123 Blocks are the unspoken whipping boy of the machining world. They get used for a great number of things to include clamping, spacing, bolting and many other things. The reason for this is they are hardened and surface ground to the exact specification of 1″ by 2″ by 3″ which makes them very useful because they are consistent. I have had the same set for almost 18 years and the only issue is they are dirty.
Above you can clearly see the 1 Inch side.
Above you can see the 2 Inch side.
The final side being 3 Inches.
In this above example you can see that I am using the 123 Block to stabilize a depth mic as I measure the height of the die. If you do the math you will realize that the die is .739 tall on that side at least.
These blocks are easy to take care of just oil them and do some light cleaning. Using light steel wool is OK to clean them however non-abrasives are the preferred way to clean them. As long as they are hardened and surface ground they should last for years.
Fecke – KJ4ZRZ