SMD Assembly

Project SMD Assembly
Status	In progress
Contact	f0x
Last Update	2020-03-10

Assembling your own SMD stuff isn't that hard :) This page is a document-as-we-do-things(-or-afterwards) log

Stencil

You can either order this with your board, or lasercut these yourself from Mylar. JLC has really cheap stencils, at ~6 euros for 380x280mm you can either order with your (panelized) boards, or separately afterwards Lasercutting works well with engraving at speed 50, power 5, 0.02mm spacing, but is really slow (and thus quickly more expensive than JLC). For some pads you might want to shrink them down to 90% size, but for the 0805/sot23/soic/tssop stuff I did 100% was fine.

Applying Paste

noopwafel has a 500g(!) tub of (lead-free) Loctite GC-10 T3 lead-free paste, and a paint scraper for applying it. Feel free to use some, but please don't contaminate either (ask for help if needed). It is stable at room temperature and remains sticky for several hours.

Components

There are SAMLA's of sorted and unsorted SMD components above the soldering table. Our selection is a bit random/limited right now. LCSC and TME seem to be the cheapest places for components.

Pick-and-Place

The silver 'gatenkaas'-tweezers are alright, but I prefer reverse-tweezers with ceramic tips (cheap on aliexpress). Interactive HTML BOM is an amazing KiCad plugin that exports a single html webapp that, well, shows your BOM interactively, and where to place everything on the board. You can see a demo page here LiPo Module Interactive BOM

Reflow

We have a Reflow Oven, be careful with your temperatures as I burnt my first panel, a Hotair rework station, and a Preheater.