I wanted a solder paste stencil to make it quick and easy to reflow emitters onto Noctigon 4XP 33mm MCPCB used in the Emisar D4S flashlight. I made a gerber file that I used to cut a stencil out of polyester sheet using a craft vinyl cutter.
Most flashlight hobbyists don’t bother using a solder paste stencil when reflowing emitters. They just slop some solder paste onto the MCPCB thin it out a bit, put the emitter on and then heat the MCPCB until the solder paste melts. Then they wiggle the emitter around to make sure the solder is evenly distributed. Finally, they give the emitter a “bonk” to eject excess solder and let it cool.
I’ve used the slop & bonk method before with decent results, but its a little to fussy and inconsistent for my tastes. It’s workable for single emitter boards, but with triples and quads, trying to manage the inconsistency leads to more fussiness which leads to the emitters being heated longer, which can reduce their efficacy.
Solder paste stencils reduce variability and fussiness. They make it easy to apply a precise amount of paste evenly, which makes it practical to reflow emitters with little or no manipulation during the molten solder phase.
I’m sharing the gerber file in case anyone else has access to a suitable cutting plotter and wants to make their own. I used the open source Gerber2Graphtec software to convert the gerber into a file that I can send to Silhouette Cameo 2 cutter. This software only works with Graphtec-based plotters, like the Silhouette family.