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Removing tabs/burrs/ from manufactured PCBs.
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Please be positive and constructive with your questions and comments.

Removing tabs/burrs/ from manufactured PCBs.

by ScottDWebster on Wed Apr 17, 2019 9:04 am

I recently received my first PCB order from OSH Park (not my design) and the tabs that had held the various boards together (they are cut almost apart leaving small tabs to hold everything in place until they are broken apart later) were left on the edges of the PCBs.

I was wondering how people who have ordered PCBs like that have dealt with removing those tabs. I used my Dremel with a cylindrical grinding stone to grind them down and smooth any sharp edges but didn't get the edges completely flat. I was a little afraid of going too far and leaving concave divots in the edges. I may buy some high grit sandpaper to attempt to get the edges completely flat where some bumps remain.

Any other suggestions?

ScottDWebster
 
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Re: Removing tabs/burrs/ from manufactured PCBs.

by adafruit_support_mike on Thu Apr 18, 2019 1:52 am

I generally use an old, coarse file to take off the biggest pieces.

FR4 is basically fiberglass, and the glass chews up cutting tools. Even carbide drills get dull faster when you drill PCBs. It plays havoc with the sharp edges of a new file, but an older file will have rounded over a little, making it a bit more durable.

You can also use sandpaper with a hard backer. That tends to be slower though, and there's more chance for uneven grinding.

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Re: Removing tabs/burrs/ from manufactured PCBs.

by adafruit_support_bill on Thu Apr 18, 2019 5:52 am

A file is my preferred tool as well. For straight-sided boards, an edge-tuning tool for skis holds the file at the right angle so you get nice clean square edges.

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Re: Removing tabs/burrs/ from manufactured PCBs.

by ScottDWebster on Wed Apr 24, 2019 1:58 pm

OK, thanks for the suggestions. The grinding wheel on my Dremel worked fairly well for removing most of the material. I bought some 400 grit sandpaper (I was originally thinking of using 1000 grit but decided that would be overkill) to finish off the smoothing of the remaining bumps. I held the sandpaper flat on the table and rubbed the PCBs over it. Next time I think I would start with 220 grit sandpaper to flatten the bumps first and finish off with the 400 for a smooth finish.

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Joined: Sat May 06, 2017 7:02 pm

Please be positive and constructive with your questions and comments.