Hinges and Hardware 101 - Dimensioning a slotted hole

Slots, also known as obrounds or ovals, need to have a dimension to identify their size just like any other perforation. When dimensioning holes, all is needed is the diameter, but how does one call out a slot size?  A slot is really just an elongated hole, so first you'd need to know the hole diameter. Then you can either call out the dimension from center-to-center on the holes making up the ends of the slot or just call out the overall length. Slots are typically made with punching dies. It is helpful if you can use a size that we already have a punch for, but we can certainly offer any size you want with a tooling charge. Click here for more information on slotted holes.