i had some issues when writing the instructions for assembly. Mostly, I didn't really think about how to explain it to someone else. writing them was actually helpful in finding some of the would be design flaws before manufacturing. Although more than likely i would catch them during manufacturing and forget to update the design. i have found that my cad skills are not always up to scratch and am a bit of a neophyte when it comes to electronics, but my machine shop experience has been enough for now.