"William Noble" wrote in message
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"Dave Martindale" wrote in message
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"Michael Koblic" writes:

1) How does a $14-threadlocker differ from a $2 Superglue? I gather the
threadlockers are anaerobic. Does that mean that superglue is aerobic?

Cyanoacrylate (super glue) sets on contact with water vapour in the air
(or on your skin, if applied there). It's stored in a container that is
sealed to prevent contact with the air.

Threadlockers are weird plastics that remain liquid as long as they are
in contact with oxygen. They are stored in bottles that are permeable
to oxygen, and which have a significant air space above the liquid.
They set only when you isolate them from oxygen, such as in the space
between a bolt and nut thread.

Dave

no, the above statement about superglue is just plain wrong - it does NOT
cure upon contact with moisture in the air - you are thinking of Silicone
rubber - I use superglue on woodturning projects (some examples might be
seen in the gallery on my web page or at www.woodturners.org) - and I keep
the bottle in my shop, open to the air - the current 1 pint bottle has
been there for 3 years and it has not hardened up. What makes it harden
up is lack of air and contact with a foreign substance - in particular
there is something in the fungus that gets into wood that really catalyzes
the reaction - but for sure it isn't moisture.

Something is getting misconscrewed here, William. Cyanoacrylate glues
("superglue") are generally moisture-cure, aerobic adhesives. The acrylic
adhesives used in the standard varietes of Loctite and competing
thread-lockers are acrylic adhesives formulated to be anaerobic-curing.

I don't know if it's possible to make an anaerobic cyanoacrylate, but maybe
so. That's not what you buy in the hardware stores, though.

Dave's description is correct. I spent a day at Loctite's headquarters many
years ago going over exactly this subject with them, researching a 12-page
American Machinist Special Report on adhesive assembly in metalworking.
Those little plastic vials that Loctite comes in are porous to oxygen.

--
Ed Huntress