Allen Key Sizes For Metric Screws

The m3 and m4 nominal screw sizes have two drilled holes spaced 180 degrees apart.

Allen key sizes for metric screws.

In the united states larger metric half sizes like 6 5 mm aren t standard in most hex key sets. An allen key size chart often comes with furniture you need to build on your own such as baby cribs outdoor swings or computer desks. For example for an m8 socket head cap screw we need at least 32 8 head size 40mm clearance above the screw for easy accessibility. Torx keys are used for fasteners having a head with a 6 point star or asterisk shaped socket and are frequently used in computers and electronics.

Hold on to it or post it somewhere in the garage where you can hold up the key or socket screw head to the physical picture this can help you to determine which size of allen wrench you need or have on hand. Their purpose is largely to serve specialized applications where size constraints and strength requirements need to be met. These sizes are 1 mm 1 25 mm 3 5 mm 4 5 mm 5 5 mm 7 mm. Non sparking non magnetic allen wrenches can be useful in hazardous environments.

However the 1 4 sae hex wrench will likely work in place of a 6 5 mm wrench. Screw diameter drive size. Refer the following table for metric allen key sizes and dimensions for corresponding socket head cap screw based on iso 4762 din 912 standards. Drilled head metric hexagon socket head cap screws normally are not available in screw sizes smaller than m3 nor larger than m36.

Here we have given the tool size only for metric thread bolts. A hex key allen wrench or allen key is a simple tool used to drive bolts and screws with hexagonal sockets in their heads. Socket flat socket button socket cap set screw 1 6mm. Nominal screw sizes m5 and larger have six drilled holes spaced 60 degrees apart unless the purchaser specifies two drilled holes.

We have given a table for your easy selection of proper size of tools. Lastly there s one other added benefit to having both sae metric hex keys. 2 we use allen key or hex key allen keys or hex keys two are same but name is different in different countries for allen bolts csk bolts button head bolts and grub screw set screw. Less common metric sizes.

While these metric allen key sizes do exist they rarely appear in your basic allen wrench sets. Hex key and torn key sets provide multiple head sizes so they can be used with a range of fasteners.