Review on 🔩 IRWIN 91140 8 Inch Silver Deming: Premium Quality Industrial Drill Bit with Precision and Power by Ben Demers

Stays sharp, cuts through the cast iron chain mount on my Jeep TJ frame. My wife dripped a few drops of oil on it about every minute and I drilled slowly and carefully. (The drill bit in my Makita LXT211 combo kit has two speed settings. One for 0-400 RPM and one for 0-1500 RPM. I ran it on low speed about halfway through, which felt a bit too gentle Eventually I stopped on the trigger, cranked it up to 400rpm and used medium pressure with a few drops of oil about every 30 seconds Works well with my hand drill, it never got out of control and never surprised me except once it got stuck at the very end .) The expansion hole came out very clean. The punch was undamaged and felt just as sharp as it had started. Irwin is one of the last American manufacturers of decent drills that are readily available and reasonably priced. There are better ones, but they are hard to find and very expensive. For the DIY market and occasional heavy use, this is a great drill bit.