UV Liquid Plastic Adhesive Refill 10 mL - Twin Pack, 6121830ES

I am an RC model builder and bought "RapidFix UV Liquid Plastic Adhesive Refill 10 mL - Twin Pack, 6121830ES"for $16 and "Bondic Refill 4 Gram Liquid Plastic Cartridge UV Adhesive Glue (Pack of 2)" for $10 to test.The test was gluing a toothpick to a plastic eyeglass lens. The lens was cleaned with alcohol before the tests.Bondic is slightly thicker than RapidFix but both maintained a dot shape and cured in 30 secs with a 51LED 395 nM Ultraviolet flashlight. Both had a very slight yellow tint that was only apparent on white backgrounds. The tint is not apparent on color or off-white surfaces. The RapidFix glue fluoresced under UV light both during and after curing. The Bondic had a nice metal applicator needle. Both are "refills" but can be used without the original product. They had no noticeable smell and the containers sealed well.The RapidFix dot of glue pulled loose from the plastic lens on all 3 tests. The Bondic dot of glue stayed on the lens and toothpick broke first on all 3 tests.I was able to scrape both types of glue off of the lens with my fingernail in an additional test.A super glue dot on the lens did not maintain a dot shape and did not cure. After 5 minutes I cured it with Insta-Set but the glue dot hardly stuck at all to the lens. Both UV glues stick better to this type of plastic than super glue.A relatively weak 1200 ft/lb 5min epoxy stuck better to the lens than the other glues but did not dry clear due to bubbles created by mixing.Conclusion: Both UV glues stuck better to smooth plastic than super glue but not as strongly as epoxy. They are very convenient glues in that they do not run and will stay liquid until cured by UV light. I like the cost per gram and fluorescence of RapidFix. It might have some interesting uses in black light art. Bondic was stronger during my tests and I will probably buy it again since strength is my primary need.

I first gave this 5 stars but now I am here to update it to a 4 because there are a few issues: You never know exactly when its cured in bigger jobs. Such as in I glued a custom made LED light fixture into place using this and later found some of the glue hanging from the unit. What is CLEARLY needed here is a pigment that turns white when the glue is hardened, like with every other household glue you can tell by a color/opacity/translucenscence change alone. With this you can not.Matter of fact I'd give it 3.5 points. I haven't tested its strength yet but it never really hardens. It turns silicone caulk like which is fine for some jobs but I would like a version with a binder added so that this stuff turns rock hard like the stuff the dentists use on your teeth.edit: PS: I followed Drew's directions and bought this refill kit to get more product and the UV light separately with more LEDs and more power. How you could ever grind this stuff would be beyond me -- I wouldn't even try as its rubberyness would clog the sanding grit.I also now realize the reviews I listened to and read talked about SMALL repairs like the threads lens from a camera. At this small amount you are not going to notice much rubberiness.I, however, used it on adhering a LED light to about a 1 gallon plastic container (a used protein powder container) and it did hold better than hot melt glue (which failed after a week or more, probably heat-related and I probably should have used the higher heat hot melt glue because LEDs put off some heat and kicthen ceilings right above a stove can get a good blast of heat) and it is still holding. Been a month or so.Then I used it on a passport holder that went around my neck. Instead of the elastic nature of the products working together it fell apart hours later beause this glue does not penetrate very deeply, if at all. I am more used to working with standard wood glue (which is basically colored Elmers, FYI) and that penetrates well enough that a well made glue joint is stronger than the wood itself -- I've never had a fresh one fail.Would I buy this product again? Probably not, it's not so excellent for my purposes and I will likely use the 99 cent two part epoxy I bought half a dozen pkgs of from HarborFreight.Com to repair the around the neck passport holder. (The holder is new BTW, I just cut the cord because it was WAY too long and tangled in my hat and clothes or earphones/headphones/headband too often.)I am really suspect of the claim it gets "rock hard" to ANY degree as IF UV cured this to that the kitchen one (even if my light got non UV LEDs) would have gotten enough of mother earth's sunshine to make it "rock hard" and it is clearly still rubbery.In fact calling it a glue I think it is a misnomer. This is more like butyl rubber caulk, silicone and not even as hard as construction adhesive like PL200. It may be right for your uses but it was not right for what I had hoped it to be.IT DOES fluoresce well so you can see where you have put it but even this is odd as sometimes I needed a regular flashlight to see where the clear glue went and then change to the UV flashlight to cure it. If you own a decent set of clamps this is probably not for you with maybe the exception of hobbylike uses.

I used the product to repair broken plastic glasses. It worked very well and very rapidly upon first use. When I tried to make another repair a week later, after the container had been opened, the material would not cure properly and stayed gummy regardless of how long it was exposed to UV light. There might be a problem with the material once exposed to air.Review addendum: I increased my rating from a 2- to 4-stars. This product, when fresh, does a great job and sets up hard and fast. I really like the feature of the UV light cure. That allows me to control the timing of the set. However, I stand by my claim that once opened and exposed to air the UV light does not cure the material as fast or as solidly. So, just plan this as a one-day use item ... after that, don't expect great performance. For some repair jobs this product is very handy and worth the price. For instance, I used it to repair multiple lengthy cracks in the plastic bowl of my old food processor. It worked like a charm and saved me from having to get a replacement bowl or a new food processor.