Spec-Sheet

A gun drill specification sheet can look intimidating the first time you see one. There are diameters, angles, lengths, and tolerances — and each number affects how the drill performs. I have ordered hundreds of gun drills. Here is how I read a spec sheet. Tip Diameter: The Number That Determines Hole Size The tip diameter is the most important number on the sheet. It determines the finished hole size. But the tip diameter is not exactly the hole size — there is an oversize allowance built in. ...

Machine spec sheets list dozens of numbers. Not all of them are equally important. Here’s how I read a spec sheet and what I focus on. Critical Specs These specs determine whether the machine can do the job: Drilling diameter range. The minimum and maximum diameter the machine can drill. The effective range is narrower than the spec range because tooling availability limits the actual range. Drilling depth. The maximum depth the machine can drill in one pass. This is determined by the feed axis travel and the drill tube length. ...