drill bit

Accurately Drilling a Hole

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dti brackets cut and drilled

Accurately drilling a hole can be a challenge even in a milling machine with all axes locked, apart from the quill movement. I start with a centre drill. The centre drill is short and so it doesn’t wander around the mark. Drill gently to ensure that the centre is perfectly aligned and drill into the … Read more

Pinvice

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pinvice held in hand

I have a number of small pinvices, but they tend to be rather crude and not very accurate. I also have a larger hand drill that is literally a small chuck attached to a steel shaft that has then been driven into an old file handle. This is very useful in the toolbox, but far … Read more

Twist Drill Basics

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the model engineer and electrician magazine logo

The twist drill basics introduces the angles, clearances and how to get a drill to run straight. There are a number of different forms of twist drill, different base metals, different coatings and an even larger array of ways in which you should sharpen your drill bits. This article has been abbreviated from the 20 … Read more