The spanner security drive style is a security drive style. It is called a security drive style because it has an unconventional driving method. The spanner security style uses two points on the bit that sit into the recess of the fastener head. This makes if very difficult to remove or tamper with without using the proper bit.
What Are Spanner Security Bits Used For?
Spanner (Snake-Eye) security bits are used for making installations more secure. By adding an unconventional drive stile in public areas, they are much less likely to be vandalized or tampered with on a whim. Spanner screws can be seen commonly on public applications such as: Bathroom dividers and Public Art Displays.
Why are Spanner Security Bits More Likely To Break?
While spanner security bits are one of the best security drive styles around for adding extra security to applications, they do have a big downside. A Spanner bit has two teeth that are inserted into the drive recess for fastening. Due to this style, all of the torque is generated by the force on those two points. This puts them under a great deal of stress when installing. This extreme stress on two points makes them much more susceptible to snapping than other types of bits.
Situations That Cause Spanner Bits To Break and How to Prevent Them
There are several reasons that spanner bits commonly break. Luckily, most of them can be avoided or solved with just some simple changes to the installation process.
|Spanner Bit Snaps During Proper Installation
|Assuming everything is done right and the bit still snaps, it is likely that the bits are of unacceptable quality. Find a reputable dealer with good reviews and use their bits.
|Bits Snapping in Hardwood Applications
|When using harder materials, a spanner screw must have a pilot hole drilled into the material. The bits are not going to be able to provide that much force before failing. The same is true for knots in wood.
|Hitting the second material (if harder)
|If the second material is much harder than the first (attaching wood to metal for example) when the screw hits the second material, it will require more force to drive through and snap. To prevent this, drill a pilot hole.
|Wrong Screw Type
|The screw type is often wrongly chosen for an application. This can cause poor performance while driving and increase force on the bit. Make sure to use the correct screw type for your application.
|Driving the screw below the surface of the material
|When driving a screw, once the head presses against the material, it will greatly increase the friction on the screw. To drive the screw further, the amount of force on the bit will dramatically increase. To solve this problem, countersink the hole before installing the screw if you want the head to be below the surface.
|Proper Drilling Technique
|Make sure you keep your drill straight when installing the screw, especially with spanner bits. Since there are only two points of contact, both need to share the weight evenly. Make sure to apply steady pressure and keep the drill straight, not angled to the fastener.
Spanner Bits: Worth It?
Over-all, spanner security bits are a great drive style and can make it very difficult, if not impossible, to remove without the proper bit. This makes them a common choice for applications that are open to the public without monitoring such as bathrooms or outside art exhibits. *While security drive styles are less likely to be tampered with, it is still easy to get the drives online. Even though they are readily available, the likelihood of tampering is still greatly reduced by using them.
How to Prevent Your Spanner Bits From Breaking | Fasteners 101
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Bob: Welcome back to Albany County Fasteners – Fasteners 101. I’m Bob and today I’m going to demonstrate installing sheet metal screws with a spanner bit and a spanner screw snake eye screw.
Several different names for these out there. We do get some complaints from buyers saying they snapped the bits. In several situations, you could snap a bit. However, if you use it properly you will not snap the bit.
Some applications where you would possibly snap a bit: 1 – Going into hardwood without pre-drilling. If you go into hard wood and you don’t pre-drill and you just try to drive the sheet metal screw into the wood, chances are you will snap the bit or you’ll snap the screw. Either one could happen. I can drive this screw into this soft wood, which is a 2×4, with no issues of snapping a bit and remove it. I’m gonna demonstrate that.
Another way to snap a bit would be running it into a material and then on the back end there’s some metal that the screw cannot go through and you’re trying and you get an immediate stop in the screw. That will snap a bit.
There’s only two teeth on one of these spanner drivers and, of course, they can snap. It’s not the perfect world with these type of bits. Not like a Torx driver or something along those lines. Where they’re very hard to strip out or snap.
So I’m going to demonstrate, right now, installing this and it’s always important to make sure that your bit is square to the screw and the wood so you have positive contact. Put your hand on the back of the drill and you’ll see, I’m just driving it in with no problem. It’ll suck it in and now I just snapped it and why did I snap it?
I snapped it because the head is countersunk, and the screw came to a stopping point. So those who are snapping bits that would give you a reason so you can see here the bit is snapped. I can’t use that bit anymore.
If you’re driving a screw and a natural piece of wood and not over-torqueing it, you should have absolutely no problems with the bits. It doesn’t matter the quality of the bit. You will still snap the bit if you enter that type of situation.