Re: Ruby - How about a sight glass?

[Harry Wade]

At 08:17 PM 5/3/01 -0500, you wrote:
>>Maybe I'm missing something. Wouldn't there have to be a bushing silver
brazed into the backhead (or somewhere) on the boiler to use a glow plug as
a level sensor?   If you were going to do that you might as well just go
ahead and put a regular sight glass in. Right?
>>Trent

Trent,
    You aren't missing anything.   But maybe what is needed is sideways
thinking, as Mike Chaney pointed out.  The penetration needed for a working
steam fitting and the penetration needed for an electrode are, or CAN be,
two completely different things.  I could see an electrode being made from
a #2-56 screw.  That would be roughly a #9 BA.   In my opinion a thread
this small could be made straight into 1/16" copper sheet without a bushing
and be successful.  A .078" hole is considerably different than the 3/8" or
so hole needed to fit a bushing for a fitting.


Regards,
Harry Wade
Nashville, Tn