Hi Jose!

I use a tube cracker that is a combination of the Coleman (1981) and
Caldwell et al. (1983) designs (see references previously mentioned by
Andrea Lini).  I buy glass ball-and-socket joints from Kontes and have them
make some minor modifications (although any glassblower could do it too).
I have the end of 18/7 ball joint sealed, and a 3-mm-thick, 10-mm-diameter
fritted glass disk inserted in the 18/9 socket joint.  The tube cracker
accepts 6-mm O.D. glass tubes that are about 170 mm long.  The
ball-and-socket joint is greased with Apiezon L and secured with a pinch
clamp.  The open end of the socket joint is attached to the mass
spectrometer inlet with an Ultra-torr Cajon connector rather than an Ace
Thread connector.

E-mail me directly if you are still interested in dimensions and Kontes
part numbers.

Steve

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Stephen S. Howe                         Office:  (518) 442-5053
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