if the engineer does not know the specs, you got the wrong one for
You need an air conditioning engineer. It sounds like the fumes have
a long way to travel and a powerful fan would be needed. Also the
bends in the pipe will slow down airflow. Also if you use the
flexible ducting it slows down air flow and traps dust.
How noisy/annoying will the fan get? You will need kill switches for
the fan in case a fire starts. One on the soldering bench and one on
the exit door.
How will you store chemicals and will there be fumes from them?
How will you get fresh air into the basement? It is good to remove
toxic fumes but you need clean air coming in.
These are questions an air conditioning engineer can answer for you
and tell you how to get the job done.
As you are building a metal workshop the air con. engineer can
design the fume hood and it can be made out of galvanised tin with
very basic tools like drills and rivets and silastic sealer. The
metal dealer would cut your pattern and you would just have to
rivet/bolt the sections together and bolt to the wall. And save some
money for metals and stones.
It will be difficult to set up a workshop in a basement, but hey
I’ve seen NCIS that guy builds boats in his basement.
Now we on Orchid can’t wait to see what the students make, they
should all join Orchid
All the best any questions, I teach jewellery at a not for profit
school, email me off line for any info you need.