Paperweigh bases re-visited

[Jerry Lawrence]

First, thanks to all who responded to my original post about how to charge for my collaborative work on some paperweight bases I made for a local glassblower. http://www.sawmillcreek.org/showthread.php?230061-Paperweight-bases

Now I have a new issue.....
After showing the bases at a national convention, the glassblower had a lot of requests for wooden bases affixed permanently to the glass paperweights. These would be made with a flat top, joined onto a flat spot on the bottom of the round paperweight. I've tried a few different glues, with the 2-part epoxy showing the most promise...but still not strong enough. A couple of the test pieces still separated. I tried scratching the glass at the point of contact to give the glue more grabbing surface, and I tried leaving it smooth...same with the wood (mostly cocobolo) but to no avail! Since these paperweights my have to be packed and shipped to customers, the glue needs to be strong enough to withstand the stresses involved in that, plus anyone picking them up, etc. Hopefully, no one is going to be prying on them or putting much stress on them, but if someone pays $500 for a piece, it should be bonded permanently! Also, since this is on glass, a clear drying glue is required.
Any suggestions would be greatly appreciated!
Thanks!

[Ted Calver]

I use something called plumbers goop to secure glass to wooden turkey calls. You might give it a try.
http://www.homedepot.com/p/Amazing-Goop-3-7-fl-oz-Plumbing-Adhesive-150011/100372167

[Shawn Pachlhofer]

I would try West System 105 epoxy resin with #207 "special clear" hardener. West System is not cheap, but it is a very good product.

this should give you a very clear, very strong finish.

if you're using cocobolo or any other naturally oily wood - I would thoroughly wipe down the glue surface with acetone prior to gluing.

[Steve Peterson]

thistothat.com suggests silicone as the best choice. It would provide a really strong grip while also allowing some flexibility for the different expansion rates from temperature and moisture.

Steve

[Paul Gilbert]

don't they mount rear view mirrors on the windshield with CA? If now I would use what ever is recommended for that job.

[Michelle Rich]

wood to glass is problematic. I've used stuff in the past that I got from craft supplies..I cannot remember the name..it was a flexible caulk.

[Thom Sturgill]

I think Steve has it right - silicon caulk can be clear. GE makes a clear 'Kitchen and Bath' caulk in small tubes which is available at most hardware stores for about $4.

[Ted Calver]

I had one reported separation using silicone on a glass to wood bond in a turkey call, which is when I switched to the Goop. No separations so far, but don't know if it remains clear. Seems like any problems would arise from someone picking up the paper weight by the base and turning it around and upside down. You would think the weight of the globe would stress the joint under those circumstances. In that case perhaps the Goop would be stronger. This is glass on cocobolo roughly 12" tall. Base is 5.5" wide. It gets fondled regularly and I used silicone to attach it about two years ago. No problems so far and the silicone is still clear.
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[Jeff Belany]

One idea that might help. I was told (when I worked with a 3M rep) that you can contact 3M and tell the 2 materials you want to stick together and they can recommend an adhesive. Might be expensive and have a quantity to buy, but it's worth a shot.

Jeff in northern Wisconsin

[Dan Hintz]

if you're using cocobolo or any other naturally oily wood - I would thoroughly wipe down the glue surface with acetone prior to gluing.

To me, this is likely your major sticking point. the same precautions come into play when I'm making pens with any oily wood... if you don't use acetone to cut the oils immediately before gluing, you're almost guaranteed to lose the bond.