Remember that old saying that “necessity is the mother of invention”? In the 15th century, carriages started to become the transport of choice for the masses. No longer were fancy carriages just for the wealthy, and no longer did the meager have to travel using broken down carts. As carriage production became more common, manufacturing practices started to become more repeatable and reliable which drove innovation for the tools required to support carriage industry.
The wrench is one such invention that was driven by the necessity for reliable and consistent tools to support the carriage manufacturing industry. In the last 500 – 600 years since that invention, wrenches haven’t changed significantly in function. However, the process to make a wrench has evolved into various methods over time ranging from casting to drop forging, which has reduced cost and increased quality. New features and shapes such as offset wrenches and stubby wrenches have also been developed as more complex assembly needs arose. One such feature that is extremely important is the number of points on the wrench head, which allow the wrench to engage the fastener. Below we discuss the advantages and disadvantages of 6-point versus 12-point wrenches and why each has a place in a mechanic’s garage. The principles discussed here also apply to 6-point and 12-point sockets.
Perhaps the biggest advantage of a 6-point wrench is that it will give you the most surface contact with a typical bolt head, and will thus significantly reduce the likelihood of stripping the fastener. This is obviously a huge advantage as a rounded bolt head can come at the cost of significant time and frustration. For this reason, you’ll notice that most impact sockets tend to be 6-point.
One of the disadvantages of a 6-point wrench is that you need some significant space to be able to use them. In general, a 6-point wrench requires 60 degrees of rotation (360 / 6 = 60) minimum in order to be able to reposition your wrench on a fastener for another turn. If you have the space available for that much wrench movement, then this is no problem at all. In a tight engine compartment, you may find that your space is limited and that you have a hard time repositioning your wrench on a fastener which forces you to use the open end of the wrench or pick another tool.
The basic function of a 12-point wrench is the same as the 6-point wrench. Having 12 points will offer the ability to move the wrench less per turn (only 30 degrees minimum!) while still allowing you to reposition your wrench on the fastener. This allows you to use the wrench in tighter spaces without worry. The added versatility is why you’ll see 12-point configurations for many combination wrench sets and wrenches in mechanic’s socket sets.
While a lower space requirement to turn your fastener is beneficial, you must also consider the way in which the wrench contacts the fastener. A 12-point wrench has less contact with a typical fastener head and as such runs a significantly higher risk of stripping a fastener head if you aren’t careful. This is particularly true because a 12-point wrench contacts fasteners at the corners which is where fasteners round off.
When it comes to 6-point versus 12-point wrenches, each definitely has their advantages. Which is best to use depends mostly on a combination of the space available in your engine bay for the wrench to move and how careful you are willing to be when it comes to stripping fasteners. For limited space situations, a 12-point wrench makes the most sense. If space isn’t a concern, we usually recommend going with a 6-point wrench as that will reduce your chances of fastener damage. Happy wrenching!