Drill America DWT54455 1/4-20 UNC High Speed Steel Bottoming Tap, (Pack of 1)

Worked great

I have bought and used a lot of DA HSS taps and have had good luck with them and I am hoping this is a one off on the one I just got. I was tapping a blind hole in a piece of brass and had already tapped the hole with a plug tap and then planned to use the DA bottoming tap to finish it off, as soon as the tap started to get resistance to finish off the last couple of threads is snapped like a dry twig, this was in a lathe and using a spring guide to keep it straight so there was no side load and all done by hand power. Im giving it a three star rating just because of my past experiences with DA taps and hoping that I dont run into this again.

I had an antique made of cast iron and had several crusted shut or heavily rusted bolt holes. I bought this tap in the 1/2-12 size. It opened, chased and rethreaded all the holes without skipping a beat. I locked the tap in a pair of Vise Grip pliers and turned slowly. It cut right through the rust first pass and brought those 80 year old bolt holes back to life. I was really impressed with the quality of the tap for the price.