Damn I sorry that that happened
, Cu is
very 'grabby' even though it is soft. Try doing 1/4 turn forward then 1/8th turn back. use WD40 or 'Three in One' oil for lubricant,(we definatly used paste at school, but it was for tapping Steel). try using the tips of your fingers to turn the tap, so you can feel any increase in pressure or snags/grabs, then turn backwards and move forward/inwards very slowly in small steps/turns...
The cheap taps are VERY brittle, you get what you pay for with tools :shrug: ...
I'd go for the best ones you can afford...