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lynnl
10-14-2010, 11:51 AM
Do anerobic adhesives such as Loctite work in wood, or other porous materials? e.g. permanently fixing a bolt or screw in wood?

Or would epoxy be a better choice?

Evan
10-14-2010, 11:56 AM
No, they will not work. Oxygen isn't the only problem. The resins in wood inactivate many of the cyano adhesives so they must be formulated for wood. Epoxy is the best choice.

lynnl
10-14-2010, 11:58 AM
Drat! I was afraid of that.

Thanks Evan.

MuellerNick
10-14-2010, 01:29 PM
Do anerobic adhesives such as Loctite work in wood

WHAT Loctite? The ones for metal do not work.
But CA ("super glue") works great on wood. Ask a model builder ...
Sometimes they don't want to react, then use zipper (an activator).


Nick

Evan
10-14-2010, 01:39 PM
There are many types of cyanoacrylates. Some work with wood and some don't. Loctite thread lockers are based on cyanoacrylates too but definitely don't work with wood. One way to make most cyanoacrylates polymerize instantly is to prime the surface with sodium bicarbonate powder. It can also be used to build up a fillet of dry powder which you then soak with very low viscosity CA glue such as ZAP.

Warning: If you use the sodium bicarbonate trick the glue will go off IMMEDIATELY. It will release a considerable amount of noxious fumes so be sure to have the airflow away from your face.

MuellerNick
10-14-2010, 02:09 PM
Loctite thread lockers are based on cyanoacrylates too but definitely don't work with wood.

I think I wrote that it doesn't work with thread lockers (= for metals). But they are not CA-glues.
I also think I wrote "super clue", and that clearly works with wood. What is commonly called CA reacts with water.
Loctite for metal is an modified anaerobic glue that needs metal to cure.


But you only had to contradict ...

Nick

Evan
10-14-2010, 02:33 PM
I think I wrote that it doesn't work with thread lockers (= for metals). But they are not CA-glues.
I also think I wrote "super clue", and that clearly works with wood. What is commonly called CA reacts with water.
Loctite for metal is an modified anaerobic glue that needs metal to cure.


But you only had to contradict ...


Not contradicting, correcting.

Superglue is a Brand, not a specific glue.

Cyanoacrylate glues are catalysed by bases, not water. Most surfaces tend to be basic and water mobilizes those ions. Why don't you try it instead of shooting off your mouth? Woods are usually acidic and prevent catalysis.

Loctite is also a brand, not a specific product. The Loctite thread locking compounds are based on a modified cyanoacrylate formula, usually polyglycol methacrylate. Metal is not the catalyst. Oxygen acts as an inhibitor for thread lockers. When they are out of contact with oxygen the reaction is able to proceed.

So far you are batting zero. Care to make any other mistakes today?

MotorradMike
10-14-2010, 02:55 PM
So far you are batting zero. Care to make any other mistakes today?

Why do you have to be like that?

MuellerNick
10-14-2010, 03:02 PM
Superglue is a Brand, not a specific glue.


IDIOT!
I wrote CA ("super glue") I wrote both the brand an the common denominator. Now you ASSHOLE FROM OUTER SPACE have nothing more to do than just pick out what suits your three rotten neural cells to start just another useless discussion.


The Loctite thread locking compounds are based on a modified cyanoacrylate formula, usually polyglycol methacrylate.

YOU ARE SO DUMB THAT IT HURTS!
CA stands for methyl 2-cyanoacrylate, ethyl-2-cyanoacrylate, n-butyl cyanoacrylate, 2-octyl cyanoacrylate. CYANOxxx! Not methylxxx. The C in CA! methacrylate lacks the CN (= cyan)



PISS OFF AND ADJUST YOUR FILTER!


Nick

ikdor
10-14-2010, 03:05 PM
The Loctite thread locking compounds are based on a modified cyanoacrylate formula, usually polyglycol methacrylate. Metal is not the catalyst. Oxygen acts as an inhibitor for thread lockers. When they are out of contact with oxygen the reaction is able to proceed.

Well, this is just not true, otherwise it would solidify in the bottle. It needs the metal AND the lack of oxygen.

Directly from the site of Permabond:
"By definition, anaerobic adhesives remain liquid until isolated from oxygen in the presence of metal ions, such as iron or copper."

Igor

wierdscience
10-14-2010, 03:09 PM
Loctite 271 will hit on wood,I learned that the hard way once.Have no clue as to how long it takes to cure thou.

On wood though I use plain vanilla $.99/2-pack super glue since it's one hell of a lot cheaper.

Evan
10-14-2010, 03:15 PM
Why do you have to be like that?


Because that is how Nick is.


Well, this is just not true, otherwise it would solidify in the bottle. It needs the metal AND the lack of oxygen.

The container contains an inhibitor.

Metals will promote a faster cure but it will still cure when not in contact with active metals.


YOU ARE SO DUMB THAT IT HURTS!




Look up the word MODIFIED
Have you tried the bicarbonate trick yet dickhead?

I have to go to town in a few minutes. Later.

MuellerNick
10-14-2010, 03:22 PM
Look up the word MODIFIED

Yes, modified. Now it is something new. But for the no-brainer it is still the same. Just a new name. CA.
Polyvinyl is just a modified polygon. It starts with poly, so it must be just modified.



Have you tried the bicarbonate trick yet dickhead?

No, I see at you that it seems to be a neural toxic.


Nick

MuellerNick
10-14-2010, 03:24 PM
I'm asking a mod to close this thread before I freak out with that dumbass Evan!

Thanks,
Nick

gwilson
10-14-2010, 03:30 PM
I understand that the package that Loctite comes in is permeable by oxygen,which keeps the loctite from hardening up,and limits its shelf life to 6 months.

I'm no expert on this,but that's what I was told.

Evan certainly isn't stupid,either.

ikdor
10-14-2010, 03:38 PM
The container contains an inhibitor.

Metals will promote a faster cure but it will still cure when not in contact with active metals.


I looked it up in the 3M anaerobics FAQ and actually the air in the bottle is the inhibitor. I didn't expect that as I assumed the fluid at the bottom would be oxygen starved by the lack of stirring in storage. The bottle itself is permeable to oxygen to make sure there is always a fresh supply.

Well, at least I learned something in between all the name calling.

Igor

gwilson
10-14-2010, 03:43 PM
Seems to be some hostility between Evan and Nick!!

john b
10-14-2010, 03:59 PM
According to LOCTITE MSDS there is no CA in the thread lockers. John b.

jdunmyer
10-14-2010, 04:13 PM
There was an article several years ago in one of "our" magazines that explained how LocTite et. al. worked, and it explained how they interacted with the metal somehow and would not work with other materials.

Liger Zero
10-14-2010, 04:33 PM
Um.

Unofficial Moderator Hat = On.

MuellerNick: Cool your jets. It's ok to disagree, it's ok to point out that someone is wrong. Attack the idea, not the person.

Evan: Back off and don't respond to MuellerNick otherwise we'll be at this all night.

Moderator Hat = Off


This is from Wiki




Cyanoacrylate is the generic name for cyanoacrylate based fast-acting adhesives (http://en.wikipedia.org/wiki/Adhesive) such as methyl 2-cyanoacrylate (http://en.wikipedia.org/wiki/Methyl_cyanoacrylate), ethyl-2-cyanoacrylate (http://en.wikipedia.org/wiki/Ethyl_cyanoacrylate) (commonly sold under trade names like SuperGlue and Krazy Glue), and n-butyl cyanoacrylate (http://en.wikipedia.org/wiki/Butyl_cyanoacrylate) (used in the veterinary glues Vetbond and LiquiVet and skin glues like Xoin, Indermil and Histoacryl). 2-octyl cyanoacrylate (http://en.wikipedia.org/wiki/2-Octyl_cyanoacrylate) is a medical grade glue encountered under various trade names (http://en.wikipedia.org/wiki/Trade_name); e.g., LiquiBand, SurgiSeal, FloraSeal, Dermabond, Orabase, Surgi-Lock and Nexaband. This was developed to be non-toxic and less irritating to skin tissue. Cyanoacrylate adhesives are sometimes known as "instant glues". The abbreviation "CA" is commonly used for industrial grades.




More from Wiki:




In its liquid form, cyanoacrylate consists of monomers (http://en.wikipedia.org/wiki/Monomer) of cyanoacrylate molecules. Methyl-2-cyanoacrylate (CH2=C(CN)COOCH3 or C5H5NO2) has a molecular weight equal to 111.1, a flashpoint (http://en.wikipedia.org/wiki/Flashpoint) of 79 °C, and 1.1 times the density of water (http://en.wikipedia.org/wiki/Water_%28molecule%29).[citation needed (http://en.wikipedia.org/wiki/Wikipedia:Citation_needed)] Ethyl-2-cyanoacrylate (C6H7NO2) has a molecular weight equal to 125 and a flashpoint of >75°C. To facilitate easy handling, a cyanoacrylate adhesive is frequently formulated with an ingredient such as fumed silica (http://en.wikipedia.org/wiki/Fumed_silica) to make it more viscous (http://en.wikipedia.org/wiki/Viscous) or gel-like.
Generally, cyanoacrylate is an acrylic (http://en.wikipedia.org/wiki/Acryl_group) resin (http://en.wikipedia.org/wiki/Resin) which rapidly polymerises (http://en.wikipedia.org/wiki/Polymer) in the presence of water (specifically hydroxide (http://en.wikipedia.org/wiki/Hydroxide) ions (http://en.wikipedia.org/wiki/Ion)), forming long, strong chains, joining the bonded surfaces together. Because the presence of moisture causes the glue to set, exposure to moisture in the air can cause a tube or bottle of glue to become unusable over time. To prevent an opened container of glue from setting before use, it must be stored in an airtight jar or bottle with a package of silica gel (http://en.wikipedia.org/wiki/Silica_gel).







As a Polymer Dude, I can tell you that there is more than one form of "super glue..." each based on a different molecule and catalyst agent. This means different reaction triggers.


Some forms are more common than others.

topct
10-14-2010, 04:37 PM
I worked on a motorcycle that the owner had "lubricated" his already well oiled chain with some green colored locktite. I can assure everyone that the locktite did not not make contact with the metal of that chain. And it seemed to have cured just fine.

MuellerNick
10-14-2010, 04:39 PM
Seems to be some hostility between Evan and Nick!!


Well, look, it is that way:
I hate it when people tell nonsense. Especially when that nonsense is disguised with sci-blabla. Modified CA! That's how Evan tries to come out of that. He will search so long until he finds a site that calls methacrylate a modified cyanoacrylate. It doesn't matter that the producer calls it anaerobic and doesn't speak any word about CA (in thread lockers). It is Evan's universe, warped, bent, distorted. But always right!

All that once more started with a very simple and correct answer by me. There is absolutely nothing wrong with what I said.

It's the same **** with the bearing steels. He googled until he found that xxx1000 steel, a carbonizing steel where he pretended that it is used for ball bearings. That is a fraction of the truth! First of all, it is a case hardening steel for gears. In some cases, it is used for spindles that do have a ball race. But he just left that out to make him look clever.
When have you last seen a lathe spindle with the race directly ground on it?

Now watch for this drama to go over 10 pages ...

Nick

MuellerNick
10-14-2010, 04:50 PM
MuellerNick: Cool your jets. It's ok to disagree, it's ok to point out that someone is wrong. Attack the idea, not the person.


You should direct that at Evan. He once more was the one who started it. Read from the beginning. Read what Evan wrongly told just to contradict me.

Patterns repeating ...


Nick

KIMFAB
10-14-2010, 04:51 PM
Evan and Nick
Thanks, You provided my amusement for the day.
Those are PM quality rantings.

Liger Zero
10-14-2010, 04:54 PM
The relevent facts here are:

Some CA adhesives are triggered by bases, others by oxygen, some by water.

Commercial "super glue" consists of a blend of the various CAs.

methacrylate and MCA are two different compounds. It is possible to have a Methyl cyanoacrylate or a Ethyl cyanoacrylate.

Polymer chemistry is confusing even to people who study it. At the end of the day I rely on my textbooks and Wiki to keep it all in line. Hell I've been doing this for a LONG time and I still get Homo and Co polymer mixed up when it comes to Delrin and Generics Acetal. :)

Liger Zero
10-14-2010, 04:59 PM
IDIOT!

ASSHOLE FROM OUTER SPACE



YOU ARE SO DUMB THAT IT HURTS!



PISS OFF AND ADJUST YOUR FILTER!


Nick



Compared to:



So far you are batting zero. Care to make any other mistakes today?




Evan is wrong for phrasing his retort that way. YOU are wrong for escalating it. HE is wrong continuing to escalate it... and YOU are wrong for continuing as well.


BOTH of you need to cool the heck off. :)

MuellerNick
10-14-2010, 05:00 PM
Just two quotes from Evan:


Metal is not the catalyst


Metals will promote a faster cure but it will still cure when not in contact with active metals.

Now what?
Care to ask Loctite why it works so bad with brass? Well, that still is a metal, but not active enough.
And a glue that takes 1/2 a year to cure, is that still called a glue? Or is that just a Oh-it-works-I'm-Evan-glue?

O-rings for transmitting power do work too, you just have to discuss with Evan. :D



Nick

beanbag
10-14-2010, 05:02 PM
Woods are usually acidic and prevent catalysis.


This explains why my experiment using wood backing and superglue was a failure. If I dampened the wood with water and baking soda, would it work?

Superglue also seems to work poorly on SS?

Liger Zero
10-14-2010, 05:07 PM
Care to ask Loctite why it works so bad with brass? Well, that still is a metal, but not active enough.


Make sure the brass is clean. If that doesn't help, kiss the area to be glued with a propane-torch flame. If it doesn't work then, troubleshoot the glue.



And a glue that takes 1/2 a year to cure, is that still called a glue? Or is that just a Oh-it-works-I'm-Evan-glue?


Use a kicker, or discard the glue as there is a problem somewhere.

MuellerNick
10-14-2010, 05:12 PM
Make sure the brass is clean. If that doesn't help, kiss the area to be glued with a propane-torch flame. If it doesn't work then, troubleshoot the glue.

I won't look for the original answer from Loctite. But it was that brass is not very reactive. It can be fixed with a longer curing time, temperature, ...
The point is, that the metal plays a HUGE rule in the curing.
And not as Evan ... blablabla ... page 10 ... blablabla ... page 30 ... blablabla ...


Nick

Liger Zero
10-14-2010, 05:16 PM
It is possible that the adhesives manufactured by Loctite are tweaked to react with metal, metal ions or some other facet of metal chemistry.

It could boil down to we are comparing two different classes of "super glue" and that is why we are coming up with different answers.

saltmine
10-14-2010, 05:29 PM
"Green colored" Loctite is commonly known as Loctite 680, or "sleeve lock"
It has a variety of uses, but is usually found in diesel repair shops for locking "wet" sleeves in large diesel engines. I have some, but don't like to use it because it almost takes an "act of God" to separate the parts after the 680 has cured.

I was curious as to the title of this thread, "Anerobic adhesives"

It was my understanding that any chemical or chemical compound that is "anerobic" usually cures in the absence of air (or oxygen). When I worked as a mechanic, we used a thick, almost purple sealer, Loctite 518 (made by Loctite) which cured when air was removed. Wonderful stuff, we used it mainly where two machined castings came together, and you didn't want a dimensional change due to the sealer, like transfer case halves and transmission maincases. The nice thing about it is the fact that it didn't cure until the parts were properly positioned, and torqued.

For the past 45 years, I've been a frequent user of almost all types of adhesives and sealers. It still amazes me, to this day, how little people in the industry know about basic sealers and adhesives.

MuellerNick
10-14-2010, 05:40 PM
It is possible that the adhesives manufactured by Loctite are tweaked to react with metal, metal ions or some other facet of metal chemistry.

That's a fact, not just possible. As long as we speak about their metal glues.


It could boil down to we are comparing two different classes of "super glue" and that is why we are coming up with different answers.


"Super glue" = CA. Thread locker != CA. Can't be boiled down to more.
Even Evan said that thread lock is not cyanoacrylate. It just takes longer for him to realize that. :D



Nick

MuellerNick
10-14-2010, 05:43 PM
"Anerobic adhesives"

It is called "anaerobic". Might help when googling to separate the BS from the facts. ;)


Nick

Boucher
10-14-2010, 06:05 PM
Loctite sells a cleaner--primer that will activate it in locations that it would not normally cure in. Best I can remember it was recommended in non ferrous applications like Alumium. Regarding shelf life. I am still using some that I have had for 20+ years.

PixMan
10-14-2010, 06:29 PM
Before I post anything, here's my qualifications to add to this thread: None. I am a dumbass jerk and know nothing about chemistry, adhesives, scientific terms, nothing. OK?

I have a bottle of LoctiteŽ 324 Adhesive and Activator 7075 that I was given upon leaving Norton/TRW Ceramics. We used it to "glue" cold-rolled steel ends onto SiAlON (ceramic) engine valves. After gluing the steel end onto the ceramic valves, we would drill center holes and grind them to size on an Okuma or Konda CNC cylindrical grinder. That my friends is a LOT of force in shearing, and the adhesive held up fine until we used a propane torch to melt the ends off.

At a job I later went to, I had a wooden-handled large screwdriver that a coworker thought would work well as a cold chisel. He broke the handle almost in half. I sprayed each half with the 7075 Activator, then coated one side with a layer of the 324 adhesive. 18 years later, it's still in one piece. Mind you, both pieces of that wood were dirty and oily.

I have also used it to glue together the temple/hinge of my Nikon sunglasses that my older son sat on. It worked fine, but I have to be careful because it did come apart once when I whipped them open. It's a very small patch of adhesive, after all.

mototed
10-14-2010, 06:40 PM
Back to the OP, I think an epoxy or maybe a plain old wood glue may work.
There is an epoxy that they use on wooden axe (sledge, hammer , etc.) handles to head connections. That's about as strong as you can get with wood! Beats the little wedge expanders.
I ran out of wood glue one day and grabbed a tube of RTV sealant for a wood to wood connection. A few years later when I took this project apart, the RTV glued joints ripped deep into wood fibers when beat / pried apart.
Ted

interrupted_cut
10-14-2010, 06:54 PM
The idea that the Loctite bottles were air permeable to prevent setting of the material is interesting. I have many bottles of various grades of Loctite of varying vintage, and I notice that the older bottles "sweat" their contents out onto the surface of the container, often lifting and obliterating the labeling. This has always been a puzzle to me.
One of the side benefits of working around the aerospace industry is they throw away a ton of adhesives and sealants that have passed a somewhat arbitrary shelf life date. They still seem to work fine for home and car use for years afterwards. On a sillier note, a Hughes Aircraft plant I worked at in the early 80's got shut down for a week due to an Air Force auditor finding a bottle of CA glue in the product test area without a "use by" date sticker. We used the CA to glue accelerometers on the parts before we put them in an environmental chamber for a 24 hour "shake 'n bake", and then snapped the accels off afterwards. I'm sure he thought it was worth over a million $$ to make sure we used certified glue for that!
My experience with CA glue and wood is that it often cures extremely rapidly when it soaks into the grain, sometimes releasing noxious fumes and getting quite hot, even in the absence of "zip kicker" catalyst or baking soda. I know woodworkers use lots of CA glue to hold together exotic woods and burls during fine turning.

Evan
10-14-2010, 07:22 PM
Before Nick went off the deep end (as usual) I posted:

"The Loctite thread locking compounds are based on a modified cyanoacrylate formula, usually polyglycol methacrylate."

Here is an example:

http://ixian.ca/pics7/tlock.jpg

Nick is a stalker. He is full of BS and has the manners of a goat. He has been disrupting this forum since he first signed on.

gaston
10-14-2010, 07:38 PM
WAHOO!!! more pissin up the barn wall! I'll bet Evan can pee higher than Nick
:)

Evan
10-14-2010, 07:43 PM
I'm busy tonight. I am working on herringbone gears using my version of the "new" cutting method.

gwilson
10-14-2010, 08:41 PM
I have had OLD Loctite,too. The official word is that it has a 6 month shelf life,though. That apparently doesn't always mean the stuff has gone bad.

Are you guys aware that there is a grade of Loctite that is used to glue the barrels of double barreled shot guns together instead of solder? 660,I think. My friend Jon,a gunsmith, my former journeyman uses it for that purpose.

Black_Moons
10-14-2010, 08:57 PM
I'm busy tonight. I am working on herringbone gears using my version of the "new" cutting method.

Ah finaly, something worthwhile outta this thread. Apon googleing herringbone gears I learned they are basicly two spiral gears back to back, with opposite spirals. Very cool! Helical gears without the thrust forces.

Also apon the page I learned that, I saw a really cool gear that blew my mind: http://www.monarchbearing.com/images/spiral-bevel-gears.jpg
Spiral bevel gears.. Crazy, just crazy.

PS: on that page I found the pic ( http://www.monarchbearing.com/gears.html ) it mentions Bevel gears and Miter gears.. Whats the diffrence?

Deja Vu
10-14-2010, 09:27 PM
Ah finaly, something worthwhile outta this thread. Apon googleing herringbone gears I learned they are basicly two spiral gears back to back, with opposite spirals. Very cool! Helical gears without the thrust forces.

Also apon the page I learned that, I saw a really cool gear that blew my mind: http://www.monarchbearing.com/images/spiral-bevel-gears.jpg
Spiral bevel gears.. Crazy, just crazy.

PS: on that page I found the pic ( http://www.monarchbearing.com/gears.html ) it mentions Bevel gears and Miter gears.. Whats the diffrence?

Just a little somethin' extra here.
Testing a machinist's herringbone gear creation. If you're looking for it to crash....it doesn't happen. But there is an inspection of the gear at the end of the long video. Enjoy!
http://www.youtube.com/watch?v=gZlb9-YctfE

lynnl
10-14-2010, 09:36 PM
Back to the OP, I think an epoxy or maybe a plain old wood glue may work.
There is an epoxy that they use on wooden axe (sledge, hammer , etc.) handles to head connections. That's about as strong as you can get with wood! Beats the little wedge expanders.


I've had a few yard tools with the handles embedded in that stuff, and have lusted for some of it. Anybody know where or how that it can be obtained?

As for my original question, I didn't word it specifically enough. What I had in mind was the threadlocker adhesive, whether by Loctite or other makers. I think I have some by Permatex, as well as Loctite 271 (I think is the no.; it's red anyway.) Also got a tube recently at HF, but haven't tried it yet.

I'm now thinking maybe some of the polyurethane glue, like Gorilla Glue, might serve my purpose. I think I've used it to bond rubber to aluminum before.

What I'm needing to do is ensure some threaded inserts don't unscrew from the wood due to anticipated pretty forceful unscrewing torque. Probably don't need any extreme adhesion, but I like to be sure when possible.

As for shelf life I'll say this, stored in the refrigerator that Loctite 271 (or whatever it is) tube is several years old, and it seems as effective as ever.

Deja Vu
10-14-2010, 09:57 PM
As for shelf life I'll say this, stored in the refrigerator that Loctite 271 (or whatever it is) tube is several years old, and it seems as effective as ever.

Heh! I've got some Loctite 2114 that i've had for years and it still Lock's 'n Seals. ;) But some other adhesives around here are going to be set before I get the dispenser empty.:(

becksmachine
10-14-2010, 10:14 PM
PS: on that page I found the pic ( http://www.monarchbearing.com/gears.html ) it mentions Bevel gears and Miter gears.. Whats the diffrence?

I think "miter gears" implies going around a corner at a 1-1 ratio, whereas "bevel gears" also go around a corner but with some ratio other than 1-1.

Dave

ckelloug
10-14-2010, 10:37 PM
Evan,

Regarding, your post #7, have you ever heard of the concept of pOH or pH for that matter. I'll give you a hint: pOH is the concentration of hydroxyl ions in a solution. Water always disassociates to a slight extent so there are always a few hydroxyl ions in water.

Thus we can intuit that given enough time, atmospheric humidity will catalyze ordinary CA ("superglue").

Everyone can read in the attached patent in the words of the inventor, Harold Coover, the fact that Cyanoacrylate glues are catalyzed by hydroxyl ions. See http://www.freepatentsonline.com/2768109.pdf

We know from chemistry that the pOH of a solution increases when you add bases to water. This is why superglue can by catalyzed with baking soda. It also points out in the patent that standard CA adhesives are preserved by adding a very small amount of acid. The glue won't set unless that added acid is overcome by either a basic accelerator, another source of hydroxyl ions like atmospheric humidity, or unexpectedly alcohol.

The interesting thing in the patent and one which I had not known is that short chain alkane alcohols also catalyze the curing reaction. The patent says they catalyze it more slowly than strong bases (like NaOH) which can cause weak bonds when the CA cures too fast.

Translating from chemspeak, wipe the parts to be bonded with either methyl alcohol (shellac thinner), ethyl alcohol (moonshine), or isopropyl alcohol (disinfectant rubbing alcohol) and let it dry for a moment. Position the parts and add the glue and the residual alcohol will catalyze the CA setting in reasonable time.

While there are a large number of CA glues on the market with different amounts of acid inhibitor, different plasticizers etc, (Different R groups attached to the cyanoacrylate group) they all work by polymerization of the cyanoacrylate group which is catalyzed by hydroxyl ions and alcohols.

A modified cyanoacrylate is one that has had plasticizers, viscosity modifiers etc. added and or perhaps some strange R-groups outside the ones Nick has listed. It has nothing to do with the setting mechanism of the cyanoacrylate itself which is still polymerization of the cyanoacrylate groups which are still catalyzed by hydroxyl ions or alcohols.

Examining the MSDS for the loctite anerobic threadlocks 290, 242, and 271, they use polyglycol dimethacrylate, not cyanoacrylate. I have to conclude setting is initiated by the decomposition of Cumene Hydroperoxide into Cumyl alcohol which is initiated by metal ions and acids. As near as I can tell, the small amounts of saccharin and N,N, diakyltoluidines present keep the solution slightly basic to prevent the decomposition of the cumene hydroperoxide but not basic enough to catalyze polymerization. Apparently, the polyglycol dimethacrylate is resistant to a weakly basic environment. I predict that a strong base like NaOH however would cause these threadlocks to set via a hydroxyl catalyzed reaction mechanism.

Summary: Cyanoacrylate adhesives cure in the presence of basic chemicals or, unexpectedly as explained in Coover's patent, alcohols. If you are trying to use Cyanoacrylates, Coover's patent shows that alcohol will make it set on just about any surface, even acidic surfaces like green wood. Alcohol on the surface of the part to be bonded will make ordinary CA polymerize. While anaerobic threadlocks are not cyanoacrylates, from the chemistry, it's likely that alocohol will also make the anaerobic threadlocks polymerize since decomposition of cumene hydroperoxide produces cumyl alcohol. A strong base is also likely to polymerize the thread locks though they are not polymerized by a weak base like CA superglues.

--Cameron

wierdscience
10-14-2010, 10:57 PM
Excellent post Cameron,answered a lot of questions I had on the subject.

In my case the 271 was spilled in my toolbox unknown to me and dripped between the edges of an oak tool case that I had refinished with Shellac about three months before the spill.It set and set hard.I figure it happened only a day before I noticed the drip.

I wonder if the 271 kicked because of being exposed to atmospheric humidity or because of the alcohol residual in the Shellac or a combination of both?

Dragons_fire
10-14-2010, 11:16 PM
Also apon the page I learned that, I saw a really cool gear that blew my mind: http://www.monarchbearing.com/images/spiral-bevel-gears.jpg
Spiral bevel gears.. Crazy, just crazy.


dont mean to hijack the crazyness... But the spiral bevel gears is how most car and truck ring and pinion gears in the axles are cut....

Black_Moons
10-15-2010, 12:22 AM
dont mean to hijack the crazyness... But the spiral bevel gears is how most car and truck ring and pinion gears in the axles are cut....

I try really hard not to take apart my truck -_-;

MuellerNick
10-15-2010, 04:14 AM
"The Loctite thread locking compounds are based on a modified cyanoacrylate formula, usually polyglycol methacrylate."

Here is an example:

You are so predictable! I knew that you will google until you find one that has CA in his thread locker.


It doesn't matter that you contradict yourself. When in fact the data you googled up shows that this specific thread locker has both cyanoacrylate and methacrylate in it. So your thread locker is neither out of "usually methacrylate" nor out of "modified cyanoacrylate". It is made of both.

It's called googledge ("knowledge" by google). Same like with the ball bearing steel.

Patterns repeat.