Jim, End mills or slot drills would certainly be ideal,but if that's not immediately possible the next best results would be with the shortest-fluted drills you have. Also drilling with no more than a single panel stack and with minimum penetration of the drill depth into the backer (good for all kinds of drilling) will achieve better results. Mike Mikucki ______________________________ Reply Separator _________________________________ Subject: Re: [TN] slot drill Author: "Wilmer; Craig" <[log in to unmask]> at SMTPLink-Hadco Date: 1/22/99 10:04 AM Jim, I used to experience the "jagged banana" slot problem also on smaller diameter tools. My intertim solution was to write the slots into the drill program as route sequences provided it was a primary drill operation. This still left some deformity in the panel at the plunge and retract points, but was much better than the CNC G85 command. To minimize the bit deflection deformity, I programmed my plunge and retract points in the center of the slot. I did reduce the feed rate and decreased the panel stack height and this helped slightly, but adding another tool change to the program and decreasing the stack height wasn't very efficient. You might also check to make sure the pressure foot on the spindle is clamping and releasing properly if you use a route sequence. If slots are becoming a way of life with your customers, I recommend installing a copy of FASTechnologies NC-CAM Drill/Route Edit on your workstation and the problem will disappear, provided you have the budget resources. They have the best optimization and slot drilling algorithms bar none. Their S3 slot algorithm makes the G85 command look like a tomahawk approach. When drilling slots even with this product, be sure to slow the feed rate slightly (20-30 IPM)and set the max hit counter on the tool to 1000-1500 (depending on diameter) hits in the program header. This will keep them straight with excellent hole wall characteristics for plating. Here's a link for the product... http://www.fastec.com/drill/drill.htm Regards, Craig Wilmer PCA Product Engineering email: mailto:[log in to unmask] web: http://www.ktecelec.com http://www.kentelec.com ____________________ K*TEC Electronics 1111 Gillingham Sugar Land, TX 77478 -----Original Message----- From: Ken Brown [mailto:[log in to unmask]] Sent: Thursday, January 21, 1999 7:24 AM To: [log in to unmask] Subject: [TN] slot drill I AM HAVING A PROBLEM WITH DRILLING SLOTS. THE LARGER SIZE HOLES ARE NO PROBLEM BUT ANYTHING UNDER .055 IS GIVING ME CROOKED OR JAGGED LOOKING SLOTS. IN THE PAST WE ALWAYS EDITTED ARE DRILL FILES ADDING G85S', BUT A GREAT DEAL OF OUR CUSTOMERS ARE ADDING SLOTS IN GREAT NUMBERS ALL OVER THEIR BOARDS. AND ADDING G85S' BECOMES TIME CONSUMING AND LEAVES US OPEN TO OPERATOR ERROR. I REALIZE THAT FEEDS AND SPEEDS ARE PART OF THE ISSUE BUT I AM WONDERING UNDER THE SLOT DRILL CHOICE IN ROUT WHICH METHOD IS THE BEST FOR CREATING SMALL HOLE SLOTS. IT SEEMS WHETHER WE CHOOSE SEQUENTIAL, ALTERNATING, OR MIDPOINT WE ARE GETTING SOME DEFORMITY. IF YOU HAVE ANY SUGGESTIONS IT WOULD BE GREATLY APPRECIATED. THANK YOU, JIM HENDERSON COLONIAL CIRCUITS, INC. 540/752-5511 [log in to unmask] ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################ ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################ ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################