Hello Harry,
I see your point. Both use the same materials, only in a different way. I
honestly don't know why I don't like the compression type fittings. They get
used in almost everything, not just steamers, and usually give no problem if
installed properly.
The sight glass that I was talking about has two parallel drawbars running
along the outside of the glass. Very similar to what you described. They keep
the ends, containing the o-rings, pulled tight to one another with the sight
glass trapped between them. The end fitting is basically a cup that has the
o-rings inside to seal against the ends of the glass. In this configuration,
the drawbars would not need to be sealed. I think we're talking about very
similar designs, if not the same thing. If I'm wrong let me know because I
would like to explore my possibilities before I get too much further along on
this project. Thanks.
Later,
Trent
Harry Wade wrote:
> both types use a ring of captive
> flexible material to make the seal, they just make it in different ways.
> The thing with the drawbar type gauge is that instead of two ends to seal
> (the glass tube) you have four, the ends of the tube and the ends of
> drawbar. Actually, I prefer a variation which you would almost always find
> in full size practice, which is compression nuts and rubber rings on the
> glass and a pair of drawbars outside the glass connecting the upper and
> lower fittings. You could use this arrangement on your glass, keeping the
> O-ring end seals, and eliminate potential problems with sealing the
> drawbars ends. All you'd have to do is machine or solder a set of "ears"
> to the end fittings.
