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gauges

Why are so many people so anti gauge? It seems especially suprising to me
with this bunch of people; I mean here we have a group that is much more
computer literate than most of the people in the country and yet won't
embrace "modern" (and it certainly isn't) technology in bombarding.
I, like Dave (sorry to drag you into this), spend many hours each week
talking to people who have tubes that are going bad.  Sometimes I think it is
unfourtunate that neon doesn't go bad instantaniously - just blow up on the
burn in table or something - so that problems at thier source would be easier
to find and eliminate.  But they don't.  The problems may begin to occur
months after the tube is made, possibly years.
If you are not using gauges you are guessing.  You are relying solely on your
preceptions as to what the tube is doing.  But your preceptions change all
the time: how fast you preceive you are  going in a car depends on many
variables - road condition, weather, other cars, changes in your car, etc.
 How you preceive the tube is also variable: dia. of tube, how much moisture
is in the tube, different manufacturers' phosphor blends (color while
bombarding, how hydroscopic, how much gas the electrodes give off while
converting), changes that all manufacturers make in any product without
telling you.  I am NOT advocating bombarding by only looking at gauges, but I
am advocating making bombarding a consistent and repeatable process.
When a job does go bad, trying to figure out what went wrong is always
difficult.  If you are using gauges (and you are keeping some simple records)
it can be easier.  If you are not using gauges, you are relying on ever
changing preceptions (just what color is "lightly  charred"? Gotta PMS number
for that?), and left with too many variables to look at.
Gauges are not perfect.  They do get out of calibration.  However the company
that I am most familiar with will recalibrate any gauge they sell at no
charge - you only need to send it in with a return number.  I would be
suprised if other mfg's don't do the same.

Since other posts have been mostly about temp gauges and paper, let me make a
few comments about both: I have heard "newspaper only" many times.  I have
heard how mech temp gauges are obviously off because different pieces of
paper char at different times.  Did you ever stop to think that maybe you're
proving that paper is inaccurate?  Have you considered the newsprint shortage
that's been going on for the past few years? Do you think that efforts to
make newspaper better/cheaper/longer lasting/more easily recycled/ recycled
have an effect?  These things are done to make for better newsprint, not to
make better temperature indicators!
With paper are you sure where that 150 - 175 degree C point is where most
mfg's say to change pressure and mA?  Do you know that the glass is hot
enough?  Do you know that (at bombarding pressures ) going over 300 C may
damage the phoshpor/emmiter (how hot was darkly charred?), and are you sure
that you're not above that?

If for whatever reason you won't use one of the many good temp gauges on the
market, at least think about using thermo-crayon, as it was designed to be a
temperature indicator, and it does give a specific change at about 160 C.

I didn't mean to get so wound up about this, but I'm getting ready to go over
to the shop now and on Mon and Tues I spent two hours each day trying to
figure out big jobs that have gone bad for other people.  I'm behind on my
own work and the lack of sleep is getting to me.
Morgan
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