Here are the charts I have made so far for BSW, BA, ISO and ISO fine.
They all give a choice of drill size depending on what thread engagement you want. The ranges covered are 65% to 85%. I've also added clearance size drills to some of the charts too.
Most of this info I got from the workshop series book and drilling an tapping which is an excellent resource and better still not expensive.
I still need to do one for BSF
View attachment BSW Chart.xls
View attachment ISO tapping Chart.xls
View attachment tapping BA.xls
They all give a choice of drill size depending on what thread engagement you want. The ranges covered are 65% to 85%. I've also added clearance size drills to some of the charts too.
Most of this info I got from the workshop series book and drilling an tapping which is an excellent resource and better still not expensive.
I still need to do one for BSF
View attachment BSW Chart.xls
View attachment ISO tapping Chart.xls
View attachment tapping BA.xls
