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View Full Version : CA Glue accelelerator info



Timbuck
08-05-2018, 10:16 AM
Here is a bit of info you could find usefull.. It's not my words by the way :D

Accelerators
Besides water, cyanoacrylate polymerises also in presence of alcohol and basic compounds (including weak amines). The latter can be used to produce a superglue “kicker” – a compound which triggers quick polymerisation of the glue.

Baking soda is one well-known substance with this effect. If you apply a layer of superglue to a seam and gently pour baking soda over it, the glue will cure very quickly. It makes for most effective filler for smaller jobs, and the baking soda results in a slightly rough surface which is good for sanding.

The great advantage of using superglue as filler is the total absence of shrinking which plagues most solvent-based fillers on the market.

There are also commercially available liquid accelerators, but as baking soda has the same effect, I personally prefer it over another harmful chemical in my workshop.

Like water, the accelerator also affects the reaction through surface contact, so it will be much less effective on thick layers of glue. When filling larger recesses with superglue, it is therefore advisable to build up the volume in several thin layers rather than applying a large volume of glue at once.

With these precautions (i.e. working with small amounts at a time), CA can also be used for moulding smaller detail parts, which I have tried with success.

sequoia
08-06-2018, 06:07 PM
Interesting. I did not know that baking soda (sodium bicarbonate) acted as an accelerator for CA glue. I personally love CA and use the accelerator all the time. However, now I know I don't need the expensive nasty smelling stuff... Gonna do a few experiments first though. Does it leave that ugly white precipitate which can be bad. Plus, could you mix the baking soda in water to make a liquid or would a solvent be better. Hmmmmm... I probably will stick with the stuff out of the bottle.

Oh, and I'm sure everyone knows, that little puff of white gas after accelerator is added is pure cyanide gas. Do not sniff your uke :stop:

Ken Franklin
08-06-2018, 09:55 PM
Can't remember where learned it but you can mist a fine amount of accelerator on CA to prevent the white blooming. Put an accelerator soaked cotton ball in a squeeze bottle with a small tip. Then just squeeze it over the glue to form a fine mist.

A cabinet maker friend of mine likes to just breath on the the CA to kick it. Like when you're cleaning your glasses.

Beau Hannam Ukuleles
08-07-2018, 06:58 AM
Dan Erlewine (from the Stew Mac videos) puts accelerator in a bottle and blows just the air out of the bottle to kick the ca off.

ChuckBarnett
08-08-2018, 07:30 AM
Okay, I'm missing something (being a newb...) Super glue seems very quick so what is the purpose of an accelerator? I've never used it and have only heard/read that term recently.

sequoia
08-08-2018, 07:17 PM
CA glue is quick for sure, but not that quick alone. It can take minutes to grab and up to 24 hours to really bind. Accelerator makes the bond instant. This is handy when glueing parts that must hold instantly. A must for CA gluing. Just watch out you don't glue yourself to the instrument. It happens. The great part about accelerator is use on parts that are under tension. Think binding. The stuff is a dream for luthiers. Also a nightmare for restorers down the line.

ChuckBarnett
08-10-2018, 06:24 AM
Thanks, that helps! I've simply not had enough experience to know that.
Didn't realize CA glue is a good choice for binding. The only binding I've done is the fretboard I just finished- straight lines...

sequoia
08-11-2018, 06:08 AM
Here is a Youtube video from Robbie O'Brian demonstrating a CA binding method. I use this method with good results.


https://www.youtube.com/watch?v=8j5rkKOOyiA

ChuckBarnett
08-11-2018, 05:45 PM
Thank you. That sure makes a lot of sense to me. I may try that.

On the subject of binding, is there a standard dimension that one should shoot for in terms of width and depth? I'm going to keep it simple this first go around and make binding from the koa that I have. That will tie in with the binding on the fretboard as well as the headstock veneer. I'm not so naive as to think that this will be an artistic marvel, this first ukulele. In fact it will certainly be unique. But in thinking about instruments, they're dimension's, etc, a guitar is considerably bigger than a ukulele and I would think that the binding should be appropriately sized. Maybe? Maybe not?

sequoia
08-11-2018, 06:22 PM
Yes, the binding you buy is dimensioned for guitars and is thus a little too big for ukuleles. I don't have the dimensions off hand for what I use and I'm too lazy to get up to measure but would guess about 2/3 the width and depth. Or whatever. I like a smaller binding look... Some pictures of what I think looks good.

I really would encourage you to use the CA method. However, there are a couple of potential pitfalls that should be avoided as I have learned through hard knocks.

1: fill your rebate channels with a dilute solution of shellac before using the glue to prevent the glue from running up the grain lines. A very ugly look. I absolutely ruined a beautiful old sinker redwood top when I didn't seal the grain before gluing. (picture NOT included).

2: Skip the SMD binding tape and use a less aggressive tape to tape your bindings. Seal your top and sides with the dilute shellac to prevent grain lifting and staining. Try not to let the CA to seep under your tape. It can create a reaction with the glue on the tape and leave a nasty residue not unlike bubble gum. Not a disaster, but means a lot of extra sanding and the goo glogs and ruins you sandpaper.

Other than that, the method is nearly foolproof. Good luck! PS: Koa is a good choice. Bends like a dream and very polite.

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