NC drill Setup애서 현재는 # of Digits가 변경이 안됩니다.
대신 Drill Listting쪽에서 Excellon의 설정을 입력하여 출력하는 방법이 있습니다.
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Summary

How to create an Excellon Drill file with 3.5 format?
 How to create an Excellon file with 3 leading and 5 trailing digits?



Details

An Excellon drill machine can only accept a 2.4 format. But, if you would like to be to be able to overlay the drill with the Gerbers, which are generally formatted 3.5, you can do this. You can achieve this by using the NC Drill Setup dialog. Go into File > CAM, and then select your drill output (the NC output, not the Drill Drawing). Click Edit, then Device Setup.
 In here you'll see two tabs, one for Drill Listing, and one for Excellon. Copy ALL the values listed under the "String" column from the Excellon tab to the Drill Listing tab, and then the output will be in Excellon. The Drill Listing option allows you to set leading and trailing values that the standard Excellon output doesn't allow.

 Note: To copy the cell information on the Excellon tab double Click it, then select, then Ctrl+C, repeat on Drill Listing tab but use Ctrl+V.