PCB panelization tab routing - Page 1
Forum section: electronics / projects

author: keshab.patel
author_rank: Contributor
timestamp: May 01, 2017, 05:43:11 am
content: Hi,This is kind of beginner question. Experts please help.I am working on a pcb panel that used tab routing. So is the pcbs can be separated by the panel by hand or will require any tool.I have attached a. My designb. panel reference pic: Does PCB manufacturer makes the holes or its drilled after assembly. Does it affect panel strength during assembly if drilled during pcb manufacturing.

author: digsys
author_rank: Unknown
timestamp: May 01, 2017, 05:52:49 am
content: Routing is done at the end of PCB manufacture, and is quite stable (unless you leave too little space). You can still drill holes afterwards (if that is what you meant).I prefer VGroving, as you can get much closer groves, less messy (especially for the PCB makers), and a much cleaner edge (which you snap by hand).Either way, they are both pretty tough to accidentally snap during handling.

author: Jeroen3
author_rank: Super Contributor
timestamp: May 01, 2017, 07:58:50 am
content: I used the measures found here:https://blogs.mentor.com/tom-hausherr/blog/tag/mouse-bite/It made a solid connection with 4 of those parts over 10 cm. But the PCB fab re-framed it with their own panel with much smaller holes than my price tier. Thus: ask your pcb fab to do the paneling.

author: Niklas
author_rank: Frequent Contributor
timestamp: May 01, 2017, 10:54:51 am
content: If you are using break tabs with mouse bites, then you should also consider their locations based on the components on the PCB. This also applies to v-cut. FR4 laminate flexes a bit during the panel break up and that can cause damage to components in rigid packages, for instance resistors and ceramic capacitors in size 1206 or larger.

author: max_torque
author_rank: Super Contributor
timestamp: May 01, 2017, 11:30:00 am
content: The limitation with V-grooving is that usually, the V grooves must go from board edge to board edge, and be orthogonal to each other only (ie UP-DOWN & LEFT-RIGHT). With routing, you can have a complex slot as the router can be driven in any direction (of course you can have a zero internal radius, because there is a min tool radius)iirc, Dave did some excellent panelisation vids ages back?

author: KL27x
author_rank: Super Contributor
timestamp: May 02, 2017, 10:57:47 pm
content: I have worked with boards (other parties involved) that were a total PITA to remove from the panel. I dunno if this was because of the designer or the manufacturer. On my own designs I try to avoid really stupid shapes and just leave the tab routing and the panelization up to the manufacturer. After decades of experience, they have a pretty good feel for where and how many tabs are needed, as well as how best to manage their tooling changes for the material. In one case they took liberty of doing a really cool tab on an FPC that looks like it changed the outline a little*, but once torn out is smoother than regular tabs. The best part, you can rip the board out without any care, at all, never an exacto knife needed. This saves someone a lot of time. (I understand these particular FPC are actually laser cut, FWIW. I've seen some other manufacturers which look like they are routed.. and those tab are PITA on FPC).*For first time in years, I just now looked at this under the microscope. What looks like two little nubs on the outline is actually just extra clearance in the copper layer, so they could cut a little arrow on either end of the tab to make sure it tears cleanly, with all the stress on the outer waste nub and not the board.