On Sat, 9 Sep 2017 08:21:13 -0400, "Michael A. Terrell"
wrote:

wrote:
I've always wondered how they paint on the colored stripes. I put "how
do they paint the stripes on resistors" on google, but all I got was
links explaining how to READ color codes.

Has anyone ever heard anything about this process?

Isn't it obvious? Early resistors were hand painted, then they
developed machines for the job.

It's a no brainer they use a machine. My question goes much deeper. How
does the machine do it? Are the paints applied by a paint brush, or
something like a felt tip marker, or maybe some sort of spray method?
Once the correct colors are chosen for that batch of (whatever value),
how do they rotate them so the paint is not smeared. I can only assume
they are picked up by their leads, not the body, and somehow rotated by
their leads too.

I do believe the early resistors, especially those ceramic types that
had colored dots on them, were probably hand painted. I have also noted
that the old bumble bee caps often had irregular stripes, where the
paint was thicker in spots, thinner in others, and the edges were not
always precise.

There is a series on tv, which is usually only shown on Saturday
mornings, during the kids shows, that show how an item is made. The ones
I remember are making candy, and making lightbulbs (incandescent). They
show the entire process, start to finish, and show each step both in the
machines and how workers are involved. I cant recall the name of them
programs, and have not seen any in a long time, but they are quite
interesting. That lightbulb one was extremely interesting. Each bulb is
tested in a machine and workers watch ot make sure they light up. Seeing
this, (on tv or youtube), for resistors would be interesting. Too bad
they dont have more stuff like that on tv, rather than the usual garbage
that is mostly on the channels these days.

One thing I do know, is that most small electronic parts with wire
leads, leave the factory in the form of ladders. Meaning that 100 or
1000, or any other number of them are one long strip being held together
by 2 strips of paper around the leads, to form what looks like a ladder.

So, if you worked at Zenith assembling radios, there would be rolls of
those ladders for every value of resistor, capacitor, etc, needed, at
each work station.

By the way, there is a good documentary video on youtube that shows
radios being made at Zenith. It was filmed in (If I recall correctly),
the 1950s. Worth watching!