There is one partickular type of pop rivet gun frustration: it won’t grab onto the mandrel. You think: “Pull the trigger and the rivet will go on,” but nothing happen except the nose spinning around. The rivet don’t even stick into the jaws; it’s hanging there freely, telling you something is wrong with method, material or the mechanism.
That’s bad news because normaly this means damage control time (tools and/or stripped threads) unless you stop right then and there and fix it. But most likely, you don’t actualy need a new gun, as many grip issue arise from simple oversights like a worn spring or dirty jaw. Those is nearly always fixable within a few minutes of attention.
Quick Fixes For A Rivet Gun That Won’t Grip
Clean the Rivet Gun Nose
Cleanliness Rivets is held together by exacting mechanical fit and friction between the mandrel and the jaws. Anything that create a lubricant such as metal shavings, oil or grease can interfere with the jaws’ ability to bite down correctly. So remove all the gunk in the nose with a rag and use compressed air to blow it all out of the jaws, then let everything dry well.
If your gun have just been stored next to an oil can with a leak, this is probably it.
Check Rivet Diameter Size
Finally look at actual rivet itself. A common error is using the incorrect diameter rivet.
Too big and it may or may not go in. Too small and it will rattle loose as you use it. Always make sure your rivet matches the diameter of your gun’s nose.
The jaws don’t get a good enough bite on the rivet if it are too small. Typically most guns is marked with their capacity. An 1/8 inch nose requires an 1/8 inch rivet.
It seems like common sense, but I’ve seen those mixed box before. Read marking on head of the rivet.
Inspect Worn Jaws
Next is the jaws.
These are metal teeth that grab the softer metal in the mandrel. Over time, however, those teeth will wears. They’ll round off and get all smooth so there’s no tooth for the teeth to grab.
Check them inside the nose, and if you see any polish or shine on the insides of the jaws, it’s probably time. On heavy-duty tools like this, this can be a common failure point and replacing the jaws are easy and affordable and gives you instant gripping power again.
Test Spring Tension
Tension also matter, spring tension.
There’s a spring mechanism that holds the jaws closed and when that spring is broken or weak, they don’t come together with enough force. It’s common on old tools and tools that get a lot of use. You’ll feel the trigger pull but the jaws won’t close; they remain open.
When a spring are tired, it’s usually mushy. If you think yours has been worn out, disassemble the nose and see if there is any cracks in the spring. A new one only costs pennies but go a huge distance toward making your tool perform well.
Match Mandrel Material
The issue may not be the tool at all, it could also be the mandrel itself. Aluminum mandrels are typicaly soft and easily gripped while stainless steel mandrels is far harder. If your jaws are dirty or worn, they can slips on stainless steel mandrels.
This will make things more difficult for your gun if you are switching to stainless rivets. This is one of the tradeoffs. You get corrosion resistance but give up a little ease of use when installing them.
Make sure your jaws is sharp and clean if you’re going to go stainless, and think about upgrading to something with hardened jaws if you mostly use stainless. You should of checked that first.
Lubricate Trigger Mechanism
Lastly, examine the trigger mechanism.
Dirt in the pivot or a bent linkage will stop the trigger from moving all the way through. As a result, the jaws might not close all the way. Make sure handle slides easily and wipe out the trigger area.
If the mechanism feel sticky, lubricate the moving parts with a light oil instead of grease, because grease attract dirt. Smooth easy movement is what you desire, not “sticky” resistance.
Most of the time, a non-gripping rivet gun is a “maintenance” situation and not necessarily a death sentence.
Inspect your jaws for wear, check your rivet size, and clean up your nose; these steps solves most problems. Keep your tool maintained. Keep at it, and when you pull the trigger the next time out, you ought to feel that bite you’re used to.
That solid connection is what makes the job easy.