Anybody using UV cured adhesives for acrylic ?

[Larry Bratton]

I just finished up a little project that cried out for optically clear joints on clear acrylic. I was using the traditional Weldon #3 and #4 adhesives. When the chemical reaction would occur, you could see the area where this took place. I also tried an adhesive made by Acrylite called Acrifix 117, which is a good adhesive, does not craze as badly and is free of methylene chloride. Not as fast as #3 but I did get good results with it although not totally clear. Acrylite also suggested a 2 part adhesive such as their 190 for museum quality, but I suspect this would be very slow and hard to work with. Maybe for a one or two item project, but not for larger quantities.

While researching adhesives, Mike Null had given me a link to a LocTite product that is UV curable. After doing more research, I found several products out there that will work with acrylic and will apparently deliver optically clear joining. I found that these adhesives are pretty common and can be cured very rapidly with a UV light with a wave length of 365nm or so.

Is anyone here using this type of adhesive? If so, which ones are you using and what equipment are you using to cure them?

[Mike Null]

Larry

I only know of one person who has tried this. His name is David Takes and he looks in here now and then. You can pm him though.

I have some on hand but haven't tried it yet.

[Larry Bratton]

Which adhesive do you have Mike? What do you have as a light source? I read in another forum for people that do glass crafts that a UV light with a 365nm wave length is required for these adhesives. There are medical and dental adhesives that are in the 430 to 470nm range. If I understand it correctly, the photo sensitive catalyst has a specific range and I suppose would not set if it were out of range. Some say a regular old blacklight will do the job but I think they vary in intensity. Some of these so called "industrial" light sources are expensive...$1000..$2500 and up, a little pricey for my little operation.

[David Takes]

Hi Larry,

I've never been thrilled with the look that the solvent-based adhesives produce when gluing acrylic. There is always an issue with bubbling, a crazed edge, or something. This is why I started experimenting with UV adhesives. To make a long story short, I have been using a UV adhesive I imported from China with a larger crystal order. I have also used a UV adhesive from Ikonics Imaging that is used for glass. In either case, I cure it with a hand held Spectroline EA-140 UV lamp. As you mentioned, it is a 365nm wavelength light source. These are reasonably priced and can be found on Ebay on rare occasions.

Using UV adhesive for adhering acrylic is an acquired skill. You need to expose the glue for a short period to where it just starts to grab, then clean up the excess. You do not want to do the cleanup after you have over-exposed the excess glue.

One other factor to consider is that some acrylics have UV inhibitors in the substrate. You will not be able to use the UV-cure adhesive with these acrylics.

In the two years that I have been using the UV-cure adhesive I have only had one award brought back because of adhesive failure, but that was because the customer dropped it. it would have had the same result had I used acrylic solvent adhesive.

[Steve Clarkson]

Larry......I've been very happy with Max1......it dries much clearer than Weldon.

[Larry Bratton]

David:
Thanks very much for the reply. I found a similar Spectroline unit on Ebay that is a 365nm lamp. I think the number was E-14 for $50 bucks. I bought it and I think it will do the job. Acrylite has a UV curable adhesive that works with their products. They sent me a chart that was helpful. I am going to give it try. I am so tired of dealing with the appearance issue when trying to glue edges with solvent cement that I am anxious to find something else that works better. Thanks for the tip.

[Larry Bratton]

Larry......I've been very happy with Max1......it dries much clearer than Weldon.
Thanks Steve, that stuff should be good if price is any indicator. Looks to be about $1 a gram plus the accelerator. Maybe a better price somewhere besides where I looked online. Guess you pay for what you get.

[Steve Clarkson]

I agree, it is very expensive......but it will literally glue anything to anything....

[Scott Shepherd]

I have not used the UV for acrylic, but I have glued a a number of pieces with the UV, glass on glass. As David mentioned, from Iconics. I use a standard shop light fixture, 2 24" bulbs. I bought the black light bulbs from lowes, along with the fixture. Probably $40 in everything. I sit it on the table, bulb side up, I place my project on top of the bulbs. I turn it on, sit a cardboard box over it, come back 15 minutes later, it's done. It works beautifully and gives a beautiful joint.

[Larry Bratton]

Steve, I have been working on figuring out which adhesive might be best for acrylic. This is the one I came up with, Dymax 3099 from Ellsworth. 1 liter bottle is $214.00.(that would last a long time, about = to 2 pints of Weldon) Your black light should work with it. http://www.ellsworth.com/display/productdetail.html?productid=2192&Tab=products

[Terry Swift]

Although a bit expensive, wouldn't a Crystal Keepsakes Curing Unit or something similar do the same thing. I'm with Steve on the homemade and cheap versus buying something that's close to $1k.

[Larry Bratton]

Although a bit expensive, wouldn't a Crystal Keepsakes Curing Unit or something similar do the same thing. I'm with Steve on the homemade and cheap versus buying something that's close to $1k.
Terry, I suspect so. But like you said..that thing costs a $1000.00. I bought a hand held unit off Ebay of the proper wavelength for $50. Steve has a good idea for a bigger size. It needs to be in the 365nm range which is the workhorse wavelength for UV and will deliver adequate intensity.

[Michael Hunter]

Careful with the LocTite UV adhesives - some of them need two different UV wavelengths (UV-A and UV-B I think) simultaneously and so can only be set properly with a special (i.e. expensive!) light source.

I use an optically clear LocTite (sorry, can't remember which number) to glue glass to metal.
Using a sun-tan lamp (UV-A only???) for curing leaves the glue edge which exposed to the air sticky. (Not a problem for this particular application, but annoying).

I did look into blacklight lamps, but although most of them do produce both wavelengths, in the commonly available ones almost all of the UV-B is filtered out by the lining of the tube.