Vacuum pump modification + vacuum science + freeze drying

another thing people miss about vacuums is the need for large diameter piping and it’s explained by another one of this guys videos

and it shows how to get the most out of cheap harbor freight pumps


Very interesting video. I wonder how we can add a larger pipe to a short path kit that could utilize the larger diameter. The traditional cold traps and cow have narrow fittings. So I guess it will not be usable in that regard.

But for vacuum ovens, it totally makes sense.

Have you seen the wide bore setups? People are going all glass to the pump.


Its pretty easy to upgrade to a 1" pipe for the spd. You will need a new cold trap and a few other random pieces of glass, i use all 1" kf25 all the way to thw spd glass. You will need a new and bigger cold trap when you run full bore with pump.

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You may not need a ‘new’ cold trap…find a glass blower and ask him/her to MODIFY your trap! I always think in terms of convenience (being inherently lazy!?), so have in mind joints that are easy to disassemble (ball joints are easier than standard tapers), and keeping all orifices/tubes as wide as possible. If you’re going to be in this business, you will benefit greatly from a healthy relationship with a glass blower!