UV Activated Glue - Any Good?

Baking Soda soaks up the superglue quite well. It’s easier to use than the steel powder. I’ve used it if there is some of the original plastic left to bond to. Useful for other stuff too.
But the resultant solid is not as sturdy as using powdered steel dust (at least I’ve convinced myself of that) . These crappy little mounting posts are subject to both compression, shear, and extension stress.
JB putty would work great, but it doesn’t stick to plastic as well as regular JB or superglue.

Once the joint starts to go, unless the user takes remedial action quickly, the little posts crumble and you’re are left with the little brass inserts unsupported by anything other than the surrounding components.
This user had the screen duct taped together to keep it from coming apart. The hinge was forcing the screen to pry itself asunder.
On this particular laptop the hing actually has a component that floats unsupported and acts as a lever to the hinge mounting points. I made a support to brace it from below so it doesn’t have a chance to flex as much. Popsicle stick shaved thinner and cut to shape did the trick.

Dell, in it’s wisdom, peens over the threads on the hinge pin. Making nearly impossible to disassemble without taking the whole frigging thing apart.
And don’t get me started on cable routing through the hinge area.

Dell isn’t the only company that has great ideas. There are some Toshiba laptops that are great PCs. I’m typing on one now. If the keyboard goes, the replacement is relatively expensive as laptop keyboards go. BUT, it’s attached to the top clam shell with plastic studs melted into the mounting holes on the keyboard.
So to remove the old one, you melt the studs with an iron. Shape them us as best you can so the new KB will fit. Then hope you have enough plastic to work with to secure the new KB. Or try superglue and baking soda :smiley:
How do you quote a repair like that? Well, if it works, it will be 2 hours in labor plus parts. But it might not work. And I won’t know if it works till after I’m done.

Good to know about UV not liking to stick to plastic. That’s key to doing this type of repairs.
All the Best,
Jeff

The light has to reach the UV glue, so bonding opaque surfaces don’t work.
I’m sure, just like all glues, there is a wide variation in quality.
I have a ‘cheap Chinese’ small kit, brand name [Visbella]; glue and a small UV light.
Some things it worked a treat for, due to the ability to ‘freeze’ the glue quickly.
Some things it didn’t stick to very well at all. Doesn’t do too well with plastic….little does.

When the small tube ran out I went Amazon shopping for replacement. Reviews are all over the place.
Finally bought a bottle called [Damned Good UV Glue]. Yeah, that’s right.

I think the “glue” may be better…maybe. BUT, the little UV light with the kit doesn’t work well to kick it.
Luckily I have a really strong UV light that does seem to work.
Weird, you’d think any UV light “designed” for the glue would work.

It does seem to have……some……useful applications. Not nearly as good a glue as epoxy or JB Weld, but it does cure almost immediately which those glues do not.

Le sigh.

I miss full magnesium chassis Thinkpads.

Oddly enough, this Dell has a metal lid. Naturally the hinge is connected to a plastic internal part that is held to the lid with snap on grabber thingies….

Duct tape for the lid hinge?
I have a Lenovo ultralight that I replaced the battery. Battery was a thin ‘plate’ the size of the whole bottom. Broke damn near ALL the stupid little plastic clips getting the bottom off. Now held on with electrical tape. Pissed, but good enough. Jeez I miss simple little screws holding things together.

New production technique > snap it together….fast. When it requires repair……don’t. Throw it away and get a new one.

First UV glue I tried was Norland N0A61. Bought it specifically to glue lenses into bezels. Unfortunately, the UV light had was no good. I found the best way to cure it was to leave it outside in the sun for an afternoon. Even then, the glue never seemed that strong. It definitely wasn’t a replacement for super-glue for regular hobby projects.

First cheap consumer UV activated glue I tried was Fiberfix, which I found at my local grocery store.

  • It came out of the tube like super glue gel. It is a cyanoacrylate adhesive … basically super glue. However, when you shined the little LED light in the back of the tube on it, it cured instantly (1-2 seconds). Even with no UV light it would dry and harden when exposed to air just like super glue.
  • This was a fantastic glue. It was capable of gluing things no other glue I had could. For example: I had a small glass statue that had a couple glass figurines break off. Pieces were missing. I needed a thick glue, capable of holding glass at an angle and able to work without a flush fit between the broken pieces. The Fiberfix worked perfectly…. the cure was so fast no vise was needed. I was able to simply squirt out some glue, hold the piece in place by hand, and then use the UV light to instantly cure it.
  • If I could get Fiberfix like this again it would be my favorite glue.
  • Unfortunately, that first batch of Fiberfix was a bit of a fluke. My grocery store stopped carrying it, so I went to a hardware store instead. Half the tubes I got from there were unusable out of the box (all glue solidified to rock solid inside the tube). The other half the glue came out runny instead of like a gel. The runny glue was still usable… I could squirt some on a disposable surface and then shine the UV light on it for a few seconds to partially cure it into a gel, then move it onto my project with a toothpick. But this wasn’t as convenient or as fast curing as the original batch.
  • I also tried ordering some Fiberfix from Amazon, but all tubes came solid and unusable out of the box.
  • Even when Fiberfix worked perfectly it had issues. Each tube cost $10. And after opening, the glue tended to solidify in the tube if not completely used in the next month or two.

I still like UV cyanoacrylate glue though since I can use it like super-glue and with the added benefit of curing in less than 10 seconds with UV light when needed. However, I no longer use Fiberfix due to the aforementioned issues.

Nowadays, I use Surehold Helios UV glue from Amazon. It comes in a black bottle that reliably keeps the glue liquid for many months after opening. And unlike with Fiberfix, every batch I’ve gotten from Amazon came liquid out-of-the-box.

It’s my go-to glue for any project where I don’t want to spend a lot of time waiting for cures. And it even works where the UV light cannot reach all the glue, since exposed glue will dry within a couple hours just like exposed super glue.

One other tip: Cyanoacrylate adhesives, including super glue and these UV activated cyanacrylate glues do not bond well to most plastics.

To fix this, buy Loctite Plastics Super Glue .

The package comes with a tube of super glue, and a plastic activator pen. Feel free to use or discard the glue. It’s basically just regular super glue. What you want is the activator pen.

To use the pen simply draw on both surfaces to be glued with it, then wait one minute. After that, apply ANY super glue, including these UV cyanaocrylate glues. In my experience, the pen makes any cyanocrylate adhesive bind to any plastic, including rubber.

Once you use the pen and then apply the glue, usually the plastic will break before the glue detaches. The activator pen is awesome!

you have to have a rough surface but not entirely bumpy

it can;t cure down inside a crack or break

it doesn;t cure in thick layers

the lights that are powered by a coin cell to cure it, are terrible

it can;t cure inside uv-proof plastics [which is most of them] or most glass
so it kind of has to be on the outside

on the plus side—
it does cure fast
it is moderately sticky and strong

so i would agree it is ok for a few things but pretty limited

i can;t see that laptop hinge repair working

but do let us know

I’ve done maybe 5-6 of these using just superglue and the steel powder. Four held (as far as I know) as long as the user was careful. One needed the full JB fix after it failed. But after that there is no going back as it’s a permanent fix with no way to take it apart…
I’ve done a few where I drilled through the case and used a screw and bolt. Very steampunk.

After putting this one together like 5 times, I finally got it fit together correctly…
Fired it up today with an new SSD installed for a new OS install.
Screen had fingerprints n it.
Wiped it down. Still there. On the inside of the touch screen glass… Well crap, I gotta take it apart again. But not for a while. I’ve got way too much time on this one already.

A lot depends on how the mounting points are built. Some are hopeless and I go straight for the JB full goop repair.
JB will hold as long as the surfaces are roughed up and cleaned really well. It ain’t never coming apart again.

I do this mostly for grins as the cost in labor is usually more than the laptop is worth.
As the super slim designs become the norm, repairs are getting harder for small shops to do.
And don’t get me started on Apple products….
All the a Best,
Jeff

Quote:
To fix this, buy Loctite Plastics Super Glue .

The package comes with a tube of super glue, and a plastic activator pen. Feel free to use or discard the glue. It’s basically just regular super glue. What you want is the activator pen.

To use the pen simply draw on both surfaces to be glued with it, then wait one minute. After that, apply ANY super glue, including these UV cyanaocrylate glues. In my experience, the pen makes any cyanocrylate adhesive bind to any plastic, including rubber.

Once you use the pen and then apply the glue, usually the plastic will break before the glue detaches. The activator pen is awesome!
[/quote]

Happen to know what this activator is? Some say it is n-Heptane, found in rubber cement thinner.

Just putting this out there…

I would be tempted to use Loctite Hysol 9462. Anything I’ve glued with this stuff has NEVER come apart.

One sneaky trick for precision work is to put a leur-lok dispensing needle on the end of a “taper tip” static mixer nozzle.

yes, the one i had was very good, i bought a tube at home depot a while ago, it had a uv on the other end of the tube, and i can’t find it anymore,
and i did use it for exact same purpose, in laptop repair, those broken posts with brass inserts, it was perfect for the task, no mess, almost instant bond, and strong hold.

If you knew what type of plastic it is solvent bonding might be an option. I used this method to build an enclosure for a pd trigger board for a cable to power a small 12v portable tv using a 30000mAh power brick. I couldn’t find a plastic enclosure the right length so I cut two down to give me the proper length. A little sanding on the cut ends of the boxes and lids for a nice tight seam, a drop of acetone from a glass eyedropper, a little brushing across the seam with an acid brush and I had a nice strong joint.

A bit of the same plastic shaped to replace what’s damaged and a bit of appropriate solvent and problem solved.

Another option might be use of a hot air station and plastic welding rod to rebuild the damaged area.

I just glued the plastic hinges on my Samsung lap top. Used crazy glue and baking soda. I had to limit the build up because of clearance issues but seems to be holding well so far KOW.

There are three categories of glues; tacking, structural and sealing. You need a structural type glue to fix broken hinges. Super or cyanoacrylate glues are tacking glues and have no impact or flexing abilities regardless if some say they do. Two part epoxies either the 5 minute or regular varieties are much better for this type of application. UV epoxies are just an expensive option to the two part epoxies, they are are normally used in the electronics and dental industries where a form and instant set requirement is required, but the down side is that if the light is not intense enough it will not cure properly. Seen it many times in the electronics industry where UV epoxies ruined many expensive motherboards when the UV bulb decreases in intensity over time and the glue would not set properly and the product made it to the customer with a runny glue.

I am usually not a fan of crazy glues either but in applications where build up is limited, epoxies aren’t so great either. I don’t remember a hair line crack in plastic ever being successfully glued in high stress areas unless being able to add material around the crack. I doubt any glue will work for long in my case because the crack is in material that is only 1/2” wide x 3/16” thick and all the weight of the screen is on two of them. I’m surprised they didn’t crack sooner. The hinges rotate into the body with little clearance so I was only able to add a slight bit to them on the surface. Time will tell but I was impressed how the baking soda allowed me to thicken the joint and seems to adhere well.

pennzy, Yeah, it’s astounding how poorly some of the hinge arrangements are designed.
I think your baking soda / glue fix will work if you don’t get too frisky with the lid.
It helps to loosen the hinge joint a bit so not as much pressure is needed to open and closed the screen. I always add a drop of lube where the hing parts move against each other.

If there is enough of the structure left, I try to do a rebuild of the mounting points so the thing can be used with the OEM mounting attachment hardware. This lets the hinge come apart again in the OEM manner.

Most hinge attachments seem to have a flat metal plate the mounting screws go through to attach to those dinky brass inserts pressed into the internal plastic. Superglue with some additives works remarkable well. Whatever plastic they use inside laptops seems to be the kind that superglue sticks to firmly.
Once the plastic is too far gone, it’s not possible to build it up again with sufficient strength to hold the inserts worth a darn.

Then the only recourse it to scuff up the hinge metal plates and the plastic mounting area. And try to permanently glue the hinge hardware to whatever is left inside. So you get the full area of the hinge plates to hold the joint. Instead of just the dinky brass inserts. Naturally this is never coming apart without serious damage to something inside.
The slow set JB-Weld is the best stuff I’ve found so far for doing this. Some of the gunsmith type of bedding gels work well, but I never seem to have any when I need to do one of these repairs.

Sometimes one of the hinge screws is aligned with or uses one of the screws that attach the bottom or some other exterior trim. If there are no electronics in the way, I’ve drilled through the outside of the case and used a screw and nut along with JB to secure the hinge plate to the case.

Metal duct tape is handy for holding trim or body parts together after the dinky mounting tabs have popped off from being pulled apart too many times. Looks better than the gorilla tape.

Once I took pity on a user who had no funds for a new computer and I simply glued the screen to the body with a strip of metal bent to the appropriate angle. Never to move again.
Quick, dirty, but it kept her going till the last semester was done and her final papers turned in.

In the early days of desktop computer building, lots of stuff didn’t fit like it was supposed to. A hot glue gun was part of the kit.
All the Best,
Jeff

A lot of good ideas there Jeff. I especially like the last one. :smiley:

I really appreciate you sharing your insights and experiences with hinge repairs. Your approach to using superglue with additives for hinge attachments and even resorting to metal duct tape when needed shows a true DIY spirit. While I haven’t personally tried UV activated glue, your description of its potential effectiveness in certain situations is intriguing. Have you ever considered exploring different adhesive options, like mod podge fabric? I recently stumbled upon a tutorial, and it seems like it could open up a whole new world of possibilities for your repair projects.

UV glue will not work for fixing brass thread inserts of laptops, I tried. failed big time. As it was mentioned correctly it does not stick well to plastic, and you can not get uv thru non transparent parts.
I used jb weld epoxy, it worked better but still did not hold up overtime. If the post where that brass insert was mounted broke apart, almost nothing you can do as far as glue, exsept soda and crazy glue, but you will need to figure a way how to contain it, basically you need to do what concrete workers do when they pour a column, build a mold around it. make sure you plug the threaded hole with something so soda and glue will not get there, do not put screw in there it will be impossible to remove, you will destroy the part you just fixed trying to unscrew it. I used playdoh