What is preferred way to panelise a Metal Core PCB (MCPCB) – V-scoring or Tab-routing?
The engineering challenge I am facing is that the boards are meant for production (1,000 qty in the initial stage) and unfortunately the most economical SMT Assembly house that I am in touch with cannot depanelise the boards for us.
So the option is either to move onto a more equipped assembler (they are twice as expensive(!)) or depanelise the PCBs on my own.
Some notes on the board design:
- It only has LEDs. No resistors or capacitors.
- The LEDs are 2.3 mm away from the board edge.
- Overall PCB thickness is 1.6 mm.
- Boards are rectangular, mostly.
- PCB is 25.5 mm x 21.25 mm.
- Panel is 5 x 8.
Considering the above, is it a better option to V-Score or Tab-route? What method will allow me to minimize board stresses?
And furthermore, what is the recommend way to depanelise a MCPCB (goal being cost-effectiveness & minimized stress on the components?)
Note: I understand that at a higher volume, I will need a better and more automated way to handle this. However, for now, I am mostly concerned about the 1,000 quantity. I am also open to the idea of redesigning the board.
An idea that I had after typing this question: I should design the panel to be tab-routed. After assembly, I could use a manual milling machine to break apart the PCBs. Will a milling machine cause stress on the components/PCB?
I have access to several milling machines and cheap labour. This is not a big issue.
Best Answer
All MCPCB panels I have seen have used a combination of routing and v-scoring (see picture). Small drills are too brittle to drill mouse bites in aluminum.
V-score must be on both sides.