Superglue and epoxy resin not working. What next?

[Charlie]

I managed to drop one of my wife's trophies and broke one of the
figure's legs.
I tried superglueing and that didn't work, so I tried one of those two
part epoxy resins (with a double plunger type thing).

I am able to clamp it up really neatly but after 12 hours the joint
just comes apart with the glue still wet. What am I doing that is so
fundamentally wrong. I thought this was an easy job. I need to fix it
in a hurry as she doesn't know yet that I've broken it. I'd like to
get it fixed really neatly before I 'fess up.

Cheers

[The Natural Philosopher]

China?

Firs remove all the epoxy with a solvent - acetone is good.

Now mix up more. This time mix it THOROUGHLY. 99% of all epoxy failures
to cure are down to inadequate mixing, the other 1% are not waiting long
enough.

Stick it back together and remove all excess with acetone/cellulose
thinners/nail varnish remover,.

Splint it so it wont come apart,

STOVE it in a WARM oven at < 100C. This speeds up the set time and
improves strength, heat resistance and water uptake of the final bond.

Put it back and pretend you didn't notice.

[Maria]

Sounds like you mixed the epoxy with insufficient hardener. I've even
used it to mend a leaking car radiator, and never found it to fail.
The double plunger thing is bloody awful - I've never found that to work
that well because it seems to dispense the incorrect amount due to
uneven pressure on the plunger. Can you try a traditional type that
comes in two seperate tubes?

[The Natural Philosopher]

epoxy is designed to work at an exact 50/50 mix. (domestic formulations)
it is NOT a 'hardener' Is a two pack mix where the reaction is NOT
catalysed by one, it is *performed* by BOTH.

[Maria]

Oh ok. I must be getting confused by the epoxy things I have used which
do have a hardener.
In any case, I have found it difficult to get the same amount to come
out of the double tube thing, maybe because my fingers are arthritic.
Never had the problem using separate tubes.

[The Natural Philosopher]

polyesters have a 'hardener - a catalyst which sets them off.

The tube may be called 'hardener' in an epoxy, but that's just a silly
away of talking , not the actual reality of how they work.

Its bit like saying that in concrete, you have sand, rocks, cement and
water, which a 'hardener'

[Andy Burns]

Maria wrote:

> On 05/12/2011 12:02, The Natural Philosopher wrote:
>
>> epoxy is designed to work at an exact 50/50 mix. (domestic formulations)
>> it is NOT a 'hardener' Is a two pack mix where the reaction is NOT
>> catalysed by one, it is *performed* by BOTH.
>

> I must be getting confused by the epoxy things I have used which
> do have a hardener.

Who can blame people when even Araldite tubes are marked as 'resin' and
'hardener'?

[Nick Odell]

Don't be too hard on people for thinking that: even the brand leader
comes in tubes marked 'resin' and 'hardener.'

http://www.conservationresources.com/Main/section_34/section34_05_files/image003.jpg

Nick

[The Natural Philosopher]

well its misleading packaging. They should have said 'part A' and 'part B'

Wiki makes the point using plenty of inverted commas

http://en.wikipedia.org/wiki/Epoxy

But anyway, the key thing is as near equal quantities and very very good
mixing..as you can get, and heat is definitely a plus to accelerate
setting, promote better mixing and form a stronger joint.

[Gazz]

>>>>> I managed to drop one of my wife's trophies and broke one of the
>>>>> figure's legs.
>>>>> I tried superglueing and that didn't work, so I tried one of those two
>>>>> part epoxy resins (with a double plunger type thing).
>>>>>
>>>>> I am able to clamp it up really neatly but after 12 hours the joint
>>>>> just comes apart with the glue still wet.

Super glue (cyanoacrylate) needs water to make it set, usually the moisture
in the air is enough, but you can make it go off sooner by spraying the
joint with a little water,

you can buy cyanoacrylate kicker sprays, which is basically water and a few
other chemicles, makes the glue go off isntiantly, with lots of heat and a
little smoke, but also causes the glue to bubble up out of the joint in a
white ooze,

But maybe try wetting the break before applying the superglue, but be quick,
as it will then set in seconds... or it should anyway.

[Martin Brown]

On 05/12/2011 11:49, Charlie wrote:

> I managed to drop one of my wife's trophies and broke one of the
> figure's legs.
> I tried superglueing and that didn't work, so I tried one of those two
> part epoxy resins (with a double plunger type thing).

Those double plunger things are a disaster. The resin and hardener have
completely different viscosities and you almost never get the right
amounts out. It is a neat marketing trick that is worse than useless.

The other possibility is that you failed to mix it properly. At any
reasonable ratio you should get a weaker inferior set that takes longer
and has much less strength - maybe even tacky or rubbery but certainly
not still wet after 12 hours unless it is kept very cold.

>
> I am able to clamp it up really neatly but after 12 hours the joint
> just comes apart with the glue still wet. What am I doing that is so
> fundamentally wrong. I thought this was an easy job. I need to fix it
> in a hurry as she doesn't know yet that I've broken it. I'd like to
> get it fixed really neatly before I 'fess up.
>
> Cheers

The other thing you might want to do if it is china is find some of the
epoxy with a white pigment in so that the mend is nearly invisible.
Otherwise you will have a hairline black crack no matter how hard you
squeeze it together. Two tubes is better just don't mix up the lids.

Regards,
Martin Brown

[Owain]

On Dec 5, 11:49 am, Charlie wrote:
> I managed to drop one of my wife's trophies and broke one of the

> figure's legs. ... I need to fix it

> in a hurry as she doesn't know yet that I've broken it. I'd like to
> get it fixed really neatly before I 'fess up.

Pack the whole lot away safely while you repaint the shelf they were
on. Or repaint the whole room if necessary.

That will give you breathing space.

What is it / what's it made of? Can you buy another one?

Owain

[Charlie]

Thanks for all the advice, I had another go with the Epoxy resin and
made sure it was fully and equally mixed. I noticed the first time
round that the two parts didn't come out particularly evenly. This
time I notice a large blob come out that was presumably causing a
blockage in one of the syringes. This time it looks like it's worked a
treat.

Charlie

[The Natural Philosopher]

Charlie wrote:
This time it looks like it's worked a
> treat.
>
> Charlie

YAY!!

[Brian Gaff]

And knowing that helps how? grin.
I agree the plunger stuff is bloody useless. You may wast a lot doing it
the old fashioned way but its going to be a better job.
Brian

--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email: bri...@blueyonder.co.uk
______________________________________________________________________________________________________________


"The Natural Philosopher" <t...@invalid.invalid> wrote in message
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[Gazz]

"The Natural Philosopher" <t...@invalid.invalid> wrote in message

news:jbjkbc$81o$2...@news.albasani.net...

> Charlie wrote:
> This time it looks like it's worked a
>> treat.

Now place it back on the shelf really close to the edge, so that when she
goes round with the duster she knocks it off, and blames her self not you.

[Maria]

And I thought women were conniving!

[PeterC]

This is self-presevation!
--
Peter.
The gods will stay away
whilst religions hold sway

[Maria]

On 06/12/2011 16:54, PeterC wrote:
> On Tue, 06 Dec 2011 15:47:18 +0000, Maria wrote:
>
>> On 06/12/2011 12:30, Gazz wrote:
>>>
>>>
>>> "The Natural Philosopher"<t...@invalid.invalid> wrote in message
>>> news:jbjkbc$81o$2...@news.albasani.net...
>>>> Charlie wrote:
>>>> This time it looks like it's worked a
>>>>> treat.
>>>
>>> Now place it back on the shelf really close to the edge, so that when
>>> she goes round with the duster she knocks it off, and blames her self
>>> not you.
>>
>> And I thought women were conniving!
>
> This is self-presevation!

lol

[Charlie]

On Dec 6, 12:30 pm, "Gazz" <n...@spam.ta> wrote:
> "The Natural Philosopher" <t...@invalid.invalid> wrote in messagenews:jbjkbc$81o$2...@news.albasani.net...

>
> > Charlie wrote:
> >  This time it looks like it's worked a
> >> treat.
>
> Now place it back on the shelf really close to the edge, so that when she
> goes round with the duster she knocks it off, and blames her self not you.

Genius

[Owain]

On Dec 6, 12:30 pm, "Gazz" wrote:
> Now place it back on the shelf really close to the edge, so that when she
> goes round with the duster she knocks it off, and blames her self not you.

She'll blame you for making the shelf too narrow.

Or of the wrong sort of dust-collecting wood.

Owain