HI harry

Harry Bloomfield wrote:
Adrian wrote on 04/12/2008 :

At the moment, I've got a couple of mains-operated ec-computer fans
mounted through the timber walls, sucking fumes out from the studio.
Trouble is, they're about 12" away from where the actual soldering is
done, there's not as much 'suck' (!) as I'd like... and they're pretty
noisy when running.

If they are only 12" away, then I would expect them to be fairly
effective at drawing the fumes out. Probably the problem is the distance
they are from the source of the fumes and the fact that hot fumes tend
to rise vertically.

That's a possibility...


Might you not be better with some sort of funnel to collect the fumes,
directly over where you are working? The idea should be to the fumes
away at their source, rather drawing out air after the fumes have mixed
with lots of it.

That's what I was thinking of with the 'extractor fan and 4" hose' idea....

Trouble with a 'hood' arrangement (like a fume cupboard) is that there
are times when you have to be 'above' the work being soldered, rather
than working at arms length as in a fume cupboard - so if you're
extracting via a hood then the fumes have to go past you to get to the
extract system g - which isn't ideal...




Those 12v PC fans are not really that effective, much better would be
the 6" or 8" 240v operated fans intended for main frame computers. You
can get these from electronic surplus dealers for a pound or two and
they will keep going for many years. Google for Bull electronic surplus,
as one possible source.


I thougt I said in the original post that these are mains fans (of
unknown parentage - but they're a good bit more effective than the 12V
PC 'air stirrers').

The other issue is noise level - as I like music playing while I'm
working, and with the existing fans running flat out the music has to be
turned up really loud.... so the idea was to mount the noisy fans
_outside_ the studio and just have the ducting inside - don;t know how
much this might reduce the noise. The Studio is timber-built - so maybe
some sort of mechanical isolation of the fans would reduce the noise
(the existing ones are probably 25 years old -so the bearings are likely
shot!)

Another plan is to arrange some sort of mechanical switchery - so that
lifting the iron off its stand causes the fans to start up - or even go
from 'idle' to 'max'.... but that's phase 2 of the scheme!

Thanks
Adrian