poly lines in autocad 1

[jimp178]

When I save drawing in Solidworks as dwg .When I open in autocad 2002 the 3D curves come in as thick polylines, any way to solve this problem will be greatly recieved.

Thanks in advance JimP

 

[Theophilus]

I really don't know. However, there are options you can set before making your save. Select DWG format, name your file, then hit Options instead of OK to see what sort of options are being exported. Maybe that will help in solving the problem?




Jeff Mowry
Industrial Designhaus, LLC

http://www.industrialdesignhaus.com

 

[JNR]

It may depend on what type of curve you are translating. For example, a "compound curve" really is to all intents and purposes a "polyline". It is a chain of simple curves aggregated together into one entity. So it makes logical sense to translate that way, given the capabilities of the source (SW) and target (ACAD) systems. It allows you to extract the original definitions. Generally speaking it is not a good idea to try to translate something like that as a single spline approximation. Polylines may (or may not for all I know) be more cumbersome to deal with in ACAD than compound curves in SW, but that is not SW's problem. However, a single line, arc (or spline even) becoming a polyline might concern me.

John Richards Sr. Mech. Engr.
Rockwell Collins Flight Dynamics

Forget rich and famous - I want to be rich and unknown.

 

[murugansubham]

u didn't tell, sketches r somewhat thicker in drawing or drawing prints.
if it is in print , try to change the printer settings.

if it is showing in autocad drawing,

please check tools-options-line font for sketch curves line thickess.

thanks,

Regards,
Murugan.S
Sr. Design Engineer,
CAD/CAM Research Center,
GlobalSoft Pvt Ltd,
New Delhi, INDIA.

 

[jimp178]

Thanks for all your input, I have tried the options but the problem is still their. I have drawn a spere and cut a hole thro the centre in Autocad the hole in the ISO view comes in with thick poly lines, what I don't understand either is that it seems to print with correct line widths. Maybe its a Autocad problem?

What I like best about this forum is that Iam working in Scotland yet can recieve help from every corner of the world. Keep up the good work.

JimP

 

[JNR]

When you say "....cut a hole thro the center in AutoCad the hole...." I assume you mean ".....cut a hole through he center in SW and when you transfer it to Autocad.......", yes?

Well there is probably a simple reason for that. Since you are cutting a sphere, the edge produced is a spline, not a circle. True it is a circle in theory if it is a circular hole and it's axis is coincident with the center of the sphere. However that is a special case and I doubt that SW looks for that special case every time you cut a hole which could be any shape in a body which might have been created by a number of methods. And when you transfer that 3D spline there is no reason why either end of the transfer should be looking for a special case to see if a general closed spline might just happen to be a circle (and even if it did, what tolerance would you what it to assign to the circularity test, hmmm?)

While Solidworks does in fact look for the special case INTERNALLY when doing measure dimension, etc. that is on an individual command basis and can afford the time to look and it can use the definition data for the feature (don't know if they do, but they could). When converting to other CAD systems, bear in mind that the transfer is coming from a Parasolid model definition and the feature data does not transfer and is irrelevent.

Hope that made sense. I read it over and can't think of a better way to phrase it.

John Richards Sr. Mech. Engr.
Rockwell Collins Flight Dynamics

Forget rich and famous - I want to be rich and unknown.

 

[jimp178]

Thanks for your explanation John, I understand what you are saying, and yes you assume right (I assume you mean ".....cut a hole through he center in SW and when you transfer it to Autocad.......", yes?)

I get the thick polylines with all splines when transfered to autocad with 2004 SP0.0. I only made the sphere to try and explain to the forum my problem.
I have just tried the same part in solidworks 2003 generating a drawing and transfering to autocad, and the drawing is perfect with no thick lines?

Thanks JimP

 

[JNR]

It must be something in the way Autocad handles line font as opposed to how SW does it. Autocad has a lot of layer based properties and other fonting abilities related to plotting, because it came from the time when pen plotters were the only option. SW does deal somewhat with color and layer these days but it is only in there due to import export needs (even if people do use it for other things now they have it). I have not had to deal with this in SW, but typically CAD systems would have some sort of data configuration file option for layer/color/pen thickness conversion to DXF, etc. Does SW have something like this? If so this is probably where you can fix the problem. Sounds like they have a default setting changed from 2003.

John Richards Sr. Mech. Engr.
Rockwell Collins Flight Dynamics

There are only 10 types of people in the world - those who understand binary and those who don't.

 

[mncad]

Jim,

I believe it is an Autocad problem because I have noticed the same problem since we went to SW2004. It is easy enough to fix in Autocad by selecting the polyedit command. Then select multiple on the command line, now select all the lines in the file using a window. After you have selected them it will ask if you want to convert lines and arcs to polylines, select no. Now you will have several choices, 1 of them being width. Enter a "w" then give it a width of 0. Should give you the results you are looking for.

mncad