Stencil -"CPM154CM" - one image - approx 1" x 2 1/2" in size
Stencils by IMG Marking Group..
These are commercially made stencils created by the IMG Company. I had several different sheets of stencils made so some one can buy just one or two stencils and not have to pay a set up fee.
These are in Bold, Verdana true type font, 8point size.
These stencils are for electrochemical impressions using an etch machine. These will measure approximately 1" x 2 1/2". There is one image per stencil. You should get several dozen impressions from one stencil. You might get a hundred impressions if you don't burn your etches too deeply and you clean them up properly. It's really hard to say. I tend to use a stencil like this for an average of 50 to 60 impressions and then pitch it.
Tip to extend stencil life: Clean your stencil by making an impression on a carbon block through a dampened cotton pad to remove any residue metal. When you are through with the stencil, rinse it with fresh water and blot it dry. Too high of power setting on your etch machine will fry the stencil and shorten the life. Try a lower setting but longer times.
CRA means cold rolled annealed and is important to be in the description. It means the steel was pressure rolled while cold but was annealed again to relief the stress and take it to the softest state from rolling under tremendous pressure.
HR means hot rolled and this steel was rolled to thickness usually during the smelting process but maybe later. The steel generally will be half or nearly fully hard depending on the type. It may often have mill scale residue. This steel can be easily forged. It can also be ground via stock removal. Drilling a hole in the tang maybe hard to do with out a carbide bit.
HRA is the same but the steel was later annealed to relieve stress and make it as soft as possible for easier machining. Several companies produce "powder" smelted steels. This is a premium smelting process that improves the mixing of alloy content and generally produces a finer grain structure as a result. The powder steels are nearly always annealed and can be assumed to annealed unless noted otherwise.
