Lastly there s one other added benefit to having both sae metric hex keys.
Allen key sizes.
In the united states larger metric half sizes like 6 5 mm aren t standard in most hex key sets.
A hex key or allen key is a simple tool used to drive bolts and screws with hexagonal sockets in their heads.
Substituting uncommon hex sizes.
Drilled head metric hexagon socket head cap screws normally are not available in screw sizes smaller than m3 nor larger than m36.
The m3 and m4 nominal screw sizes have two drilled holes spaced 180 degrees apart.
The good news is that just about every tool manufacturer has a range of allen wrench sets you can buy.
These dimensions of allen keys can be used to check the accessibility of your bolts were space is limited.
Stan dard sae hex key sizes inches metric hex key sizes mm notes compares standard and metric allen wrench sizes where they closely match and where they don t wrench equivalence 15 key set.
Their purpose is largely to serve specialized applications where size constraints and strength requirements need to be met.
Hex key equivalent sizes.
Differ ence in 1 1000s of an inch.
There are a few ways that you can tell what hex key you may need to finish a project tighten a set of screws or loosen an old screw.
These standard allen keys offer a larger range of sizes than the stainless types.
Allen wrenches are convenient and helpful.
While these metric allen key sizes do exist they rarely appear in your basic allen wrench sets.
Allen key also known as hex key hexagon key socket key ln key sizes and its dimensions can be very handy while designing and selecting fasteners for your application.
Hex plus offers a bigger contact surface in the screw head and so reduces the chance of wear and rounding off the corners in allen head screws.
These sizes are 1 mm 1 25 mm 3 5 mm 4 5 mm 5 5 mm 7 mm.
The tool is usually formed of a single piece of hexagonal rod of hard steel with blunt ends that are meant to fit snugly into the screw s socket bent in an l shape with unequal arms the tool is usually held and twisted by the long arm creating a large torque at the tip of the.
Nominal screw sizes m5 and larger have six drilled holes spaced 60 degrees apart unless the purchaser specifies two drilled holes.
In that case you ll want a range of allen wrenches to make sure you have the right size for every particular need.
However the 1 4 sae hex wrench will likely work in place of a 6 5 mm wrench.
Less common metric sizes.
Interchangable 0 028 and 0 7mm.
You can find a chart of the allen wrench sizes from any manufacturer.
