Does CA become rotten?

[soholingo]

I have a bottle of thin ca that doesn't have a cap. I used a bit today and it just wouldn't cure. it took about 10 minutes before it cured partially. I then just used a fresh bottle of thick ca and it held quickly. Is the thin CA rotten?

oh and where is the best place/ best brand of CA?

Jay

[davidfee]

Yes. It absorbs moisture from the air, making it "rotten." Eventually, the whole bottle will be a solid chunk. CA cures by a polymerization reaction initiated by the presence of water. I knew my degree in chemistry would be useful someday. ;)

There is water on nearly all surfaces and your body is like 80% water, which is why you can glue your fingers together faster than two sticks of balsa. ;)

See here for an article on the chemistry:
http://voh.chem.ucla.edu/vohtar/spring00/30H/pdf/Brubaker.pdf

All brands of CA go bad before I can use the bottle up, so I buy the cheap house-brand at Hobby People, or the very smallest bottles of ZAP brand.

-David

[soholingo]

this is good to know as I am about to start the repair on the stratos... and we can't have rotten CA now can we?

[davidfee]

Oh yeah, and if anyone ever tells you to use CA "because it's light," tell them that CA absorbs water from the air and materials being bonded during the curing process. This means CA actually gets heavier as it cures. Other solvent-based (including water-based) glues get lighter as they dry... so they are a better choice when light weight is the goal.

Epoxy is not heavy... too much epoxy is. :)

-David

[soholingo]

Thanks for the input Dave, I must remember to pick some CA and sugar up this evening..

Jay

sugar is for my morning coffee...

[Magne]

your body is like 80% water, which is why you can glue your fingers together faster than two sticks of balsa.

Off topic I know, but is it true that CA was invented during the Korea War in the 50's to do "field repair" of injured soldiers???

[BruceWilkerson]

Ok how bout this: is it true that prolonged storage can be had by freezer storage of the CA bottles? Anyone know the extent of time added? I have 20 or so 2 oz [ all new sealed ] in there now when I use what I have I grab one out of the freezer let it come up to room temp and use it.
One thing I have noticed the metal CA even NIP will go bad very quick when left out in the open........ even though they were sealed and never opened [ time frame of only 45 days ]although I may have had gotten 2 bottles that were past their prime to start with?
Thx. BW

[erazz]

your body is like 80% water, which is why you can glue your fingers together faster than two sticks of balsa.

Off topic I know, but is it true that CA was invented during the Korea War in the 50's to do "field repair" of injured soldiers???


Nope :)

It was invented by Kodak at first when they tried to make a plastic for gunsights...

http://inventors.about.com/library/inventors/bladhesives.htm