I need to use a few drops of super glue every week or two sometimes I'll get a project where I use 1/2 of one of those mini tube (2 gram tubes). It seems no matter what I do, how quick I put the lid back on, how tight it is, the glue dries out before I use it again. Once in a while, I can squeeze a little out. The best for "keeping" is "The Originial SUPER GLUE" Gel. IT seems to not dry out as fast in the metal squeeze tube.

I'm wondering if anyone has any suggestions on how to make this stuff store better. I've seen 1/2g tubes (super small tubes, almost worthless if you spill a drop). Then there are the plastic containers (maybe 14-20g) where the sides "squeeze" some and it comes out the nozzle. Then there are some that are 4-6g and I've tried these and they get dry real quick too. I just don't know if there is a trick or one brand is better or what.

I'm also wondering if there is anything comparable to JBweld. I've used it on a number of occastions and it is pretty nice stuff but it gets pricey at $8 / 2oz. I'm not trying to be cheap as I think JB weld deserves business as it has a good product. The problem is that I don't have the $$ so I have to find alternatives to make due.


If anyone knows anything about 2 part epoxies that use Bisphenol-A (BPA) and epichlorohydrin (at least that is what the MSDS said on my 2 part 50/50 epoxy (dried clear and is pretty/very hard). Is it really just those two chemicals mixed for an epoxy of some kind (there are many different epoxies). I have also seen some that are 99.9% from one bottle, then a few drops of hardener - MEKP (methyl Ethyl Ketone Peroxide). Can that be added to the BPA/Epichlor mix to make it even harder?

Sorry if this isn't so much "electronics" but I have found a need for glues and epoxies very often when working with this stuff. I thought some of you may be knowledgeable on this.

 

I have used cyanoacrylic adhesives (aka "CA" or "super glues") for years. I store them in canning jars with rubber sealed lids. For longterm, I put them in the freezer, but when you use reduced temperature, be sure they are thoroughly warm before opening. I habitually date thing things I store. I have kept and used an open CA plastic bottle for at least 2 years. The trick is high quality CA and minimizing exposure to moisture. I generally put a piece of capillary Teflon tubing in the stem of the open bottle. That substantially reduces movement of water vapor into the bottle. Moisture-curing polyurethanes are more difficult to store, as they are much more sensitive to water.

As for epoxies, check out the TDS (technical data sheet) for various ones. You will probably find that the strongest epoxies are not 1:1 mixes. MGS, West Systems, others are typically 1:3 to 1:5 ratios. There are many brands. The features you look at depend you your application. Viscosity, pot life, cure time/temperature are usually important to any application. What values for strength you need depends more on application. For what I do, peel strength is often important, as when bonding metals together. There may even be a measure for bonding metals with and without pre-treatment. NB: The aerospace industry has developed many proprietary metal pre-treatments for bonding. You can often find something similar on the Internet, e.g., for bonding aluminum.

For reactive adhesives that are in larger quantity (e.g, pints), and particularly for the catalysts for epoxies, I usually flush the container with argon before closing it. The resin for epoxies is not as sensitive and can usually be stored without such a precaution. Argon is relatively cheap and heavier than air. It can also be used to store an opened bottle of wine, if you are ever faced with that "problem."

John

 

i guess i've found a substitute of this (from these) very practical

• for (water-/weather proof) metal to metal bonding and
• for non-elastic (the content should not be altered by external forces) package forming
• can be drilled cut(at various curing stages!) sanded ...

?? If anyone knows how to make air-bubbleless epoxy mix - it'd be very useful piece of knowledge (must be a sealed mixing in fresh foil or alike - stronger!)

 

How do you expect any recommendation when you don't even tell us what you are gluing?

What requirements do you have?
- substrate material(s)
- types of loads (static, dynamic, torque vs simple shear, ...)
- shear strength
- gap-filling, simple lap joints, butt joints, ...
- Working time,
...

 

Cyanoacrylate (super) glues gave me fits. Then I went pro.
Got it from a hobby and modelers shop about 3 years ago. The nozzle is clear so you can see if it is clogged and squeeze the bottle in an upright position till it clears. The cap snaps on tightly and it is a thick heavy bottle.
Cheap super glue is half the price but this is 100 times better. Just used it on my glasses last week and it still flows. This is not the runny type, although they make that version as well, this stuff takes about 1 to 3 minutes to set up.
I also use JB weld at home and at work. Great product.
Use slightly more hardener than steel if you want it to dry quicker.

 

?? If anyone knows how to make air-bubbleless epoxy mix - it'd be very useful piece of knowledge (must be a sealed mixing in fresh foil or alike - stronger!)

Haven't applied this technique to epoxy, but used it with poly casting resin. Build a vacuum chamber. Using a long setting epoxy, mix it and place it in the chamber. Draw a vacuum and wait for the air to clear. Use immediately before epoxy sets.

 

For bubble-less epoxy, use a static mix head. They have all sizes from caulking tube (even bigger) to syringes. Just replace the tip after each use. About $2 each.

 

On super glues, I have to agree with jpanhalt and kermit, the model/hobby store glues are way better than the hardware store types. I'm still using a couple of bottles that are 3 or 4 years old. Store them in a tight lid (plastic peanut butter jar) in the refrigerator door shelf. But bring them to room temp before using.

 

Haven't applied this technique to epoxy, but used it with poly casting resin. Build a vacuum chamber. Using a long setting epoxy, mix it and place it in the chamber. Draw a vacuum and wait for the air to clear. Use immediately before epoxy sets.

Don't forget to put an air filter between the vacuum pump and the bell jar. If you don't the epoxy vapor will eventually destroy the pump.

 

Don't forget to put an air filter between the vacuum pump and the bell jar. If you don't the epoxy vapor will eventually destroy the pump.

That sounds like an urban myth to me. By "air filter" do you mean and activated carbon filter? Any data?

John

 

Used this technique with polyester casting resin without any filters and without any problems.

 

I've degassed low viscosity potting epoxy in a vacuum chamber with no deleterious effect to the pump but time will tell. By the way, when degassing, you need a container many times the volume of the resin to contain the foam until the bubbles pop.

 

That sounds like an urban myth to me. By "air filter" do you mean and activated carbon filter? Any data?
John

Indirect experience. The "chemicals" guy was doing a lot of potting and molding using epoxies and urethanes. After a while the pump started making funny/bad sounds. Someone (not me) concluded that there should have been a filter to protect the pump from the mist caused by the bursting of the bubbles in the potting material. I have no reason to doubt this theory.

I don't have any idea what kind of filter would work the best. I would guess that any filter would be better than no filter. I would put a paper filter right at the bell jar to protect the hose and pump. Hopefully someone else here can help fill in the big gaps in my knowledge...

 

I need to use a few drops of super glue every week or two sometimes I'll get a project where I use 1/2 of one of those mini tube (2 gram tubes). It seems no matter what I do, how quick I put the lid back on, how tight it is, the glue dries out before I use it again. Once in a while, I can squeeze a little out. The best for "keeping" is "The Originial SUPER GLUE" Gel. IT seems to not dry out as fast in the metal squeeze tube.

I'm wondering if anyone has any suggestions on how to make this stuff store better. I've seen 1/2g tubes (super small tubes, almost worthless if you spill a drop). Then there are the plastic containers (maybe 14-20g) where the sides "squeeze" some and it comes out the nozzle. Then there are some that are 4-6g and I've tried these and they get dry real quick too. I just don't know if there is a trick or one brand is better or what.

I'm also wondering if there is anything comparable to JBweld. I've used it on a number of occastions and it is pretty nice stuff but it gets pricey at $8 / 2oz. I'm not trying to be cheap as I think JB weld deserves business as it has a good product. The problem is that I don't have the $$ so I have to find alternatives to make due.


If anyone knows anything about 2 part epoxies that use Bisphenol-A (BPA) and epichlorohydrin (at least that is what the MSDS said on my 2 part 50/50 epoxy (dried clear and is pretty/very hard). Is it really just those two chemicals mixed for an epoxy of some kind (there are many different epoxies). I have also seen some that are 99.9% from one bottle, then a few drops of hardener - MEKP (methyl Ethyl Ketone Peroxide). Can that be added to the BPA/Epichlor mix to make it even harder?

Sorry if this isn't so much "electronics" but I have found a need for glues and epoxies very often when working with this stuff. I thought some of you may be knowledgeable on this.

Since my first REAL job (other than washing cars) was in an adhesives laboratory, I developed a real liking for the ritual of mixing two-part epoxies....and when done properly they are as strong as any single superglue. (Although THE strongest adhesive is a hybrid of cyanoacrylic and epoxy). Mixing epoxy is about the only real chemistry I do any more.