TCT Carbide Hole Saw for Hard Metal,20mm,7/9" Tungsten Carbide Tipped Hole Cutter Set with Titanium-Plated Pilot Drill bit for Metal, Stainless Steel, Iron, Wood, Aluminium, Plastics

I needed to drill a 48mm diameter hole through 25mm thick spring steel that is already hardened. I used a milling machine and compressed air to clear the chips and heavy oil as lubricant. I used the slowest speed of 75rpm and lots of pressure. This hole saw did a really good job, the hole is clean and as smooth as can be expected. It drilled 1mm oversized, resulting in a 46mm hole. This was fine as I bought a slightly smaller cutter than the required final size. The pilot drill cut cleanly through the steel, but the cutting edge is slightly dull afterwards. The TCT brazed tips have held up very well, one has a very small chip but it will not affect its ability to cut cleanly. Extremely pleased with this very reasonably priced hole saw.

Well made tool

These are brilliant, want sure what to expect but I've had these working every day and no loss of sharpness or cutting time. I've just had to drill at a 45 degree angle and didn't snag it strip some teeth off like many holesaws would've done! Great performance for the price!

I wasn't too sure how this would work being a no brand bit. However I managed to cut 10 holes in 3mm stainless all on the mark. Taking it slow stops it jamming. The good thing about this over a spiral bit is it doesn't warp the metal and gives a cleaner cut with less burrs. The only issue I had was getting it centered. The pilot bit didn't want to stay on the hole punch. I used a stepper bit to cut a 5mm hole and then scrap wood for a guide hole. That could be an issue with my drill press.

Very good bits for the price

As others have found, the centre drill piece snapped in half within two minutes of using it. Luckily I had another drill piece that would fit but if not, I couldn't have carried out the work I bought it for without a trip to a hardware store.

To be honest I didn’t expect much due to low price so bought 2 @ 20mm. You could buy 20 of these for the price of a single WNT equivalent. I was throughly surprised by how well it performs. So far it’s drilled 88 holes in 3mm 316 stainless, 20 holes in 10mm mild steel plate & 30+ in 5mm alu check, still on the first cutter! Started with High speed for the initial pilot bit followed by low rpm for the actual hole. Kept the bit Flooded with coolant. Holes have been made using drill press or hand drill. I can’t complain for the price. It does drill around 1 mm over which if task is precise I’d recommend 1mm smaller. This didn’t bother me for the jobs I had to do. Overall cuts clean, fast and is durable across a range of materials. Real good value for money.

Great value for money. Needed to cut holes in cast iron, this certainly did the job without much effort