Imo engi is way too random. If Wiki is right, its 1-50% chance to get a point.
I listened to the guy here saying craft magneto laser pistols. I crafted 35 laser pistols, then 35 Magnetos. 1 Engi point. ONE.
After that I spent ressources of at least 2 days of scavenging I horded, crafting all kind of stuff, armors, weapons etc. Another 2 points for like 1000 scraps/metal/etc.
There just has to be some easier way, cant imagine how people reached 200 or even 300 without some kind of abuse. Someone told me Sharpened Poles is the way to go (2 wood for 1), but after creating about 200 poles, all I got is some science points.