Chiloskit Large Step Drill Bit, High Speed Steel Unibit Step Drilling Bit Set for Metal Hole Cuter Wood Hole,4-52mm

This thing ripped through 1/8 inch metal no problem.

I like the fact these bits "self-center" in an existing hole. The limitation is they will not work on materials that are much thicker than 1/8"., because the steps are not much thicker than that. Big chunk of metal for not a lot of money. "Titanium" means the bit has a very thin layer of Titanium Nitride coating it. The coating lubricates a little, helps prevent rust, and is harder than the metal the tool is made of. In practice the hardness of the metal, the tool is made of, is more important than the thin coating. I am almost certain this was made using "hot isostatic pressing and sintering of powdered metal". That means a little harder than mild steel, but not as hard as heat treated tool steel. Price is right for occasional use.

I was needing a huge bit to bore a hole in the dashboard for my 1941 Chevy Pickup restoration. Since the windshield wasn't original, I turned the spot for the window crank into a mounting spot to put a uncirculated 1941 silver half dollar.Anyway, this big dog definitely did the job it was required to do. Only wish my drill press had some more power. Bit kept freezing up during the turns but it still did it's job flawlessly.

It's 52mm and it's great. I just couldn't use it for what I needed. However, it can clearly cut. It's easy to get a hole started even without a center punch. Definitely recommended.

It enlarged two existing holes in a tool chest big enough to install grommets and pass power cords through. It did as intended.However, the backside of each new hole was not cut clean; the end result mimicked Friction Drilling, leaving behind nearly enough material to thread with a tap. Simple fix with a grinder.Uncertain if the step-drill is to blame or my own feed-speed, as this is the largest of many step-drills I’ve used.Job is done, tool did not break. Meh, it works.

I used this bit to make a 1 3/4" hole in my patio table 2" so a larger umbrella would fit. Used WD40 for lubrication and it worked like a charm. Not sure how many more holes I could drill with it, but it worked for one!

For the cost, it's fine. Cheaper then the machine shop. Was able to get 4x 40mm holes drilled out in 1/8" steel no problem but performance degraded over time. There was noticeable wear and tear afterwards.

Good value for money inferior products, total waste. Like a (optimistic) idiot, I threw it in the box that I put it in by mistake. In any case, don't waste your money.