UK Drills HSS Step Drill Bits Set Titanium Coated 3pc 3-20mm for Drilling on Hard Metal, Stainless Steel, Cast Iron

Excellent drill bit and works well drilling steel channel which I needed to feed micro tubing through. Good value and quality

Why did you choose this product over others?:Did the job well

Value for money, quality and what I was looking for

I had a relatively small job to do and fit new rear lights on a horse box, old lights not available anymore so I had to re drill the trailer and also needed was drilled stainless steel plate.. for the money they went through the galvanised steel like butter but not so good on the stainless but did the job and not a £100. very pleased.

Decided to replace some the tuners on an old guitar, but the old tuners were an 8mm hole fit, and in general modern tuners require a 10mm hole, so needed a way to increase the hole size. After doing a bit of research on the best way to do this, it looked like what I needed was some stepped drill bits that went from 8mm to 10mm, and these looked to fit the bill. Tried on one hole with the 2mm stepped bit to test, and this increased the whole very easily and neatly, but as the length of the steps are less than 1/2 the thickness of the headstock even after drilling out from both sides of the hole this I was still left with a 1 or 2mm deep ring that was still 8mm in diameter. I initially tried to clean this out with a round file, but the tuners were still a bit too tight on some of the holes, so I re-drilled the holes out, this time going in with the 11mm step bit. I did this from both sides again, but in hindsight it would have been better to stick with the 10mm on the back, and go in with the 11mm step from the front only. Alternatively a 10mm regular drill bit would probably get rid of the inside ring without having to drill either side out to 11mm. I will try that on my next guitar. As it was I was then able to fit the new tuners fine, and it looks a really neat job.You may be wondering why I didn't just use a 10mm drill bit to begin with, but this doesn't work very well as it chews up the edges of the hole and can drift off centre.You might also be wondering why I gave these bits 5 stars, and not 4 because the steps aren't quite long enough. Well it looked to me like all step drills have this limitation, so these seem about as close to perfect as you could get for what I wanted to do, so 5 stars it is.

Great does exactly what it’s supposed to

Ok but not for chomping through any hard steel. The smaller one broke almost instantly. But you get what you pay for I guess

Would not cut through 3mm box section I was making a set of clamps for woodworking I drilled a 13mm hole to take the threaded bar but I needed the top box section to slide up and down so I thought I could increase the size of the hole with this tool but sadly it was not to be had to use the angle grinder to lessen to thickness when the box section was about 1mm it cut through