A utility or box cutter knife is one of those universal tools you’ll find in almost every workshop, garage, and warehouse worldwide.
They come in various shapes and sizes because almost every manufacturer will make their own, but the way they’re assembled doesn’t change much.
If you needed to change the blade on your utility knife recently, then you may be wondering how to put a utility knife back together again.
Stick with us as we explain how to change utility knife blade, including how to put a blade in a utility knife and how to reassemble the knife afterward.
Dismantling the Knife and Changing the Blade
Before we jump into how to put your utility knife back together, let’s take a quick look at the proper way to dismantle one and how to change the blade.
How To Dismantle a Utility Knife
Before attempting to dismantle your utility knife, you should fully retract the blade into the knife body.
That’s because even blunt blades can cause serious injury.
- Standard Utility Knife
There’s a standard utility knife kept together with just one screw in its body.
Locate the screw situated halfway down the knife’s body and then, using a screwdriver, take the screw out.
Turn counter-clockwise to loosen it (lefty-loosey), and you’ll only need a flathead or Phillips screwdriver to take it apart.
If your knife is different, then a quick inspection of the knife’s casing should be enough to work out how to take it apart.
Once the screw(s) is out, the body of the knife will split into two, so you can pull the top half of the body off the bottom half.
How To Change Utility Knife Blade
Next up is changing the blade in the knife. This is where many people fail since reinserting the new blade correctly can be tricky.
Knowing how to put a blade in a utility knife is as simple as remembering how you took it out.
So, before you touch the old blade, place the two halves of the knife flat on a table.
Take the half that houses the blade and place it closer to you, facing the blade sliding mechanism towards you.
When you remove the blade holder from the knife, you’ll primarily use the sliding mechanism as your point of contact for obvious safety reasons.
Take a close look at where the notches in the blade are, how it sits in the holder, and its relationship to the sliding mechanism.
Only now are you ready to begin!
Step #1: Remove the Blade Holder
Once you’re confident you’ll remember how to replace it, you can carefully remove the blade holder from the knife case and then set it down.
Step #2: Remove the Old Blade
Carefully slide the old blade out from the holder.
Step #3: Locate the New Blade
When you’re changing the blade in your utility knife, you may find that you have spare blades in the handle already.
If not or if you’ve run out, you just have to make sure the blades you buy match the type you had, but they don’t have to be by the same manufacturer.
Step #3: Replace the Blade
Keep the blade holder steady by using the sliding mechanism, which should still be pointing towards you.
Slide the new blade into the holder, with the sharp edge pointing away from you, matching up the grooves into their slots.
Step #4: Put the Blade Holder Back
Put the holder in the knife housing in the same place from which you removed it.
In case things have been moved, you can easily identify where it goes by using the sliding mechanism as a guide.
There is only one place this mechanism will slide into place, which is on the longer or pointier side of the knife case.
Once you have the blade holder back in place, make sure you slide it all the way back into the housing.
This way, the blade doesn’t stick out of the end.
How To Change Blade in Folding Utility Knife
If you have a folding utility knife, then how to change blade in folding utility knife is much the same as the non-folding varieties.
Except in the case of a folding utility knife, the blade holder acts as the folding section and will already be poking out of the knife.
It may require you to take some extra screws out to get inside the blade holder, but most folding utility knives have quick-change buttons for blade replacement.
They’re usually located at the top of the blade (the blunt side), and you just need to press the button while you remove and replace the blade.
How To Put a Utility Knife Back Together
Once you have the blade and blade holder back in the utility knife, putting the knife together should be a breeze.
However, before you put it back together, you may wish to oil up the sliding mechanism while you have it open.
In which case, add oil and use a cloth or paper towel to spread the grease up and down the mechanism.
Then, take half of the knife case that doesn’t have the blade in it and put it on top of the half with the blade in it, matching it up to fit correctly.
Snap the two halves into place and then replace the screw(s) into the hole or holes from which they came.
Tighten them up with your screwdriver in a clockwise motion (righty-tighty!).
You can make sure you’ve put everything back together correctly by simply sliding the blade out and back in again.
Take Your Time
When people ask how to put a utility knife back together, it’s usually because they’ve tried to do it in a hurry.
Unless you’re changing blades all the time, it’s easy to forget how and where to place the blade after you’ve removed it.
So, just in case you ever find yourself in this position again, head straight to step three of how to change the blade!
If it’s time for you to replace your trusty utility knife, then look for the highly-recommended utility knives to make sure you’re investing in the right product.