Re:Growing a company that sells miniature construction suppl...
by Animats on Wednesday February 21, 2018 @03:29PM
(#16432687)
Most expensive is "Double Shot", two separate colors of plastic is used, first the legend is molded in one color (kinda built on a grid of plastic) then it's placed in the full keycap mold and the "background" plastic is shot into the mold filling all the empty space. The legends on these keycaps obviously cannot fade or wear off.
Yes. HP calculators had that.
There's another way for small volume. Laser engrave the legend with a CNC laser cutter. Then brush on laser marking powder, which is very similar to printer toner. Rerun the engraving pass at very low power, hitting the same spots just engraved. Power has to be low, just enough to melt and seal the toner, not vaporize it. Then brush off any remaining powder. This is good for cover plates with legends, signs, and such. The letters are slightly below surface level, so they tend not to wear off too fast.
Yes. HP calculators had that.
There's another way for small volume. Laser engrave the legend with a CNC laser cutter. Then brush on laser marking powder, which is very similar to printer toner. Rerun the engraving pass at very low power, hitting the same spots just engraved. Power has to be low, just enough to melt and seal the toner, not vaporize it. Then brush off any remaining powder. This is good for cover plates with legends, signs, and such. The letters are slightly below surface level, so they tend not to wear off too fast.