNDARY (what hatch uses) and if the hatch doesn't "leak" out, it can go ahead and create the hatch even though the object is not totally enclosed. You can recreate this by drawing a polyline that is just barely open at one corner and then find the BOUNDARY. It will create a polyline boundary even though the contour is not perfectly enclosed.


"The fear of the Lord is the beginning of wisdom"
 
In your pricing and invoicing, just start quoting a standard fee for "Editing of CAD drawings to remove drafting errors".

In fixing things, it may be simpler to turn lines into polylines. Using radius command with zero radius will make two lines meet, whether they did before or not, quicker than Extend on both lines.
 
Depending on the complexity of the part, I use fillet with a radius of zero at the intersecting lines. It saves time not checking, but just makes sure they intersect. If the parts are very complex, it would still take a bit of time to do this.
 
I would tend to try turning the boundries into polylines using the PEDIT command, turning one line into a polyline then choosing 'Join' to connect all the other boundry lines. You will find most of the lines with stick together and where it won't connect with the next line is where the break is.
 
Majora,
I wrote a lisp program some years ago that may be what you need. It works only for simple entities (lines and arcs) in 2D. It marks free endpoints, but does not automatically fix anything. If you are interested, send an email to support@rgmts.com and include "Majora" in the subject line. I will send you the program with a bit of instruction.
 
Just a small point that maybe of interest with the fillet command. Not sure if it just came about in 2006 but if you hold the shift key down when filleting it auto sets radius to zero.
 
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