How to de-panelize odd shaped PCB? - Page 1
Forum section: electronics / general

author: Faringdon
author_rank: Super Contributor
timestamp: November 07, 2022, 09:03:24 pm
content: Hi,If your PCB is the shape as attached.....200W PFC with full bridge SMPS, how do you depanelize it and assure you dont flex the board with the MLCC's and SMD res on it etc?

author: Warhawk
author_rank: Frequent Contributor
timestamp: November 07, 2022, 09:07:10 pm
content: I assume there are no mousebites, right?What about drilling a 2mm hole one next to another and then cracking it in half?

author: Faringdon
author_rank: Super Contributor
timestamp: November 07, 2022, 09:40:20 pm
content: Thanks, i hope my diagram is not misleading,.... thats one PCB, in a kind of long headed T shape.

author: SMTech
author_rank: Frequent Contributor
timestamp: November 08, 2022, 08:49:22 am
content: Quote from: Warhawk on November 07, 2022, 09:07:10 pmSurely there are mouse-bites? In which case you can buy a handheld tool that nibbles them outhttps://grovesales.co.uk/hand-tools/depaneling-tools/I'd avoid the black "G-tek" ones tho' they're quite blatantly the same no name tat you can buy on eBay for £10, the finish isn't very nice and they can scuff the resist layer. Very odd shapes can mean a lot of mouse bites and quite fiddly work.I think the risk of damage from bending is overstated, unless you're extremely ham fisted you should be able to break V-score with minimal flex and bites with basically none.Straight lines with v-score can utilize guillotine cuttershttps://grovesales.co.uk/pcb-depanelizer-ges460/.At scale, and where stress or tidiness matters you have router de-panelisers these can use standard routing or laser, both of those involve dust and fumes and all that goes with that so are less common.

author: AndyBeez
author_rank: Frequent Contributor
timestamp: November 08, 2022, 09:17:28 am
content: You panelize to a rectangle. In this case, each panel is 210x100mm.The T can be done by milling slots along the 8 and 5cm edges, which can be snapped. That's a lot of waste PCB. Think about using the area of the two 80x50mm pieces for some other circuit? The Fab house will still charge you for the waisted 80 square cms.Or make the 50x50mm square continuous with the 160x50mm piece, snap this, and bridge the two parts with wire or a pcb edge connector to make your T? Might work out cheaper in parts than in waisted area?

author: wraper
author_rank: Unknown
timestamp: November 08, 2022, 10:15:24 am
content: Do you panelize like this to maximize production costs?

author: Matt-Brown
author_rank: Regular Contributor
timestamp: November 10, 2022, 08:37:45 pm
content: Most board houses will panel for you. Ask for v-score only and give them a max size of array you can handle/process. mopst laminate is 18x24 inches or 18x12 inches. I prefer to keep to around 8 inches by 11 for my arrays, just for machine processing.board houses will also let you know if they need to route/ mouse bite

author: Infraviolet
author_rank: Super Contributor
timestamp: November 12, 2022, 06:34:13 pm
content: Where are you getting the PCBs made, most manufacturers will, even for batches of many PCBs, depanelise for you at their end.If you do get a PCB attached to a panel, my advice for removal would be to use a "sharp D" profiled needle file (flat on one side, curve on the other, fairly sharp edges at the top and bottom of this D shape) as you would a hacksaw, using a file instead as you can be a bit more delicate filing with the sharp edge than you can sawing by hacksaw. This will get through PCB material pretty quickly and give a clean edge without causing any violent stresses elsewhere on the board. Make sure the board id designed so there is no copper of any layer close to the area you are filing through, as filing in to a copper area could cause tears which could spread elsewhere on the board.