Siphon brewing tips?

[Redswing]

On vacation at my in-laws house, found an old Cory siphon pot from a few generations ago in a basement closet. Had two glass Cory filter rods (stamped with patent # 1927287), an extra rubber gasket, and a metal flap to put over the bottom carafe when the top part is removed.

I have a Yama at home with the spring and metal cloth-covered filter, so haven't used the glass filter rod before. I've tried this one three times, and each time it stalls going down. It seems to be draining down fine, then I hear a bit of a sucking sound and am afraid of imploding the thing so I rock the top globe a little, and at that point it stalls. Is my fear irrational? Perhaps that sound is normal? It would just be like me to break something like this while I'm here, so I am hesitant...

You'll about my grind, surely. I'm using the only thing here, a chopper style grinder, going for pretty course just to see if I can get it to work.

 

[peterjschmidt]

I'd blame it on your grinder. But it could also be from you rocking it during the draw-down; they don't like agitation during that phase and you could be compacting the finer particles and coarser particles into a mass. Try it w/o rocking it - the fact that the coffee's going south up until that point leads me to think it should finish w/o rocking. I doubt that a stall can lead to an implosion. If you do get a full-blown stall you can wiggle the top very slightly to break the seal at the gasket.