Glue between superglue and gorilla

[akis]

I have the standard gorilla glue which cures with water and expands to 4 times its volume. Although it is extremely strong, because it expands it is quite tricky to use right. I also have an industrial superglue, which does not expand at all, but it cannot fill - it needs to be very thin.

Is there a glue as easy to use as the superglue but that would also fill a little?

[Macbeth]

I've not tried it, but apparently baking soda mixed with superglue is pretty good.

[timb]

Epoxy? It doesn't expand, per say, but it does fill.

Epoxy Pro Tip: After mixing and applying the epoxy, use a heat gun set at 100c, it will cause the epoxy to become much more viscous, allowing it to run into cracks. Remove the heat and it will set within seconds!

[Psi]

also, the difference between $2 shop epoxy and marine grade epoxy is like night and day

[rollatorwieltje]

Zap a Gap. It's just cyanoacrylate, but slightly thicker than the very runny stuff it normally is. It doesn't expand though, it's more suitable for gluing parts that aren't entirely smooth. It's quite popular in the scale modeling scene for gluing stuff like foam and wood.

[akis]

Can you have epoxy in one part ready to use?  The Araldite that I have the screw caps get stuck on the metal tubes, the tubes get twisted and squashed, and basically I have used the glue twice and then the tube breaks...

[Tomorokoshi]

I like this:
http://www.digikey.com/product-detail/en/DP-190-GRAY/3M155868-ND/3864541

Otherwise for mechanical use JB Weld also works okay.

The 5-minute stuff is too brittle for anything.

[TheSteve]

A good hobby store will have thin, medium and thick CA - the medium or thick is generally used for gap filling

[timb]

Can you have epoxy in one part ready to use?  The Araldite that I have the screw caps get stuck on the metal tubes, the tubes get twisted and squashed, and basically I have used the glue twice and then the tube breaks...

Sure you can have epoxy in a single tube, but it'll be solid!

Seriously though, I've seen some two part epoxy in the split tube that auto-mixes in the nozzle as you dispense it. Though, seems like a great way to get a clogged nozzle to me. I'll stick to the one tube with twin nozzles type myself.

[akis]

I just bought the JB Weld which is like the previous Araldite set I used to have. Maybe I mixed the caps and that's why they seized. They should be made different diameters like diesel and petrol pump nozzles.

Superglue has a small nozzle / applicator so I can just use exactly where I want to as much as I want to. With epoxy you have to mix it first on a sacrificial surface, and then apply it with a spatula - not the same as using a bottle with a thin nozzle. Maybe I could use a disposable syringe if the mix stays liquid for a whie?

[Armxnian]

Isn't jb weld color coded? I have the regular one, red and black tube and cap.

A syringe might work, but the viscocity isn't super low so it might be hard to get it out.

I agree preparing epoxy is a bit annoying. You need a disposable surface, a disposable mixer, and a disposable applicator. It's also useless unless you get a very good application. But it does work after the cure time. I broke the tang on my collectors lord of the rings sword by chopping up some branches in the backyard. No access to an oxyacetylene torch so I used jb weld to repair it. I've tried to intentionally break it after the repair as a test, but can't. Still going strong today.

[akis]

Maybe my mind is playing tricks onme, but I seem to remember the caps were black and white and the tubes had mixed colours, and it was not obvious which goes where.

What did you mean by "It's also useless unless you get a very good application" ?

[Armxnian]

Hmm... I also remember something about a black and silver cap... odd... But in any case, I doubt they were the same, and if they are, you could always look to see which cap has the hardener and which has the metal material, or just clean them out.

If you read the instructions, it tells you that you need a flat surface and you need to clean the surface before applying. They mention it for a reason. If you do not get good contact between joints, it will not bond. For some versions, you need to apply pressure in the first few minutes. So set a book on the object or hold it for 20 minutes... if you don't, it will create a really bad bond, or not bond at all. If the stars all align, your repair will be successful. For some jobs it will work with ease, for others it just won't work at all and you need to use something else, just my experience using off the shelf epoxy.

[akis]

I had thought the whole purpose of using the epoxy was its space filling properties (therefore good contact NOT required), unlike superglue which seems the more you apply the more chances of never setting it has.

[Armxnian]

Well it depends on what you're trying to bond. Epoxy is a liquid before it hardens, so you can't just "fill"something unless it's a hole. It needs to make good contact with the surface of the object, and other parts of the epoxy. What exactly are you trying to do?

[SeanB]

Epoxy works both mechanically and chemically. If the surface prep is not done right then you lose the chemical bond it makes with the surface, leaving only the mechanical hold. Smooth surface and there is not much mechanical hold so it fails. The cleaning and prep to remove all oils and loose particles from the surfaces, along with creating a large number of fresh reactive surfaces to chemically bond to, along with making minute furrows for the mechanical bond, is very important.

For superglue accelerator works wonders, though here in summer I do not need  to bother, as the humidity in the air does a pretty good job in most cases. The thickened superglues, or the baking soda as filler ( lots of thin films bonding at once to fill the gap) do work well, though they can take a fair amount of time to cure. Old superglue that has had the lighter components evaporate out leaving a thick goo also has pretty good gap filling properties.

[Ian.M]

Never mixing up your Araldite caps isn't rocket science even if you are colour-blind (the caps almost invariably match the background colour on the tube).  Simply dispense one component, and replace the cap before dispensing the other component.   If the tube nozzle has excess resin/hardener round it or protruding, wipe with a clean paper towel before recapping it or you will have a nasty sticky mess that may make the cap difficult to remove if you leave it for months.

None of the tools for epoxy work *NEED* to be disposable.  You need a polypropylene mixing tray or cup as epoxy doesn't bond to it so any residue can just be popped off.   Uncured epoxy can readily be removed with a mixture of equal parts spirit vinegar, methylated spirits and a dash of dish detergent. followed by a water wash.  The acetic acid 'kills' the polymerisation reaction, the alcohol helps dissolve the epoxy, and the detergent helps keep the epoxy from redepositing when you wash it.  You *MUST* wash thoroughly and make sure the tools are totally dry without any vinegar smell before reuse.   I've got one stippling brush that I've been using for epoxy work over a 10 year period and its bristles are still seperate and flexible.

When dealing with difficult to bond metals like aluminium, copper, tin, lead or zinc that tend to form a weak oxide layer on the surface, its advisable to sand and clean as normal then sand the wet epoxy or other adhesive into the surface.  Wipe off the excess and the sanding debris leaving a smear of adhesive on the surface and immediately add fresh adhesive and make the joint.

This procedure excludes the air from the bond surface, giving you a direct adhesive to metal bond rather than an adhesive to oxide to metal bond.  Aluminium and magnesium alloys are the worst for rapid oxidisation, and should always be bonded this way.

[German_EE]

When it comes to glue what I'd like to hear from is someone from Boeing or Airbus. Both of them use large amounts of glue in aircraft manufacture because it's lighter than rivets and they get it right almost every time. So, what's their secret to fixing together two lumps of aluminum using just a thin film of glue?

[SeanB]

That is a 2 component epoxy, using a disposable mixing tube on the dispenser to thoroughly blend the 2 parts during the time it leaves the 2 tubes and arrives at the end. This then is applied to a clean oil free surface that has previously had a surface preparation film on it ( the green epoxy paint you see on the inner airframe, older used a yellow Cadmium coat but they moved to a less toxic coat a while ago) and a final prep just prior to the bonding action. This is then held with the rivets till it is cured, the rivets providing the clamping force required on the film of adhesive. IIRC the epoxy has around a 15 minute pot life and cures somewhat during the first 4 hours, but needs 48 hours till it is finally cured, though depending on the actual one in use this can vary considerably, and also can be accelerated with a heat cure.

You throw the mixing tube away with each change of tubes, they come as a prepack with the 2 aluminium wall tubes ( depending on the mix ratio different diameters), a screw in holder that holds the tubes in the dispenser then the mixing tube and it's internal labyrinth mixing path to the dispensing nozzle, all in a pack often having a small bottle of solvent, nitrile gloves, lint free swabs and a scotchbrite pad to clean the surface, used for panel rework when you have to remove the panel. The dispenser is also used to apply the windscreen mastic, which is really hard to remove from the metal.

Similar to what is done to install a modern windscreen, which is bonded to the car body structure, as it is a part of the passenger compartment rigid frame, and has to absorb impact energy. Audi use it as well to bond body panels, though there they use a jig that holds them in alignment till the heat cure is finished.

[KL27x]

I agree preparing epoxy is a bit annoying. You need a disposable surface, a disposable mixer, and a disposable applicator.

I mix small amounts of epoxy on a small end grain cutting board (sealed with linseed oil) using a small scraper knife/chisel. Also works well on a bit of glass, if you have any handy. Over the years, I have gotten to where I often use every little bit of the epoxy with no waste. After scraping/gathering/using all the epoxy, nothing left to see. Just a wipe down of the board and knife with a paper towel and alcohol. Been using the same tube of red/black JB weld for a decade.

It makes quick work of the mixing, too. Smear it down over the board in a microthin layer in one direction. Scrape it up at a 90 degree angle. Repeat a few times.

[joeqsmith]

Depends what you are trying to bond.  When working with circuit boards where I need a thin glue, I use Black Max and Tak Pak, both with the accelerator. 

[RobertBG]

You can add micro balloons to a CA glue like superglue that will really help filling gaps.They also have a few that are rubberized and flexible used in the speaker industry that are amazingly strong yet flexible.Superglue or CA glues have come quite a long ways and with a accelerant they are truly time savers.

If brute strength is required epoxies are tough to beat and I've seen panel bonding adhesives where the steel or aluminum rips before the metal does.Dont be surprised to see a body shop glue a quarter panel on a car these days instead of welding The downside is they are long acting and tend to get pricy and dont  like moisture during the curing process.

polyurethane based Like gorilla glue and PL construction adhesives can foam up as you've seen but generally are pretty good all purpose glues and are moisture and UV resistant.With These they tend to foam more when moisture is present while curing but it wouldnt hurt to try another brand as they dont all foam like Gorilla do.

It all really depends on what your'e trying to accomplish but I tend to use CA with or without 3m micro balloons a lot along with a good old hot glue gun on my electronics stuff the most.


 

[LaserSteve]

If you have time for it to dry, one of the secret aerospace epoxies is the MgO filled Hysol 1C Off White. Ultra low outgassing, and withstanding high temps are its main characteristics. Shelf life is only a year or so, though.
Not the strongest in shear, but damn good if used properly.

Hour or so to really set, and 24 hours to rock hard.

With one additive changed, it goes by the name Torrseal for ultra high vacuum work.  I just use the 1C when I need vaccum or laser optics compatability.

Does outgas a bit when fluid, after that, nada... A salesman once said that large amounts went to Renton, WA, USA...  For wing leading edges on a four engined airliner. While I've never verified said claim, it should make German_EE happy... Henkel Hysol does make aviation epoxies, as well.

With care, I use it for insulating HV splices to 30+ KV, alternating layers of 1C, teflon tape, and heat shrink.

 


Steve

 

[aroby]

When it comes to glue what I'd like to hear from is someone from Boeing or Airbus. Both of them use large amounts of glue in aircraft manufacture because it's lighter than rivets and they get it right almost every time. So, what's their secret to fixing together two lumps of aluminum using just a thin film of glue?

I just bought some glue like that from a boat show in Fort Myers, FL.  Coincidentally the stand there was German Glue and the guy was German.  This stuff is amazing.  It is cyanoacrylate and has an accelerator and a filler.  He cut a a neoprene O-ring, then glued it in 2 seconds - I couldn't pull it apart.  Same with 2 metal nuts - a drop of glue between them and they couldn't be moved.

Web site is www.mabrisystems.com

[jwm_]

E6000 is a great glue. It is urethane based. It has become my goto general purpose glue.