![]() ![]() unplated mounting holes means no visit to the mill prior to plating so you save a production step (unless you have plated slots in the board in which case it doesn't matter at all) so, maky your life simple and simply place a pad with pad diameter and drill diameter set to the same value and 'plated' unchecked. milling plated holes means the board needs to visit two machines prior to plating.and the mill to do contour routing. if you set mounting holes to unplated they simply get milled during board contour milling so you incur no additional processing step on the drill ( board fabs use different machines for drilling and for milling. Almost nobody drills larger than 2mm : they switch to router bits as these have a longer lifespan. These tools do this conversion in one shot. all the boardhouses these days use either Ucamco or Genesys Frontline as data intake software. since the size is larger than 2mm it will be automatically converted to a milling step. They will detect unplated holes in the Gerber data and automatically convert these to post plate step. NON-ISSUE place a pad with pad diameter and hole diameter set to 2.4mm. Is that true? I am offering ten(10) engineer-nice-person points for an elegant solution to this trivial problem! cheers Place a primitive/polygon on a mechanical layer and perform TOOLS>CONVERT>CREATE BOARD CUTOUT FROM SELECTED PRIMITIVES problems: -there is no nice screw model representation like in METHOD 2 -will it generate proper gerber drill data to the manufacturer? I am afraid it will be just a random cutout that they will have to route in some expensive way -I don't get the nice dimension outlines: screw head (grey circle) and screw clearance (green circle) -it will not make a plated hole: I have read that its best to keep all holes plated, even mounting ones, as it reduces the tooling overhead. problems: -this METHOD gives errors when processing the PCB as it is an object in the PCB not referenced in the schematic -I also tried creating a schematic library part, and adding the above mentioned PCB library footprint(pad) and 3D model to it - now I had to hide unnecessary bloat items in the schematic -same Eurocircuits fabricator problem as above METHOD 3. You could add a 3D model to each screw hole in the METHOD 1, but you would have to align it one by one, and here its all pre-done. The bonus is that you can add a 3d model of the screw, which makes it much nicer for the final board 3D render. Create a PCB library footprint for the hole (also from a pad). What gives? How do I make a larger hole then? METHOD 2. Clearly that can not include routing and cutouts. problems: -if you set annular ring to 0mm you will get manufacturer errors, as you will get a virtual 0mm point surrounded by soldermask clearance ring in gerber files -if you set annular ring to 2.4mm, same as hole size, you will get a hole with soldermask clearance ring (makes the soldermask susceptible to peeling with screw torque) -using a PCB template rules from (my fabricator of choice) for Class 6C - 2 layer - 1.55 mm i get an design rule error saying "Hole Size Constraint (Min=0.25mm) (Max=2mm) (All) 4" which means they do holes up to 2mm. Place a pad on the PCB, set hole size to 2.4mm and annular ring size to less than 2.4mm. I have found three methods used to make mounting holes, none of them is satisfying to me: METHOD 1. I want to make a mounting hole of 2.4 mm diameter for a M2 screw. ![]()
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