Epoxy (or other bonds) + CR39

[krystian]

Hello,

Before posting my question, I read this thread on a related topic:
http://www.optiboard.com/forums/show...28&postcount=1

Since this thread was started back in November, I feel it's appropriate to post a followup question.


What sort of epoxies exist that will hold CR39 dietilenglycol bis allylcarbonate (ADC) together? Of course, the slower the cure the better. I've got a Third Hand/Helping Hand so it doesn't bother me. =)

Of course, this thread isn't limited to epoxy. Just epoxy was the first thing that comes to my mind. I'm curious of all sorts of solutions members have come up with for this problem.

In response to the earlier thread, some members posted they don't remember what they used to fulfill this task. I hope to create a resource thread of those and similar bond products. In the end Optical Lens Bond was suggested.

This thread is intended to be a followup inquiring about which bond products members used to fulfill similar needs of bonding lens (in the hopes that members in earlier discussion will remember and other members will discuss their experiances). I hope it will also serve as a resource to others who are looking to find a solution to this problem, by providing first hand accounts and pro/con discussions of varies items proposed.

[Jacqui]

I use a UV curing adhesive when making Franlin bi's. Will have to check the lab tomorrow to see exactly what the brand is.

[Chris Ryser]

In the end Optical Lens Bond was suggested.

Find it all at:

http://www.emsdiasum.com/Summers/opt...tech_data.html

[chip anderson]

I use two part epoxy that comes with the twin syrenge package. Gives me good working time. Will clean off polished surfaces without damage (with Acetone) and will not break at bonding point, even if you stomp on it after bonding complete.


Chip

I have now located the tubes for the product I use: ITW Performance Polymers, Rivera Beach, FLA 33404 Product : 5 Min. Epoxy System.

[krystian]

I use two part epoxy that comes with the twin syrenge package. Gives me good working time. Will clean off polished surfaces without damage (with Acetone) and will not break at bonding point, even if you stomp on it after bonding complete.


Chip

Last night I email contacted an epoxy/polymer maker, VersaChem. Their website: http://www.versachem.com/

I found their product stashed in the epoxy isle of an auto parts store.

I hope I'll find something out to share with the community.

[krystian]

Hello,

I ended up using an (Acrylic) Plastic Welder offered by VersaChem to bond my CR39 lens. It turns out that this is not an epoxy.* http://www.versachem.com/catalog.aspx?prodID=119

The adhesive reaches full strength cure in about 1 hour. Definately Use a Helping Hand if you are bonding parts together. A strength of upto 3500 PSI is advertised as the bond strength!

It bonds fine to CR39. I don't know about Polycarbonate, or other lens materials- if someone wants to try it, please let everyone know what you find!

The acrylic cures to a cream color which is not so great considering my lenses are rather clear. Oh well, it works, doesn't it? =)

TIP:
Be liberal with the adhesive. I was very liberal with the adhesive. After letting it cure overnight I just used nail clippers to clip off the excess resin.

* I contacted VersaChem and gave them the polymer formula for CR39 so that way they could match me with the best adhesive for the job... you might want to do this if you want to shop around for adhesives, or if the above product becomes unavailable. http://www.df.unibo.it/macro/intercast/charact.htm

[krystian]

I had a pair of rimless glasses I used in this (lenses are held in place by screws which connect to ear brace)

The fracture I had in my glasses: There was a fracture where the screw met my rimless lenses.

Therefore it wasn't a concern that this would affect my main vision if repaired. To give you an idea of how peripheal the fracture was... When I have the glasses on, I can't even see the fracture.

I called around to some optical retailer shops in my area (I made sure that these shops did repairs too) and none of them would do it. Here's what they said (many different opticians), so if you guys ever run into any of these statements... don't be discouraged. You'll just have to do your homework to find the right adhesive.

1. Epoxy will melt the lens.
2. Epoxy wouldn't hold the lens
3. Told me the law prevents opticians from using epoxy to repair lenses.
4. Liability issue. Safety issue.

So what I'm trying to say: If you have to repair your lenses, this is definately going to be a do-it-yourself project. Don't expect to outsource it. =)