Pinning a Board
The alignment of your circuit board is determined by the precision of the pinning holes. For example, if there is a 0.05mm (0.002”) play in your pinning holes, then the boards position while drilling and milling the component side may have up to a 0.05mm (0.002”) variance. In addition, when you flip your board over to mill your solder side, positioning may also vary by 0.05mm (0.002”). This results in a potential variance of 0.10mm (0.004”). It is of the utmost importance to create pinning holes as precisely as possible. Typically, a tight pin will have no positioning variance. After making your board, the bottom side should align perfectly. If it does not, see “Set Home Position”.
Drilling Pinning Holes Using the QCJ5
Place a piece of back up on your Quick Circuit. Place a piece of board material over the back up. Load the file “Tooling Holes”. Run the drill layer. The software will prompt you to load a 1/8” drill bit if there isn’t one in the Tool Pod. Set the speed to 50,000 RPM, Feed to 20 inches/minute and the depth of cut to 90 mils.
Drilling Pinning Holes Manually Using the QCJ5
Load a 1/8-inch drill into the spindle. Jog machine over one of the 3/16 inch holes located at the front and back of the Pinning Grooves on the table top. Turn spindle on, use an RPM of 50,000. Place backup and work piece on the table top so that the drill bit is directly over one of the marked hole locations. Secure material to table top using masking tape, and jog Z-Axis down and up through both materials. Place a pin in the new hole, and drill second marked hole location.
Drilling Pinning Using a Drill Press
In order to maintain accuracy, the backup material is pinned to the circuit board material. The backup material should cover and protect the entire area beneath the circuit board material. Use a drill press to drill the holes simultaneously through the backup material and the board material for the dowel pins. Drill your 1st pinning hole through the board and back up material. Place a dowel pin in the hole. Then, drill your second pinning hole. By leaving the first dowel pin in the board and back up when drilling the second pinning hole the pins will fit tight and secure.
Vacuum Array Board Material: Load file BM-BACKUP-2H provided with the IsoPro software. Secure new work piece on top of a piece of backup material using masking tape. Select desired pinning holes, and mill selected using IsoPro.
Drilling Through-Holes Using a Drill Press
Step 1: Drill through the backup material and board material at location A. (Drilling through the backup material first helps ensure precision locator holes.)
It is good practice (but is not required) to drill the pinning holes on the center line of the board material approximately 16 mm (5/8”) from the edge of the board.
The exact positioning of these holes is not critical. What is important is that the holes are drilled cleanly so that the dowel pins fit tightly into the holes. Holding the board and backup material firmly while drill-ing will help to ensure precision locator holes. Taping the board and backup material together at the corners before drilling allows easier handling of the materials.
Step 2: Pin the board and backup material together with a dowel pin.
Step 3: Turn the board material around and drill through the backup and board material at location B.
Step 4: Pin the board and backup material together at hole B with a dowel pin. Have the dowel pins flush with the board side and protruding through the backup material.
Drilling Through-Holes Using QCJ5
If you do not have a drill press, it is also possible to use the QCJ5 to drill the pin holes. The QCJ5 has six (6) drilling clearance holes located at 4” (101.6 mm), 5”(127 mm), 8” (203.2 mm), 9”(228.6 mm), 11” (279.4 mm), and12”(304.8 mm) from the primary pinning hole. Refer to figure 7.
Step 1: Double-click on the IsoPro icon on your desktop.
Step 2: Initialize the QCJ5. (Make sure to adjust the Air Gap, Up Force, and Down Force air pressures)
Step 3: The first drilling clearance hole is located at approximately 3,687 mils (93.7 mm) from the home position along the X-axis. This should be verified in order to prevent accidental drilling into the table top. Select Mill > Move from the menu bar or by pressing Ctrl+M. Enter 3,687 mils (or 93.7 for mm) into the X field, 0 in the Y field, and 0 in the Z field. Also, select the “Relative” option and click “OK”. The machine will move to the specified location. Make sure the spindle assembly’s collet has centered itself above the drilling clearance hole.
Step 4: Insert a 125 mil Drill into the spindle: If you have a 125 mil drill bit in the Tool Pod, go to the Tool Table (press F4), locate the tool in the “Tool Pod” section. Right click on the desired tool and select “Get Tool”. After the machine has moved back to the drilling clearance hole position, select “OK” to close the Tool Table dialogue.
If you do not have a 125 mil drill bit in the Tool Pod, you can load a tool manually by selecting Mill > Tool Change from the menu bar. The machine will move to the manual tool change position. Open the collet, insert the drill bit in the collet until the ring rests on the collet, then close the collet. Select “OK” to return to previous position.
Step 5: While the tool is centered above the drilling clearance hole, place the board and backup material on the table in the correct position to drill pin hole A. Put it upside down, so to speak.
It is good practice (but is not required) to drill the pinning holes on the center line of the board material approximately 5/8” (15.8 mm) from the edge of the board.
The exact positioning of the holes in the board is not critical. What is important is that the holes be drilled cleanly so that the dowel pins fit tightly into the holes. Hold the board and backup material firmly while drilling helps to ensure precision locator holes. Taping the board and backup material together at the corners before drilling allows easier handling of the materials.
Step 6: Open the Machine Jog dialogue (ctrl + j).
Step 7: Turn on the spindle by pressing the “Spindle On” button.
Step 8: Lower the tool by pressing the Z-Axis down arrow. Lower the until it drills through both pieces of board material the press the Z-Axis up arrow to raise the tool up out of the material. Turn off the spindle by pressing the “Spindle Off” button.
Step 9: Pin the board and backup material together using a 1/8” dowel pin.
Step 10: Turn the board material around and repeat steps 5-9 to drill through the backup and board material at location B.
Pinning Boards For ContactByTouch
NOTE: The copper on the board material must be isolated from the rest of the machine for Contact By Touch to function properly.
Methods for isolating the work piece from the rest of the machine: Deburring method (required): Use a deburring tool to remove the copper from around the hole to create space between the conductive board material and the conductive dowel pin. ContactByTouch will not function correctly if this procedure is not performed. Non Conductive dowel pinning Us a non-conductive dowel pin to secure the material and back up material to the table top. dowel pin trimming: Trimming the pins so that they do not contact the top side of the board material (This will not work for thru-hole plated boards)
Vacuum table utilization: Place board material on top of vacuum array backup material and pin them together with a dowel pin. Activate vacuum table. When you are ready to start making a board, place the pinned board and backup material on the milling table with one of the extended dowel pins in the primary pinning hole and the second pin in the groove that runs down the middle of the milling table. Have the board material facing up.