I have never worked with vacuum systems (other than as an
observer), and need some advice to get me started.

I have a Welch 1402 Duo-Seal vacuum pump, which has been
sitting in storage for at least five years. I have not
yet tried to use it, just in case there is something critical
I need to do first. I got it from a going-out-of-business
surplus store, so I don't know its history.

I have never worked with vacuum systems (other than as an
observer), and need some advice to get me started.

I have a Welch 1402 Duo-Seal vacuum pump, which has been
sitting in storage for at least five years. I have not
yet tried to use it, just in case there is something critical
I need to do first. I got it from a going-out-of-business
surplus store, so I don't know its history.

I also have a bell jar, about 9" I.D. and 9" inside height.
It has two ground-glass openings, at the top, and on the
side near the bottom. The top one tapers from about 1.5"
down to about 1.25", and the side one tapers from about
1.2" down to about 1". It came with a chipboard base with
a 1/8" rubber sheet on top for a seal.

I have nothing else yet, so my first question is where to
buy the bits and pieces I need to complete the system. I
live in Los Angeles, so local places would be appreciated.
Since this is for (mostly) hobby use, low prices are even
more appreciated! :-)

Things I know I will need are: vacuum tubing, fittings for
the bell jar, vacuum grease, etc. What kind of tubing
should I get, and how do I connect it to the ground-glass
openings on the bell jar? Some kind or rubber stopper?


My first project is not very demanding: to vacuum-dry some
computer backup tapes that will be exposed to high temperature
and humidity while testing a new fire safe design.

The research I have done so far indicates that I need to
install a dry-ice cold trap in the line if there is moisture
present. I am assuming that drying these tapes qualifies.
Is it reasonable for me to build my own from, say, copper
pipe? Does anyone have a suggested design? I was thinking
of just a loop of large copper pipe immersed in an insulated
container of dry ice and alcohol.

Future projects might include neon lights or even a gas laser.

Is there anything I should do before turning the vacuum pump
on for the first time?

What questions should I be asking at this point?

Are there any books or online sources of information that
I should be reading?

Any advice would be greatly appreciated!

Thanks,
Alan Remove "_REMOVE" from e-mail address to reply.