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brendan stemp
28th June 2011, 10:16 AM
I recently heard some concerning news about CA glue failing after time (10 yearsish). I am wondering if anyone has had experience with this or any more info on it.

Is it dependent on the quality of the glue (are there better quality CA glues than others?) or is it a matter of how woodturners often use it; ie mixing it with wood dust and using it as a fliller? Are there other factors at play?

Or is it a myth perpetrated by unscrupulous pva glue companies?

It is of concern to me because I do use it as a filler but will stop this practise if I know it wont stand the test of time. I have heard that some collectors, before they buy a piece, ask the question "have you used CA glue?" If so they wont buy it.

An important issue to get to the bottom of, me think.

Ozkaban
28th June 2011, 10:41 AM
Interesting thought Brendan.

I'm not 100% sure but it would seem possible - CA does become very brittle and I've found it to be susceptible to shock type movements (eg dropping something). Don't know about it failing because of age though.

Cheers,
Dave

WOODbTURNER
28th June 2011, 11:17 AM
Brendan,

I read way back about ca failures in a USA article but like you said is it rumour

Jim Carroll
28th June 2011, 01:43 PM
I have also heard the rumors but the proof was not whether it was the application or the applicator that was at fault.

As with all finishes these two reasons are the main fault.

rsser
28th June 2011, 04:53 PM
Have only had one bad batch of bargain shop CA and it failed immediately!

hughie
28th June 2011, 05:25 PM
Have heard the same, but have yet to see it myself.

wheelinround
28th June 2011, 05:34 PM
Have heard the same and had CA fail on me but not involved with woodwork.

Over the years I have seen and had Epoxy fail various situations. Similar story 10 year life span. :rolleyes:

Mulgabill
28th June 2011, 06:14 PM
Like others have said, I have heard rumors, perhaps urban myth, :shrug: but i will watch this thread with interest.

Scott
28th June 2011, 07:17 PM
Essentially CA is a synthetic polymer, a plastic from the acrylic family (think clear plastic sheets). Considering this I would imagine CA would last a little longer than 10 years. The only situation where acrylic (and CA glue) would degrade is if it would be exposed to prolonged UV radiation (the sun, which is why polycarbonate is better for roofing).

I reckon it's a myth Brendan.

Skew ChiDAMN!!
28th June 2011, 07:42 PM
Myth? Sorta.

The thing with ethyl CA - the type most oft used in WW - is it doesn't stand up to moisture/humidity very well. Given certain conditions and enough time, it'll go cloudy and eventually fail.

High (90°Cish) temperatures can also cause it to break down.

However, isn't this true of most other glues - and often the timbers they're used on - as well? Perhaps not those specific factors, but they all have their own particular kryptonites. :;


Somewhere around here I have a lot of tech info & research on the stuff, but I'm too lazy to hunt it up. :B

dai sensei
28th June 2011, 10:00 PM
I have had no problems with coatings or fillers, but yes I have had failures with glued joints in time. It is a brittle glue, thus if the wood moves, it can give way if there is insufficient bond area. All of the failures I have had were with my early segmental bowls where I had thin walls, failing at a number of joints, after 3-5 years.

Cliff Rogers
28th June 2011, 10:57 PM
Biggest problem I have with CA is that I fail to use it all before it goes off in the bottle. :(

WOODbTURNER
28th June 2011, 11:21 PM
Cliff,

Do you store it in a fridge? Up here in hot and humid Darwin it lasts a very long time when stored in one.

orraloon
28th June 2011, 11:23 PM
I have to agree with Cliff. So many tubes have gone off before they were used up.
I am now approaching the age where if it lasts 10 years it will most likely be ok.

Paul39
29th June 2011, 06:21 AM
Biggest problem I have with CA is that I fail to use it all before it goes off in the bottle. :(

I buy bunches of tiny one use tubes when on sale.

I would think even if one used PVA or any of the whiz bang, stronger than wood, glues, if the piece moved around much it would break beside the glue line. Cracked is cracked.

Cliff Rogers
29th June 2011, 09:15 AM
In a fridge in zip lock bags slows it down but doesn't stop it.

brendan stemp
29th June 2011, 10:00 AM
Thanks to all who replied. Very informative and somewhat reassuring.

The thread seems to have been detoured elsewhere (storage of CA glue wasn't the question) so I'll sign off on this thread now.

Jim Carroll
29th June 2011, 10:05 AM
Thanks to all who replied. Very informative and somewhat reassuring.

The thread seems to have been detoured elsewhere (storage of CA glue wasn't the question) so I'll sign off on this thread now.

But Brendan storage at the outset can be part of the problem.

If not stored properly and then applied properly could lead to problems down the track.

Grant Mack
1st July 2011, 04:10 PM
I have been told that moisture e.g. condensation in the bottle after removal from a fridge and exposure to light are the two major causes of CA not lasting long regarding shelf life.
So I find storing in a cool, dry, dark place has not given me any problems with the glue still working.
Have only been turning for four years so will have to see about failures in six years time!
Only use it for filling cracks using sawdust and not gluing with it.
Regards
Grant

Grant Mack
1st July 2011, 10:50 PM
I have been told that moisture e.g. condensation in the bottle after removal from a fridge and exposure to light are the two major causes of CA not lasting long regarding shelf life.
So I find storing in a cool, dry, dark place has not given me any problems with the glue still working.
Have only been turning for four years so will have to see about failures in six years time!
Only use it for filling cracks using sawdust and not gluing with it.
Regards
Grant
Should read "I only use it for filling cracks, using sawdust and not gluing joints with it."

nalmo
6th July 2011, 02:05 AM
I find that the tip of the bottle gunks up with dried CA, then the cap splits and doesn't seal the bottle properly any more.

Tim the Timber Turner
6th July 2011, 01:56 PM
I find that the tip of the bottle gunks up with dried CA, then the cap splits and doesn't seal the bottle properly any more.

I never :no: replace the cap, just throw it away.

Make a rack to store the bottles upright or you loose the contents.

Leaving the top off allows the tip to drain and it won't block up, well not as quickly.

Vic Wood taught me this tip 20 years ago.

Onya Vic:2tsup:

Cheers

Tim:)