Recently I've been working on maxing out the efficiency of my machine and I've come to some very interesting conclusions.
1. Never cut above 75%. I've even heard arguments to never go above 65% as you did as you're not getting that much extra power but you are wearing out your machine significantly faster.
2. With machines up to 100 W there is no point cutting above 175 mm/s. for the most part you don't want to go that fast anyways because the quality is terrible due to the high-speed. I found on my own machine that anything above that basically produced almost no gains.
3. Most machines won't fire below fourteen 14%.
4. don't engrave above 350 mm/s as the results are very bad.