BINOTA Concrete Hole Saw 100 mm, Arbor SDS MAX 220mm, for Masonry Cement Wall Brick Sands Stone Sable-Rock Self-Leveling

I needed a tool for drilling holes in 8" thick poured concrete basement walls for installing a radon system. After searching a number of products and checking reviews, I picked this set as it offered several hole sizes and 2 drive shafts (SDS and SDS Max). I opted to run the 65mm hole cutter based on the size pipe I was running, and wanted to start with smaller hole and only go larger if needed. For the drill motor, I used a HF Bauer 1641E-B SDS rotary hammer.I started the hole using water to flush the dust out of the hole, but this made a sticky sludge that coated the cutting teeth, made a bit of a mess, and slowed down the process. I only ran the drill at about mid speed, so the cutter never got more than a little warm. I cleaned the hole and ran the cutter dry from then on, using a utility vac to keep the debris evacuated. This sped up the process. Overall, it took me about 3 hours to go the 8-9" thru the wall. Again, this was some pretty solid concrete. The cutter never stalled, but it was a slow, steady process. The resulting hole was a little oversize (approx 70cm) but this was reasonable. You will have to stop every so often to chisel out the center concrete as the cutter only cuts the perimeter of the hole. This is the case with any cutter of this depth. The cutter length with the shaft length was plenty to cut the 8-9" thru the concrete wall with a little depth to spare.I had to drill a second location wall hole a few weeks later. As before, I scanned the wall with a metal detector to avoid hitting any rebar. I ran this hole dry, same mid-range RPM, and evacuating with a vac. Only took about 2 hours this time, same wall thickness. After finishing the hole, I inspected the cutter and noticed a couple of the teeth had broken off. Not sure when this happened as the cutter performed consistently and never seemed to slow down. Hole was very clean, no rebar contacted.Since I didn't need a whole new set, I contacted the vendor and explained the nature of the drilling, and asked if I could buy just the 65mm cutter. They very graciously sent me a new cutter and SDS shank (at no charge), which then got lost in shipment. When the vendor found out, they sent another cutter and expedited at their own expense. This is exceptional customer service.Finally, for those considering this set- I used it on a vertical poured concrete basement wall. It is difficult and slow, no matter what cutter you are using. This tool would be faster in hollow cement block, or drilling thru a slab. In any type of poured concrete drilling, do yourself a favor and use a metal detector to avoid hitting any rebar. I am a mechanical engineer and know how to get the most performance from the tools I buy, and I was impressed with this set, even though I knew the job would be a challenge.I'm not easily impressed, but this product and especially the vendor impressed me a great deal. I will definitely buy from them again. My reason for leaving such a detailed review is that it was a struggle finding adequate information about these cutters when I was searching. Finally, this set also includes an SDS Max shank as well as the SDS shank I used. Both are approximately the same length.

Used this today... Worked very well...

Works well but Ill need to use some loctite on the set screw for pilot bit. Constantly backs off and being an Allen key screw, it naturally is wearing the quality of the insert

The key to cutting concrete with such a large bore is to:1) Cut small relief drill holes around circumference2) Use dripping hose to keep cool with water3) Use rock chisel to break up center bore core every inch to lessen fiction

Good for the price but used the 3-1/8 bit on an 8" wall and 90% of the carbide teeth have came out. Also the pilot bit constantly vibrated loose.

Me dio muy buen rendimiento, para los que queremos hacer un trabajo limpio, y tienes el taladro adecuado, que puedas usar con esta broca.

Chisel worked a lot faster than this bit. Tooth on Thai bit were dull in matter of minutes.

Update: I have now cut through at least 120" of concrete with this set cumulatively. The cutter head had held up very well. The only part that is not well designed is the drill bit getting loose often. For the price, it is absolutely worth it.Original review.They lasted well I think. I have cut a good number of holes in our 12” foundation wall with the smallest bit and it is still holding up and teeth are intact. I’m happy with how the durability.The only down side is that the screw holding the drill bit undoes itself frequently. Not a dealbreaker to me.

The set screw that hold the bit in extends past the body of the hole saw which only allows the bit to go into the wall as far as the set screw. Makes the long extension useless.

bon produit, il a fait le travail Good

Me parece de muy buena calidad

Ça marche bien même s’il faut le temps dans la brique...Dommage que ce soit un peu trop court pour traverser une façade de part en part, il faut au moins 30cm.

producto bien probado en hormigón cumple su función correctamente, totalmente recomendado