This symptom is very common in Expeditionpcb 2007.X, especially when you use 5:5 mm data format and using positive plane. Self-intersecting polygon also is common in most or gerber data where including planes. CAM tools have a robust algorithim to process SIPs, but Valor's Trilogy 5000 or Genesys 2000 will fails when translate it into the system when your data in 5:5 data format and somtimes Trilogy 5000 7.6.3 will wrongly raster out the data. Following method may be helpful to eliminate SIPs:
1 Never change the desing unit from mm to inch or versa after you have placed shapes
2 Never using a different unit with layout unit to ouputput gerber data
3 avoid to use 5:5 mm or 5:5 mil data format.
4 It's better to add Gencad netlist into your cam data.
In fact, this sympotom also be in other CAD systems . Hope Mentor can improve it soon.
Use x:2mm or x:3 mil data format can make Expedtionpcb to ouput gerber data with no SIPs.Pls let me know it'effectness to your design.
The gerber data is generated using the following settings;
Data type : 274X
Data Mode : Non-modal
Step mode : absolute
data format 3.5
Zero truncation : Leading
Character set : ASCII
Arc Style : Quadrant
Delimiter : *
Comments : On
Sequence numbering : off
Unit : mm
Polygon fill method: raster
The design is also in mm.
Changing the settings does not affect the polygon created. But, you can overcome this problem by loading the data into Gerbtool and do an "Export Gerber". This is nice as a workaround, but the data generated in the first place should be without any problem. I have created a SR on this issue and we will see what happens next.
Very thanks. Yeas ago, I have logged SRs and attached test data,but Mentor never give me any reply. I think SIP problem was caused by Mentor's plane date generating algolithm. Because We used to use 5:5 format and positive planes, so Valor always warning SIPs to 60%+ gerber data . After changing to 3:2(mm) and regenerated all plane data(setting all plane type to dynamic), most should be OK.