OCGIG 4pcs Chamfer Countersink Deburring Drill Bit Set HSS 4241 Crosshole Cutting Wool Metal Plastic Tool

The tool finish shows signs of economy with burrs on the thru hole bores, and clearly marginal Ti n coating. However, performance is superb on my need for countersinking 316 Stainless steel neatly. With quality cutting fluids the cutting edge gets under the surface with continuous swarf peeling off. Chatter free and fast, very happy.

Wish I'd found this tool many years ago as it's so much better than a standard counter-sink. The cut is clean and perfectly circular unlike the wobbly outline countersink you normally get. There is also very little vibration from the countersink bit which allows you to get accurate centres and depth to the hole.

Best type of countersink Tried yet, cleanest counter sinks Iv drilled. But does go blunt’ish soon enough. But for price can afford to replace them every now and then. A worth while addition to the tool kit.

These work beautifully on plywood. No tearing nor juddering giving a perfect countersink.Hardwood is the same. Used a few times on aluminium and also gave great results but it was the plywood that they were bought for mainly.

They work ok in plastics , , nylon , wood and at a push aluminium. For harder metals they performed poorly. If you want something to use in a machine shop or metalworking then save your money and put it toward a better made product.

For years I have had problems countersinking concentric to the main hole. It drives me crazy and looks very amateur on the finished piece. The marks left by traditional countersink bits from the chatter also look very second rate. These bits largely address both problems. And if you are really fussy (like I am) about the countersink being concentric to the hole, you can even start by countersinking and then use a hinge bit to put the main hole directly in the bull's eye. Starting a traditional countersink bit in a piece of wood or metal without at least a pilot hole is almost impossible (in my experience).

Superb performers. After all the years of faffing around with larger drills to countersink, these are excellent and good value for money for my private woodworking.Recommended.Thank you.

I’d not seen this design of countersunk bit before. They work just as they should do.