Punches
Knockout punch kits cut clean, accurate holes in boxes, panels and trunking without tearing thin steel or wasting time with a holesaw.
If you're fitting glands, conduit entries or panel gear all day, a proper knockout punch saves a lot of grief. Manual sets suit lighter board work, while a hydraulic knockout punch or cordless knockout punch makes repeated holes in thicker steel far easier. Sparkies and panel builders use them for cleaner finishes, better fitting hardware and less burring to sort after.
What Are Knockout Punches Used For?
- Cutting clean conduit and cable gland entries in steel back boxes, enclosures and distribution boards where a ragged drilled hole will slow the job down and look poor.
- Punching repeat holes in control panels and switchgear so glands, connectors and fittings sit properly without filing sharp edges for half the afternoon.
- Working on stainless or thicker sheet metal with a hydraulic knockout punch when hand force alone starts becoming hard work and consistency matters across a full panel.
- Installing site temporary power, plant wiring or workshop boards where a knockout punch set gives you the common trade sizes in one case and keeps the finish neat.
- Opening out panel work after starting with Cone & Step Drill Bits when you need an accurate pilot before drawing the punch through.
Choosing the Right Knockout Punch
Sorting the right knockout punch is simple: match it to the panel material, the hole size, and how many holes you are actually doing in a day.
1. Manual vs Hydraulic vs Cordless
If you are only doing the odd hole in lighter gauge boxes, a manual knockout punch set is usually enough. If you are punching thicker steel, larger diameters or repeat holes across boards and panels, go straight to a hydraulic knockout punch or cordless knockout punch and save your hands.
2. Check the Sizes You Actually Use
Do not buy a set full of sizes you will never touch. If most of your work is conduit and common cable glands, make sure the set covers those properly before anything else, otherwise you will still be back at the van improvising.
3. Match It to the Material
Mild steel is one thing, stainless is another. If you are regularly working on tougher enclosure material, make sure the punch is rated for it and do not assume every sheet metal punch will handle stainless without extra effort or wear.
4. Think About Access and Repeat Work
If you are in cramped panels or working overhead, a battery knockout punch can be a better shout than hauling a larger hydraulic setup around. For bench work or planned panel assembly, hydraulic gear usually gives you easier, more controlled punching on bigger runs.
Who Uses These on Site?
- Sparkies use knockout punches for consumer units, adaptable boxes, panel boards and trunking because they give a cleaner gland hole than forcing it with a drill and file.
- Panel builders swear by them for repeat work on steel enclosures, especially when multiple gland sizes need to line up properly across a row.
- Industrial maintenance teams keep a hydraulic knockout punch handy for plant rooms and control cabinets where thicker steel and awkward access make drilling a faff.
- Mechanical and electrical fitters use them during first fix and final connections when they need tidy conduit knockout punch results that will pass inspection and not chew cable protection.
The Basics: Understanding Knockout Punches
A knockout punch does one job properly. It pulls a punch through sheet metal to cut a clean, round hole, which is why sparkies use it when drilled holes and holesaws leave too much mess behind.
1. Punch and Die Working Together
You drill a pilot hole first, pass the draw stud through, then tighten or power the punch through the metal into the die. The result is a neater hole with less distortion, which matters when glands and conduit fittings need to sit flush.
2. Manual, Hydraulic and Cordless Drive
Manual types use hand force and suit lighter jobs. Hydraulic knockout punch models multiply that force for larger holes and thicker steel. Cordless knockout punch tools do the same sort of work faster when you are moving around site and punching repeatedly.
3. Size Matters More Than Speed
The important bit is choosing the right punch size for the fitting going in, not just making a hole that looks close enough. Get the size wrong and the gland will not seat properly, which is exactly the sort of snag you do not need at final fix.
Knockout Punch Accessories That Save Time on Site
A few proper extras keep the holes clean, the tool working and stop you bodging panel work halfway through the job.
1. Punches & Dies
Keep spare or replacement Punches & Dies handy if you work across different gland and conduit sizes. It saves wearing out your main set or getting stuck when one size takes all the punishment.
2. Cone & Step Drill Bits
A pilot hole has to be clean and in the right place or the whole punch setup starts badly. Cone & Step Drill Bits are ideal for opening thin metal accurately without grabbing and chewing the panel face.
3. Holesaws & Accessories
Not every hole on a job needs drawing through with a punch. Keeping Holesaws & Accessories nearby gives you another option for larger openings or rougher work where finish is less critical.
Choose the Right Knockout Punch for the Job
Use this as a quick guide before you pick a set or tool.
| Your Job | Category or Type | Key Features |
|---|---|---|
| Occasional holes in light gauge boxes and trunking | Manual knockout punch set | Simple draw stud setup, common conduit sizes, easy to keep in the tool bag |
| Repeat gland holes in panels and enclosures | Hydraulic knockout punch | Higher punching force, less strain, cleaner repeat work in thicker material |
| Moving around site doing regular panel entries | Cordless knockout punch | Battery powered speed, less setup, useful for repeated holes away from the bench |
| Mixed conduit and gland installation work | Knockout punch set | Multiple punch sizes, carry case storage, covers the most used electrical hole sizes |
| Stainless steel or tougher enclosure material | Heavy duty hydraulic set | Material-rated punches, stronger draw components, better suited to hard panel stock |
Common Buying and Usage Mistakes
- Buying by price instead of hole sizes is a common one. If the set does not cover your usual conduit and gland sizes, it will spend more time in the van than on the job.
- Using a manual punch for large repeat holes in thicker steel soon becomes hard work and can slow the whole install down. If that sounds like your week, step up to hydraulic or cordless.
- Skipping the pilot hole or drilling it badly throws the punch off line. Start clean and square, otherwise you risk damaged threads, poor cuts and a marked panel face.
- Assuming every metal hole punch tool will handle stainless is asking for trouble. Check the rating first, because tough material will expose weak punches straight away.
- Forgetting replacement consumables is another avoidable hold-up. Worn punches and dies give rougher holes, so keep spares ready if you rely on the kit every week.
Manual vs Hydraulic vs Cordless
Manual Knockout Punch
Best for lighter gauge steel, occasional use and smaller hole sizes. It is slower, but simple and dependable when you do not need big force or all-day repetition.
Hydraulic Knockout Punch
This is the better option for thicker panels, larger diameters and regular enclosure work. It cuts effort right down and gives more controlled punching when the material starts fighting back.
Cordless Knockout Punch
Ideal when you are moving around site and doing repeated holes without wanting hoses or a manual ratchet setup. Usually costs more, but it earns its keep on busy installation work.
Knockout Punch vs Holesaw
A knockout punch gives a cleaner, truer hole in thin steel and panel work. A holesaw is more flexible across materials, but it can leave more burring and needs more cleanup for electrical finish work.
Maintenance and Care
Clean Swarf Off Straight Away
Wipe down punches, dies and draw studs after use so metal filings do not score the threads or sit there pulling in moisture. It takes two minutes and saves a lot of grief later.
Lightly Oil Threads and Moving Parts
A small amount of lubricant on the draw bolt and threads keeps the action smooth and cuts wear. Dry, gritty threads are usually what makes a set feel rough and tired before its time.
Check Cutting Edges for Wear
If holes start coming out rough or you notice more force is needed, inspect the punch and die. Worn edges mean poorer results and more strain, so replace them before they start damaging panel work.
Store the Full Set Together
Keep sizes, spacers and studs in the case they came in. Losing one small part on site can turn a full knockout punch set into dead weight for the rest of the day.
Inspect Hydraulic Gear Before Big Jobs
On hydraulic units, check seals, hoses and pressure operation before heading into a panel install. If it feels weak or leaks, sort it before site rather than halfway through a board room.
Why Shop for Knockout Punches at ITS?
Whether you need a compact knockout punch set for standard electrical work or a hydraulic knockout punch for bigger panel jobs, we stock the range that matters. You will also find related kit across More Power Tools and support tools like Hydraulic Cable Crimpers. It is all held in our own warehouse, in stock, and ready for next day delivery.
Knockout Punch FAQs
What is a knockout punch used for?
A knockout punch is used to cut clean, round holes in sheet metal, boxes, enclosures and panels for conduit, cable glands and fittings. It gives a tidier finish than most drilled holes, with less burring and less filing after.
What size knockout punch do I need for conduit and cable glands?
You need to match the punch size to the actual fitting being installed, not just the conduit size written on the drawing. Check the gland or connector entry size first, because one wrong assumption can leave you with a loose fit or a panel that needs reworking.
Can a knockout punch cut stainless steel?
Yes, some can, but not every set is meant for stainless. Be honest about the material you are working with and check the punch rating first, because stainless will quickly show up under-specced gear and worn cutting edges.
Do you need to pre-drill a pilot hole for a knockout punch?
Yes, in normal use you do. The draw stud has to pass through the material before the punch can pull through the die, so a clean pilot hole is part of doing the job properly.
What's the difference between a hydraulic and a manual knockout punch?
A manual knockout punch relies on hand force and suits lighter, occasional work. A hydraulic knockout punch multiplies that force, so it is better for larger holes, thicker metal and repeat punching where speed and reduced strain matter.
Will a knockout punch leave a cleaner hole than a holesaw?
Yes, usually in thin steel and enclosure work it will. A knockout punch is made for neat, round entries with less distortion, while a holesaw is more likely to leave rougher edges that need dressing back.
