Customer Reviews

Irwin Industrial Tools 10228 Unibit 228 Step Drill Bit Set 4-Piece

5 star:		(2)
4 star:		(0)
3 star:		(0)
2 star:		(0)
1 star:		(2)

 

 

I haven't used these in ferrous metals, but they are indispensable for drilling and countersinking in brass and aluminum. Twist drills often grab in softer metals, leaving an out-of-round hole. These bits drill smoothly and accurately, and countersinking is a simple operation, too. Highly recommended for brass and aluminum fabrication.

I have used these for years, but the current production is of inferior steel. Very soft and does not cut well at all. Suitable only for soft metals. Irwin seems to have outsourced the production to the lowest bidder.

I have used the #3 to enlarge 15 holes in a 1mm thick carbon steel box.
I didn't know if it would stand for that job but it was amazing how easily it cut the steel.
No scratches on the bit, excellent finishing.
If you need it, don't hesitate to have yours.

$63 for four drill bits, however specialized, is ridiculous. That comes out to $15.75 each! When this company, Irwin, goes out of business and has to sell their patents then maybe the next company to manufacture these type of bits will sell them at a reasonable price.