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Super Glue mini-bottle that doesn't harden by itself while stored capped?

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VK3DRB:

--- Quote from: gnif on April 24, 2023, 02:27:41 am ---
--- Quote from: antenna on April 24, 2023, 02:24:39 am ---
--- Quote from: silenceisblissfulness on April 24, 2023, 12:00:26 am ---What is worse with superglue is when people buy cheapo, generic brands, thinking "that'll do" - my Dad bought one recently, it came out like a semi-sticky kinda gel liquid, took about an hr to set. Junk.

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add a pinch of baking soda.

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This is actually a really good tip for repairing plastic parts in general. Bicarbonate of Soda mixed with superglue creates a very hard, sandable, and strong filler.

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Talcum powder also works. I stuck two thick outdoor ceramic tiles together for a window sill at the front of the house using talc and super glue mixed into a paste, prior to selling the house 41 years ago. It lasted in the weather outdoors until last year when our old house was completely bulldozed by a new owner. Hard as rock and UV/water proof.

A really good glue for general work is polyethylene glue. That stuff is is incredibly strong. Works on plastic etc.

Psi:
Best I've found is a combination of the following.

- A good quality superglue  (I like 'CA hot stuff' )
- Stored in fringe
- After every use and before placing cap back on, squeeze and release the bottle a few times with it held vertical to clear out the glue currently sitting in the end of the nozzle and give it a wipe.  (to do this you need a brand/bottle that allows you to do this and ideally see if any glue is in the nozzle)

jpanhalt:

--- Quote from: Cecil on April 24, 2023, 04:30:57 am ---It's just acetone which I always have on hand;  Second, the glue will last twice as long before hardening in the bottle if stored in a refrigerator.

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Are you sure your acetone is not wet?  As with most catalyzed polymerizations, the amount of catalyst can affect the outcome.  Too much can lead to chain shortening and a weaker polymer.  It is possible the accerant you got had a small amount of "base" (Lewis) in acetone as a solvent to prevent having too much catalyst.  Maybe it was just wet acetone sold at a huge profit?  The accelerants I have used were not acetone based but did have an undefined solvent.  It smelled similar to vanilla.

I just tried experiments with 1 and 2 drops of liquid CA into 3 ml aliquots of reagent acetone.  It just dissolved in both cases.  If the acetone was enough to set it off, whatever polymers it formed must have been pretty short and simply redissolved.  One drop of water to each caused turbidity.  Of course, the water could be precipitating the acetone-initiated polyers.  It could also be initiating polymerization of unreacted CA. 

If one had access to a drying chamber and appropriate vacuum apparatus, you could do the first step, then evaporate the acetone and test whether the residue was still reactive.  This post: https://chemistry.stackexchange.com/questions/102488/can-superglue-cyanoacrylite-be-thinned-with-acetone-and-still-harden  suggests that acetone acts as a solvent not a catalyst.. 

I am inclined to agree with the statement on Stackexchange.

As for the discussion of bicarbonate, it doesn't take much to promote polymerization.  While it is true an excess can be used as a filler, modelers will just rub difficult woods (e.g., spruce) with the powder and then wipe the visible amount off.  That leaves enough to give a strong bond, e.g., cap strips on composite spars. 

Someone:

--- Quote from: jpanhalt on April 24, 2023, 11:33:10 am ---It is possible the accerant you got had a small amount of "base" (Lewis) in acetone as a solvent to prevent having too much catalyst.  Maybe it was just wet acetone sold at a huge profit?  The accelerants I have used were not acetone based but did have an undefined solvent.  It smelled similar to vanilla.
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There are MSDS's showing acetone based activators with the possibility of no other components (SDS No. : 153652) but leaving open a significant 10% mystery ingredients.

The activator instructions suggest acetone is just a solvent:
"allow the solvent time to evaporate under good ventilation until the surfaces are completely dry"
"after activation, parts should be bonded within 7 days. Contamination of the surface before bonding should be prevented"
if the accelerating action was acetone modifying the surface it could last indefinitely, and if the acetone is simply a water carrier/disperser then the effect would not last so long. Both of those could improve or speed up the bond with neat acetone, possibly explaining the positive experiences people are mentioning with neat acetone.

I'd agree with you that the acetone is a solvent carrier for the actual activator in the commercial product.

madires:

--- Quote from: all_repair on April 24, 2023, 03:46:14 am ---
--- Quote from: antenna on April 24, 2023, 02:24:39 am ---add a pinch of baking soda.

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Try ashes, incense ashes,  better than baking soda.  Saw dust works too.  Finer the particle, the better it is.

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The 'pro' filler sold is glass powder.

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