G’day; Someone was asking about magnetic stirrers. In the '60s
it was almost impossible to get anything slightly unusual in NZ
(including money) - we were very isolated. But the Stage 1
Chemistry lab in the University where I worked needed a dozen
small, slow speed stirrers, urgently. So we managed to get a
dozen little electric clock motors, epoxied small, powerful
alnico magnets to the shaft, and fastened them into small
airtight plastic boxes. Next we found in a toyshop some 1"x1/8"
bar magnets which we sealed into Pyrex glass tube. So, put the
beaker/flask etc on the box, connect to the mains, put the
magnetic follower into the liquid in the vessel - and voila! - a
dozen magnetic stirrers in two days! But we didn’t get thanked;
it was part of the job.
u attached the bars to the clock shafts… do u mean the
clock arms??
– What are ALNIVO magnetic and where would I get them today??
– I’m sure we can come up with the stirring elements per the
people who are selling mag units today
– How fast would the unit turn … RPM…would this be fast
enough for a mag unit as per demo’ed in shows… My guess is
that the RPM is about 60 RPM give or take 20 RPM(COMMENTS …
IF U HAVE SEEN THE UNITS!!!)
- - u attached the bars to the clock shafts... do u mean the
clock arms??
G’day; yes. The motors we bought didn’t have any gearing, and
the shaft rotated at 60 revs per minute; SLOW - don’t confuse
stirrers with magnetic polishers! And they weren’t bars; they
were little cylinders.
-- What are ALNIVO magnetic and where would I get them
today??
Sorry but it’s Alnico; short for aluminium, nickel, cobalt.
Don’t know where you’d get them in the USA; I live on the other
side of the globe. Most tool shops have them here. Modern
ceramic magnets are more powerful. If you can get them – How
fast would the unit turn … RPM…would this be fast enough for
a mag unit as per demo’ed in shows…
As fast as a second hand. I’ve never seen “mag units demo’d in
shows”; shows are like hen’s teeth where I live. Last one I saw
was in Wellington 25 years ago, 200 miles away across two
mountain ranges and a nasty bit of water. We made the magnetic
stirrers which were urgently needed to stir corrosive liquids in
narrow-necked vessels in a University chemistry lab. Because we
couldn’t buy them. Cheers,