Unfortunately the stamps are not all that accurate and my
stamped lettering always comes out crooked.
Here’s one solution, though not one practical for most of us.
Though the steel stamps used to stamp metals are usually not accurate,
the old typemetal type used with old style letterpress printing
presses IS accurate, and comes in a very wide range of type sizes and
styles. Nowadays, it’s been replaced mostly by more modern printing
methods, but sometimes you can find large lots (many pounds at a
time) of the old type available, often for pennies or a few dollars
per pound. This stuff is just a tin/lead alloy, so obviously it
won’t stamp metal. But if you set up the type in a suitable frame
with the phrase you want, lay a sheet of saran wrap or similar
plastic wrap over a piece of sheet wax, you can impress very precise
and detailed lettering into the sheet wax, which can then be cast.
The casting ends up with nicely impressed lettering, which differs
markedly in effect from the main competitor for this, photo etching,
in that with a photo etch, the precision surface is the outer surface
of the metal, not the recessed one. It thus can be altered to
polishing, etc. With the pressed in type method, the precision shape
is the bottom of the impression, so polishing or finishing of the
outer surface doesn’t affect the quality of the image.
Other ways to get what you want are variations of photo etching.
You can draw, or use a compter typography program (your word
processor) to lay out the precise image you wish, and send this to a
graphic arts place which will be happy to make a printing plate for
you, in etched zinc or magnesium. This is used like the type I just
metioned, differing from it in that the real type has a more precise
side slope to the letters than the photoetched printing plate. But
the difference isn’t all that much. The zinc plate, if made so the
writing reads correctly right on the plate, can also be just molded
and cast, for raised letters, or if you made the plate so the letters
are etched in, (which in printing would give you a black background
with white letters), then molded and cast, you’ll have impressed
letters somewhat like stamped in ones. One can also have rubber
stamps made, in either raised letters or recessed ones, in the same
way. If you tell the shop not to mount the rubber, then you end up
with a flexible rubber sheet with your design on/in it, which can by
itself be invested and cast directly, without molding. The rubber
mold method is also useful if you wish to have the lettering follow a
curve, since the rubber is flexible, and can be glued to curved sheet
material (wax or plastic) to make the model for casting.
And if you already have stamps, it may be simplest to just stamp
into wax sheet, with saran wrap as the seperator. the wax sheet is
cheap, and you can try several times, learning the quirks of the
stamps, till you get it right. You could even do this in the wax just
to practice, and then attempt to stamp the metal once you know how to
adjust the positions of the stamps.
Hope that helps.