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How to force PCB Designer to update existing design padstacks with newly added drill tolerances?

bengelJF

Title says it all really.

I need to go back and add tolerances to various drills in the drill table per the board house's request. It's easy enough to go into the padstack file and add those tolerances, but I haven't had any luck forcing OrCAD to pull these tolerances into an existing design. I've tried padstack refreshes, symbol refreshes, going into the footprint file for the part and refreshing padstacks there, all with no luck.

An existing workaround is to customize the drill table after the layout is complete, and the correct way to handle this is to have the tolerances in the padstack in the first place; however, we have existing designs that we need to update. Updating the padstacks in question with a method that I can pass on to the rest of the team would be the ideal solution.

Thanks!

Parents
  • +1

    Hi, Update your symbols with the new padstacks first. Verify that when the Symbol is updated it does reflect the correct padstack is in use. All of this is done in the symbol editor.

    On the PCB Database you wish to update with the newer symbols choose. Update symbols and then select the package symbols you wish to update. Lastly check the options, Update Symbol Padstacks from library and also check "Reset Customizable Drill Data" Press refresh to run and update the board with the new information.

    With respect to the tolerances of the drill. How are you going to actually control that ?. Beyond calling out the actual drill size you wish to use for a given hole size you cant really control the tolerance during manufacture because you don't know or may not know the actual run-out of the drill machine etc. I think it is best to negate the tolerance and just specify the actual drill size that will be used. It is up to the board house to pick a suitable drill bit size to match what you specify.

    Best regards.

Reply
  • +1

    Hi, Update your symbols with the new padstacks first. Verify that when the Symbol is updated it does reflect the correct padstack is in use. All of this is done in the symbol editor.

    On the PCB Database you wish to update with the newer symbols choose. Update symbols and then select the package symbols you wish to update. Lastly check the options, Update Symbol Padstacks from library and also check "Reset Customizable Drill Data" Press refresh to run and update the board with the new information.

    With respect to the tolerances of the drill. How are you going to actually control that ?. Beyond calling out the actual drill size you wish to use for a given hole size you cant really control the tolerance during manufacture because you don't know or may not know the actual run-out of the drill machine etc. I think it is best to negate the tolerance and just specify the actual drill size that will be used. It is up to the board house to pick a suitable drill bit size to match what you specify.

    Best regards.

Children
  • 0 in reply to excellon1

    Thanks, this solution worked for me.

    As for the drill tolerance, in many instances the manufacturer of the component we're using will specify a tolerance in the finished hole size. It's very rare that they actually specify a drill size in addition to a finished size + tolerance; I've only seen that in press-fit connectors so far. Our board house told us they can't quote for our board with press-fit connectors unless everything has a tolerance, so we end up here.

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