Standardized drill size and minimum trace width

Layout
1

Hi,

I’m writing this to ask you some question about PCB kicad and footprint.
I’m working on my board which contain an STM32F407VG “LQFP100”, Ethernet PHY “LAN8720 /” and micro-SDcard…., I will order my board from oshpark and this is my first professional board (I made before many homemade PCBs) and I have some questions:

1/ I’m creating the through holes footprint for the crystal with HC49/US Package. In the datasheet I found that the Component foot is about 0.43(±0.125) in mm.
So when I create the footprint I put the exact same size for drill or there are a standardized size drill, and if 0.43mm drill size exist did you recommend me to put the same size or increase it a little bit to be sure that the component foot will fit in the hole.

2/ I have a question about via, the VIA in the PCB will be interconnected automatically and no need to put solder between them like I made in my homemade PCBs.
And the default via in kicad “Via 35.mils” generate automatically a VIA without hole, is that normal??

3/ in the Design rule of the manufacture Oshpark they can make a 6 mil minimum trace width, so I’m thinking making all my circuit with 6 mil except the power supply circuit 5V/3V/GND. Is that correct??? I’m worrying if that width can’t handle enough current. How can I make sure??

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  1. Always use bigger holes! I found a HC49 footprint with 0.8mm holes (sounds sensible).
  2. The via holes are not shown during layout. They should be visible in 3D mode + gerber files.
  3. Use whatever trace width you need, but not smaller than 6mil.
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thx madworm,

1/ yeah me too i found it in the kicad library with 0.8mm.

i made also the ethernet connector footprint for the J00-0045NL http://datasheet.octopart.com/J00-0065NL-Pulse-datasheet-8636335.pdf
in the datasheet page 2 they drawn the footprint and holes sizes. should i also use a bigger hole or just let them as in the datasheet.

2/ now i just tried the default via and no holes as usual, but i went to the Design Rules Editor menu / Global Design Rules and i add the diameter and drill size for Via 1, and now when i choose it from the menu and place it the hole appears.

3/ yes i think i’ll use 6mil for all tracks except the Power supply. after searching in the web i found that the 6mil can carry about 0.5 / 0.4 amps which is above of my current limit

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It might be a good idea to go slightly higher than manufacturers minimum for trace width( If your design allows that, of course). I haven’t tried myself but I have see people having problems with small tracks.