Using Greenlee Punches

Greenlee punches, also known as knock out punchers, slug busters, chassis punches, Q-maxes or panel punches. They are, simply put, a type of hand tool used to punch holes in a sheet metal. The Greenlee punch is a very simple tool in how it consists of three basic components – the punch (i.e. the part which makes the holes), the die (i.e. the part which shapes the sheet metal) and the screw (i.e. the part that is fastened into the hole). 

Whilst they have many different names and types, fundamentally, all knockout punchers are composed of these three basic components, and therefore operate in the same way, essentially. You turn the screw – which is also known as the draw stud – and this in turn pushes the sharp punch into the sheet metal with a driving force. The punch completely perforates the metal with this force and into the die found on the other side of the metal.

Knock-out punchers are of three main types – manual, ratchet, and hydraulic knockout punch sets:

• Manual – manual knockout punchers are, as the name suggests, operated entirely manually. Since you’ll have to perforate the metal entirely with your own strength, the fact that using manual panel punches is comparatively difficult, at least when compared to the ratchet and hydraulic varieties, is obvious.

• Ratchet – much more easier to use are the ratchet knock out punchers. In ratchet knockout punchers, there is an additional part in the form of a ratchet – that is, a wrench with a socket. This wrench is used to fasten the screw into the sheet metal.

• Hydraulic – the applications of hydraulics are not limited to hydrotest pumps and the like – knock-out punchers also make use of hydraulics. In a hydraulic chassis punch, you will find an additional part in the presence of a hydraulic pump in the knockout punch set. This hydraulic pump can draw the die into the punch with minimal effort. Of course, this set is by far the most expensive out of the three, and usually, you won’t be purchasing these sets unless you’re an electrician or someone similar. Check this link to find out the best hydrotest pump.

When using a knockout punch, a few simple steps have to be followed. Firstly, you need to outline where you will need the holes, and then prepare a pilot hole for each. The pilot is where you will insert the draw stud or the screw into; you can prepare this by drilling a hole into the metal with a drill. The hole needs to be large enough for the stud to go through it. Once this is done, insert the stud into the hole through the die; on the other side of the metal, get the matching punch and thread it onto the stud and tighten them as far as possible. Next, use the wrench or the ratchet to continue tightening the stud – the die will cut through the metal after a while, and create the hole.