No Board outline when artwork is made

Every single film had undefined line set at 0.05mm - the outline showed up in none of them. Hence, I suspect this is more a question of my outline being wrong. Something like a rectangle (in the Allegro terms - not the geometrical sense ;-) not being a proper outline. (I still not quite understand why Allegro is so picky with the different types ;-)

Guess I should check some of the other designs - I don't remember it to be problem earlier...

You have always been able add a thickness to a line item not a rectangle in tne Allegro sense. Do you have a photoplot outline Colors - Manufacture  - Photoplot_Outline) set to the same size as the board ? This would probably clip the outline off the artwork, Personally I never use the photoplot outline but if you must make it 1000 mils larger than anything you want in the artwork.

Steve, you are absolutely right: The Photoplot_Outline was the culprit!

I still have a felling that there might be a better "best practice" for this - but using the undefined line width is definitely a fair, usable solution. (Only strange the parameter can only be set one film at a time ;-)

Thanks for the insight! :-D

All,

After reading this thread I felt the urge to respond.  The PHOTOPLOT OUTLINE was used years ago to restrict the output file to a certain length and width.  I think this was used by people that use to put formats on their artworks rather than just a title block. I think most, if not all fabricators read the gerbers into their CAM system where they can check and manipulate anything that they need to.  Then, they will either go directly into the photoplotter or generate their own artworks.   So 99.9% of the time it is not needed.  If it is there, the system will reduce the extents of the gerber data to just that window.  If it is not there, it will use the Film Size Limits specified in the General Parameters section of the Artwork Control Form which I think is 24 x 16.

Next,  I think just about everyone who is fabing boards these days can read 274x format at a bare minimum.  I would not even mess with the old 275 format.  Even better, if you are using CAM350,ADIVA, or Valor to check your artworks, I would be using ODB++ or IPC-2581 if you can.  We have been using ODB++ for over 3 years without any issue and it puts eveything into ONE file.  We even include our Fab Drawing, Board Outlines, Panel Outlines, and anything else we think the fabricator might need.  We leave the board outline  and other things like dimension lines and text on the fab dwg at 0 line width and it still transfers into ODB++.  Heck, even the free ViewMate gerber viewer can read ODB++ data.  Time to get out of the Dark Ages boys and girls.  Just MHO.......;-)   I feel much better now thankyou.

Boma,

Thanks for your thoughts! Actually I think the photoplot outline is a fairly good feature*. As are many of the Allegro features. My main problem is that the help system primarily (only?) waste time - so this forum is ususally a much better help. I try to remember writing notes - at some point someone should read a nice, short "Allegro essentials" guide. It might be out there already - but I failed to find it so far! ;-)

Interesting stuff! I always felt the 274x should be obosolete - but I've never had the energy to convince everybody that it was a sensible move...However, ODB++ surely sounds nice! Checking around I've (unfortunately) found no manufacturer that claims the capability (Macaos, EuroCircuits, PCB123, 'all' the Chinese). And I'm way to small a customer to ever impose anything on a manufacturer.

Regarding "everybody [...] can read 274x", I actually had to give up on Olimex (a small, cheap Bulgarian manufacturer that I've loved to use for simple prototypes and test circuits. And cheap shipping!). The initial response when I changed to Orcad PCB/Allegro was:

"Your gerbers contain composite layers and negative plots (G36 G37 commands).
On such gerbers we can't do DRC check, panelization nor to ensure correct phototools plotting."

After several tries to solve this we had to give up. One manufacturer less to choose from - sadly!

Have a great weekend! :-D

*) PS: I'm fairly convinced that Allegro either made the photoplot outline for me - or reported an error about needing it! At least it does not seem probable I've suddenly felt an urge to create it on impulse... :-P