Starrett Diamond Dri-Core Drills - BMC42 Dry Cutting Core Drill - For Brick Blocks Granite Masonry - 42 mm

Excellent quality and value as all their holesaws are

The picture in the Amazon listing is not of the size being sold. I was hoping for a drill bit of uniform diameter, this size 28mm is not. To take the arbor or extension, the mating end flares to a diameter larger than the hole cut by the business end. Therefore this bit cannot be used with an extension bar.It seems to get a corer of uniform diameter it must be at least 32mm.

i use it for coring out for fan ducting.

Used to core through 9 inch 7n concrete block wall. If using dry remember to clean away dust regularly as it causes the core bit to jam

I suppose the test will be after it’s been used 10 times, but unfortunately as is probably the case for most people I’ve only needed to use it once. What I can say though is it was very efficient went through a cavity red brick wall like butter. No signs of any of the teeth breaking off. I’ve boxed it back up and it’s in my workshop. I needed to do another hole for kitchen overhead extractor fan at 150mm so I’ve bought this one as well. It seems to be good enough quality and it isn’t too badly priced though don’t forget the sds adapter and be sure to church your drill has a clutch because it does grip on the way through

It took a few attempts to master this drill,I was aiming to drill a hole through a concrete brick.so for me I Drilled a pilot hole first (say 2 cm),then used this drill with a drill-bit inside (with a little force)Once the hole was 1 cm deep, then removed the inside drill bit, and just used the 1CM deep hole to guide the drill through,This gave me the best results and was very quick to do. Very happy with the hole, and position of the hole. This drill seems very solid, and I have confidence in it.

I planned to core out a hole for a flue. Fortunately, the replacement boiler also had an off centre flue so I didn’t need the drill. It did arrive on time and quality looks good. . 🤞🏿

Needed to put 2 vents through a 9 inch concrete wall. This did the job perfectly. Looks like it would do a few more easily. Don't know how it would hold up if you were using it every day. But it did what I needed it to do watch out for some of the arbours that Amazon recommends with it. Some arbours aren't straight and cause a wobble that will both make the job harder if not impossible and make your wrists ache. . If it doesn't spin without wobble on the drill you're going to have serious issues