PCB Prototypes

Normal depanelization method is shearing with aid of CCD vision system. This allows for cutout with precision tolerance of +/- 10 mils. Depanelization by shearing is limited to rectangular as the cut has to be straight and of right angle. For more complex cutout requirement, we will be using CNC routing. This allows for

1. Custom Shaped Board with internal cutout shown	2. Tab -routed panel without frame

Oversized holes, exceeding 0.200" would also be CNC routed as internal cutouts. Because CNC routing requires extensive preparation, a surcharge of USD 20.00 is applicable for the setup. The cost for depanelizing each board remains the same as normal depanelizaton.

Additional Consideration When Designing For CNC Routing

1. Angle Limitations

The standard router tool used has a 0.060" diameter . Please take into account that any right angle would be rounded by a 30mil radius turn.

2. Minimum Router Diameter

The design for internal cutouts or routing should take into account that the tool size is 0.060" . So specifying an internal cutout smaller than 0.060" in width or length should be avoided.

3. Smaller Router Tool

Though normally we use a 0.060" router, we also keep 0.032" diameter router tool in our inventory. As it is very fragile, we only use when it is absolutely necessary, such as slots of DC jack connectors. If you have internal cutout/slot requirement for the use of 0.032" router bit, please state so during order or quotation request in the "special request" section.

4. Smallest board possible

With standard depanelizing rates, the minimum board size is 0.5"x0.5". Any smaller than that would be very hard for us to handle. We have made boards as small as 0.25"x0.25" but additional surcharge is applicable as handling this small pieces is painfully slow using tweezers.

Questions about CNC Routing

How precise is the cutout?

+/-1 mil for the board size. +/- 5 mils for the cutting alignment.

When I draw the outlines for the cutout do I need to compensate for the routing bit diameter?

This is not required. Our Gerber CAM software will do the necessary calculation to compensate for the routing path of our tool. Simply specify the board outline exactly as you would expect it to be routed out.

Is there any shape you cannot route out ?

While there is not real limit in the shape can cut with CNC routing option. we are limited by the 0.060" diameter of the tool. To test whether your specified shape can be cut out satisfactory. Do this

1. Print out the board outline onto a sheet of paper.

2. Use a thick permanent marker and trace around the outline (simulating a 0.060" router bit)

If you can easily trace a thick marker tip around the outline without running into the outline boundary then there shouldn't be a problem routing out the specified outline.