Adapter Thread Help

101 Spearfishing TAB above for more DETAILED information on threads.
This is just a small guide for adapter selection.
Going to your local Hardware Store to match Bolts and Nuts is one common method.
Hardware Store has limited selection, Too many Threads out there.

5/16"-24 means the Bolt is .3125" Diameter and there are 24 threads per Inch.
6mm-1 means the Diameter of the bolt is 6mm and there is 1 thread every millimeter.

Basic Terminology of a Thread.

Here is an example of counting Thread Peaks to get the Pitch. ( SAE sizes)

Here is an example of counting Thread Peaks to get the Pitch. (METRIC sizes)

** This is a 6mm thread with a pitch of 1mm per thread. The 1mm pitch is what is common to spearfishing gear.

Did you know that there are actually 5 different 6mm threads? Other 6mm pitches are [ .5 : .7 : .75 : .8 : 1.0 ]

Pictures of threads can be sent to me for help. Note how a Ruler or gauge is in the picture for size reference.

FIXED Pitch Gauge to measure

Here is a sketch of an Adapter Request. Note the Diver telling me what he is using it for along with thread depth, shoulder diameter, etc. A sketch doesn't have to be all fancy just enough so I know what to make. If you miss a detail, I will ask or assist with what will work best.

Here are some Side by side photos to show Size and Thread pitch of common Spear-O Threads

Swagelok - Identifying Thread Pitch & Size

Swagelok is a company I have used for many years in the vacuum industry,

They put together a nice presentation.

Questions: ( john@linghunt.com ) [ 707-477-0869 ] PST , give me a call - drop a note.