MIMF

Why does the nozzle on CA bottles always clog and how can I keep them from clogging?


The CA in the tip of the nozzle is reacting with moisture in the small orifice and hardening. Typically once the CA hardens the user will take a pin and stick it down into the nozzle to open it up only to find it clogs up even quicker the next time. What happens is the pin scratches the inside of the nozzle, which allows even more CA to stay in the nozzle causing it to clog up quicker. This process will be repeated several times until the nozzle is no longer able to be used and gets thrown away.


Some companies have claimed to have a clog-free nozzle, which in reality is only a very long nozzle that you keep snipping the clogged end off until there is no nozzle left and still end up throwing it away. Other companies simply sell you extra caps and nozzles so you can replace them after they clog.



There are bottles that actually have an engineered nozzle that not only will not clog but has three different points of seal to assure the product inside is kept fresh and away from moisture. This cap has a blunt nose, stainless steel pin molded into the cap, which engages into the orifice of the nozzle (not scratching the insides of the bottle) to keep the orifice clean. Inside the tip is a calculated venturie shape, which pulls the CA out of the tip and back into the bottle once the bottle is stood upright. On the very tip of the nozzle is a tapered seat which engages with a tapered boss in the cap creating compression on the tip of the nozzle keeping the nozzle clean and the product inside fresh.



If the tip is wiped and the cap is replaced each time the user is finished with the product the nozzle will never clog. Also, always, always, be sure to allow the glue to go back down the nozzle before recapping. Tapping the bottle a couple of times will help with this.

Just leave the dumb cap off the tip and don't get the tip anywhere near where it can get contaminated with accelerator or finger oils etc. Of course if you only use it once every few months it's going to be clogged every time. Just buy the tiny 3 gram tubes and toss them out when you are done.
Use an unwound el bass string cutoff to clear the clog from the inside. Keep a pair of mini channel-lock pliers handy to unscrew the lid first.
Or just buy lots of Rick's over-priced glue with the super duper tops that never clog and Bob's your uncle.
Tapping the bottle will also ensure that a tiny drop will fly out and get in your eye so be careful always with CA.
A good procedure is to fill tiny pipettes with CA once a week and then toss those when they clog. You'll get much better control and are much less likely to cross contaminate your bottle. You can keep the bottle in the fridge and just warm it up prior to opening it to decant what you need for the week.

The place I get superglue from here in Germany will also sell you a bag of nozzles for the bottles. Quite handy. For the Gel version they have a very fancy system with a kind of built in cleaner - got my first bottle recently - remains to be seen how effective it is.

Don't use the bottle tips at all. Just buy inexpensive pipettes with narrow tips, and fill from the bottle directly. The glue in the pipettes stays liquid for days without issue. Somehow, the glue does not seem to clog the tiny tips. Don't know why. If it does, cut off 1/8" or so and keep using. Store with the bulb down and the tip up. Bore a 1" deep 1/2" hole in a scrap block and drop the bulb end of the pipette in for storage. Works great. I usually find that one pipette will last me for weeks at a time, and I never have to worry about the bottle tip, which is too big, mostly, anyway. The pipette allows for really good control of the amount of CA you are using.

Waddy,
Why don't you post a link to where you are getting pipettes. Not every town is large enough to have a medical lab supply house in driving distance.

Lots of folks order them from web lab supply houses. I have gotten mine from LMII.

I use a 3ml syringe with 27 or 30 gauge needles, and rinse out with acetone after use. Probably overkill, but it puts the glue where I want it.

One cool thing about the pipettes is that if you tug on the tip it will stretch out and lose about 1/2 it's diameter.

You can find pipettes at most hobby stores, amazon.com, and, while I haven't seen them in the store, you can order them from Walmart.com as well.

A number of years ago, I went to a woodworking show, and at the booth for one brand of CA glue (can't remember which one) the guy always wiped the nozzle down after each demonstration, and then he stuck a regular common pin in the nozzle. I think he said it was jut a regular common pin, not waxed or anything. I always have a problem with the nozzles getting clogged, and I don't know why I don't do this, but I seem to be afraid it will get stuck in there (which I suppose is no worse than the nozzle getting clogged).

Star Bond used to do the woodworking shows. They have the thinnest thin CA out there, great stuff but it has a shorter shelf life.

So I asked this exact same question years ago on this forum, and got a bunch of different answers.
I didn't follow any of the advise
I have, however, developed a "discipline" (if you will) that keeps CA bottle tips clean, and the product usable for months - open - in my shop.
It is super easy and simple, and if you do this without fail then you can have clean bottles like you see below.

• 1) When you are going to use CA - BEFORE YOU NEED IT - grab the bottle and un-cap it
  2) Clean any dried glue off the tip AND THE CAP so you are starting with a pristine bottle
  3) Use it and put it aside - DON"T CAP IT
  4) When you are done using it for the day - Clean the tip with a PAPER TOWEL of any-and-ALL glue that is on the outside of the tip

That's it.
This works because:

• 1) You cap and un-cap the bottle a minimum of times, and only when it is clean
  2) You don't pile dried glue onto dried glue - accumulating a mess
  3) Paper towels wick-and-kick CA almost immediately so it does not get spread around
  4) The manufacturers of these glue bottles use a material that CA does not stick to so if there is a MINIMUM of cured glue, it is super easy to remove

As seen below, the bottle of thin (blue label) has been open and in my shop for MONTHS. So long that I have 3 bottles in the fridge because I've over-bought thinking that the open bottle "must be done", but it keeps going-and-going like the energizer bunny.

A dry climate and clean habits helps a lot.

Insta-cure is made by Bob Smith Industries. It is one of the fastest curing CAs out there. Every hobby shop in America sells it with their own little label across the top. It's pretty much all I use most of the time. The 2oz bottles sell for about $8 which makes it a bargain. I go through a bottle every week or two but keep 3-4 open bottles in various stations around the shop.
I repeat I never put the cap on at all. It will start to thicken up after 3-4 months when you get down to the last few drams but there is very little air exchange via the open tip and most of us keep our shops around 40% RH anyway.

After replacing the lid, give the bottle of glue a little tap on your workbench to knock down any liquid that is hanging up at the tip.

David King wrote:Star Bond used to do the woodworking shows. They have the thinnest thin CA out there, great stuff but it has a shorter shelf life.

I've found that it lasts longer than most of the standard 2 oz bottles I try to keep it in I've learned to put the CA bottle back in it's glass jar without fail.

I think you already have better answers than mine, but I will tell you what I do. I first tap the bottle, bottom down, on the bench, to try to drain a few drops from the neck. Then I squirt the remaining residue out of the neck, holding the bottle vertically. Then I wipe the nozzle with a paper towel and acetone. Then I cap it. Next time, the nozzle is still a bit clogged and I keep a sewing needle in my shop for this purpose. I push the sewing needle into the nozzle and neck of my CA bottle until I can squeeze it and air comes out. When I invert the bottle (nozzle down) it always runs easily. That is probably NOT the best way to do it. That's just the way I do it. And it works every time. If you have the resolve and patience to hunt up pipettes, etc., I think those are FAR better solutions to the problem. If you want to keep a sewing needle or pin handy, push the base end of the needle into a common wine cork and use that for a handle.
Patrick

I sometimes end up with a gelatinous mass inside the tip that is very stubborn to get rid of. Pushing it out from the inside seems like the only way to dislodge it.

Yea, CA boogers are a bitch, aren't they?

Waddy Thomson wrote:Don't use the bottle tips at all. Just buy inexpensive pipettes with narrow tips, and fill from the bottle directly. The glue in the pipettes stays liquid for days without issue. Somehow, the glue does not seem to clog the tiny tips. Don't know why. If it does, cut off 1/8" or so and keep using. Store with the bulb down and the tip up. Bore a 1" deep 1/2" hole in a scrap block and drop the bulb end of the pipette in for storage. Works great. I usually find that one pipette will last me for weeks at a time, and I never have to worry about the bottle tip, which is too big, mostly, anyway. The pipette allows for really good control of the amount of CA you are using.

This is how I also handle CA. Took me a while to figure this out. Lots of nasty words flying till I got something that worked.
Tom