trouble is at 50/1 theres very little room for error ,,, at 35/1 you can be a bit off and it makes no odds , 50/1 is a recent thing , old stuff like seagulls ran at 25/1 granted oil wasnt as good , in fact they used engine oil for two stroke as did many bikes of that era.Manufacturers say 50:1, or on cheaper tools, 40:1. The more oil you use, the more it will soot up and give other issues.
I've had some of my tools apart and even at 50:1 theres a good thick oil film where it matters.
I have a small measuring beaker, 60ml oil for 3L of petrol, is my usual mix.