Has anybody noticed that Super Glue (cyanoacrylate clear liquid glue) just
doesn't seem to work any more? I remember when it first came out that it
used to bond anything and everything. Lately, seems that I can't even fix my
son's toys with it any more.

Latest failu Just tried to glue a small 12V DC fan for a PA with it and
the bond came apart the next day pretty much by itself.

Al W6LX

Switch to two-part epoxy. You will, however, have to wait for it to set.

"Al Lorona" wrote in message
...
Has anybody noticed that Super Glue (cyanoacrylate clear liquid glue) just
doesn't seem to work any more? I remember when it first came out that it
used to bond anything and everything. Lately, seems that I can't even fix
my
son's toys with it any more.

Latest failu Just tried to glue a small 12V DC fan for a PA with it and
the bond came apart the next day pretty much by itself.

Al W6LX

In article ,
Al Lorona wrote:

Has anybody noticed that Super Glue (cyanoacrylate clear liquid glue) just
doesn't seem to work any more? I remember when it first came out that it
used to bond anything and everything. Lately, seems that I can't even fix my
son's toys with it any more.

Latest failu Just tried to glue a small 12V DC fan for a PA with it and
the bond came apart the next day pretty much by itself.

There are certain specific plastics (polyethylene, polypropylene, and
Teflon) which most cyanoacrylates will not bond to properly (either at
all, or without some specialized surface preparation). I believe that
these plastics are characterized by low surface energy.

If what I read in some of the trade journals is any indication,
manufacturers have been selecting newer and more specialized blends of
thermoplastics and thermoset plastics over the past few years, in
order to optimize the cost, strength, impact resistance, etc. of their
products. It would not surprise me if you're more likely now, than a
few years ago, to run into plastic-resin blends which cyanoacrylates
have difficulty "getting a grip on".

A web page at Saf-t-lok indicates that "Surface ionization
pretreatment is necessary to affect best results with instant bonders
on non-polar plastic surfaces such as polyethylene or polypropylene.
SAF-T-LOK® Surface Conditioner does the job."

Cyanoacrylates also vary significantly in their "grabbing"
aggressiveness, viscosity, gap-filling strength, and their tendency to
bloom (emit the classic eye-searing white fumes which then "frost" the
surface around the application point). My impression is that the
newer non-blooming formulations may not grab as aggressively, or hold
as strongly as the classic variety. None of them seem to be
particularly good in gap-filling strength, unless you add an
additional particulate filler (baking soda is sometime suggested).

Abrading the surface with fine-grit sandpaper, and then degreasing
with isopropyl alcohol, can improve the grip significantly.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

ORIGINAL MESSAGE:

On Tue, 7 Nov 2006 16:31:36 -0800, "Al Lorona"
wrote:

Has anybody noticed that Super Glue (cyanoacrylate clear liquid glue) just
doesn't seem to work any more? I remember when it first came out that it
used to bond anything and everything. Lately, seems that I can't even fix my
son's toys with it any more.

Latest failu Just tried to glue a small 12V DC fan for a PA with it and
the bond came apart the next day pretty much by itself.

Al W6LX




------------ REPLY FOLLOWS ------------

FWIW: Super glue should only be used for temporary fixes. Even though
it may be strong enough when first applied, it gets brittle after
about a year and loses much of its strength.

Bill, W6WRT

Al Lorona wrote:
Has anybody noticed that Super Glue (cyanoacrylate clear liquid glue) just
doesn't seem to work any more? I remember when it first came out that it
used to bond anything and everything. Lately, seems that I can't even fix my
son's toys with it any more.

Latest failu Just tried to glue a small 12V DC fan for a PA with it and
the bond came apart the next day pretty much by itself.

Many modern plastics are not effectively glued with plain old super
glue (Well, for me modern is anything newer than Bakelite). There are
some CA glues that include special activators to help stick to these
plastics but they aren't magic bullets, they turn a failed joint into a
marginal joint.

If you can rough up the surfaces involved (using more area than just
the broken joint) and use a glue that will give a good fillet around
the joint, that'll help. There are thick super glues and epoxies that
help there.

It's very odd that a fan blade would have broken off all by itself.
Usually indicates some sort of mechanical interference (guard loose,
maybe bearings so worn that it's rubbing against something else.)

Tim.

Thank you all for your replies. Tom's treatise on reinforcement was
well-taken on this end and is something I am going to try in the future.

The opinion seems to be that Super Glue has not really changed but that
plastics have changed into a form not as easily repaired by Super Glue.
However, judging from the way Super Glue used to bond my skin vs. how much
less so now, I still suspect that a weakening of the formula may have taken
place, perhaps in response to a lawsuit by someone who accidentally glued
the palm of their hand to the sole of their shoe or something ridiculous
like that. Lawyers are continually ruining products and processes for the
rest of us as they search for the next target from which to extract punitive
damages.

By the way, I never said what kind of failure it was; someone else assumed a
fan blade had cracked. Actually, it was one of the supporting struts that
had cracked. I am fairly confident that with some reinforcement a crack like
this one has a very good chance of being repaired. However, I believe epoxy
is better indicated in this particular case as one of the posters pointed
out. Epoxy is one tough glue.

Thanks again.

Al

"Al Lorona" wrote in message
...
Thank you all for your replies. Tom's treatise on reinforcement was
well-taken on this end and is something I am going to try in the future.

The opinion seems to be that Super Glue has not really changed but that
plastics have changed into a form not as easily repaired by Super Glue.
However, judging from the way Super Glue used to bond my skin vs. how much
less so now, I still suspect that a weakening of the formula may have
taken
place, perhaps in response to a lawsuit by someone who accidentally glued
the palm of their hand to the sole of their shoe or something ridiculous
like that. Lawyers are continually ruining products and processes for the
rest of us as they search for the next target from which to extract
punitive
damages.

By the way, I never said what kind of failure it was; someone else assumed
a
fan blade had cracked. Actually, it was one of the supporting struts that
had cracked. I am fairly confident that with some reinforcement a crack
like
this one has a very good chance of being repaired. However, I believe
epoxy
is better indicated in this particular case as one of the posters pointed
out. Epoxy is one tough glue.

Thanks again.

Al

Al,

You had the best answer. I never seen so much bs in a thread. When the glue
first came out it was not uncommon for the emergency rooms around the
country to have patients with eyes glued shut. Just like the 84 year old
lady who successfully sued McDonalds because of burning her crotch with
their hot coffee. Now they serve their coffee at a lower temperature.
Doesn't taste as good.

Cordially,
west

"west" wrote in message news:r0leh.39$495.3@trnddc06...
You had the best answer. I never seen so much bs in a thread. When the glue
first came out it was not uncommon for the emergency rooms around the
country to have patients with eyes glued shut.

I remember reading the MSDS for super glue many years ago and it specifically
mentioned that it wouldn't actually harm your eye, and the best thing to do
was just wait until the skin naturally dies rather than trying to force open
the lids. Ewwww....

I'm sure it stings like a @#$@ though; just getting my eyes close to the stuff
makes them sting from the fumes.

Just like the 84 year old
lady who successfully sued McDonalds because of burning her crotch with
their hot coffee.

Just to be fair to Ronald, the particular McDonalds in question was serving
their coffee considerably hotter than they own internal guidelines said they
should have been.

Now they serve their coffee at a lower temperature.

Definitely a case of one bad apple (the restaurant) ruining it for everyone.

"Joel Kolstad" wrote in message
...
"west" wrote in message
news:r0leh.39$495.3@trnddc06...


Just to be fair to Ronald, the particular McDonalds in question was
serving their coffee considerably hotter than they own internal guidelines
said they should have been.

Now they serve their coffee at a lower temperature.

Definitely a case of one bad apple (the restaurant) ruining it for
everyone.


Didn't ruin it for everyone, my Mom had already taken care of coffee for me.
She sneaked a dose of castor oil into a cup of coffee to trick me into
drinking it when I was seven years old.
That's the last cup of coffee I ever had. I still detect a slight tinge of
castor oil when I smell coffee cooking.(G) Waagh! I'm just glad she didn't
find a way to spoil the smell of gunsmoke for me.

HWB

ORIGINAL MESSAGE:

On Fri, 08 Dec 2006 21:43:51 GMT, "west" wrote:


Now they serve their coffee at a lower temperature.
Doesn't taste as good.

------------ REPLY FOLLOWS ------------

But you don't have to eat that hospital food either. :-)

Bill, W6WRT