Adhesive to bond slides for "micro-phototank"

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uglyjeep
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Adhesive to bond slides for "micro-phototank"

#1 Post by uglyjeep » Thu Dec 13, 2018 11:13 pm

I need to put together a few more mini/micro phototanks together for fish/aquatic invert examination and photography. I've already built 2 using silicone, and have found that there isn't sufficient strength to keep it all together well enough to withstand transport (without overly intrusive bonds). I'm wondering if anyone here has suggestions of what adhesive to use for bonding standard glass microscope slides together. The bond has to be liquid tight and strong enough to hold up to field use (they will be transported in a padded case).

Here's a rough model to give an idea of what I'm putting together. The slides are 3"x1" glass (the end sections are cut down to ~1").
Image

MichaelG.
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Re: Adhesive to bond slides for "micro-phototank"

#2 Post by MichaelG. » Thu Dec 13, 2018 11:40 pm

Many car rear-view mirrors are bonded with special UV/Visible light-curing 'glass bond' adhesive.
... That should be strong enough.

MichaelG.
.

Edit: This looks worth studying
https://www.intertronics.co.uk/product/ ... adhesives/
Too many 'projects'

Hobbyst46
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Re: Adhesive to bond slides for "micro-phototank"

#3 Post by Hobbyst46 » Fri Dec 14, 2018 9:29 am

IMO, silicon rubber adhesives like RTV are the best for your purpose. Their advantage is that they are sealants, whereas UV-curing adhesives are mechanically stiffer, but are not sealants. Note, though, that the full curing of RTV takes time: at least a day or two, depending on the temperature. Also, full curing is critical because otherwise, these adhesives release acetic acid which is harmful to certain aqua life.

uglyjeep
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Re: Adhesive to bond slides for "micro-phototank"

#4 Post by uglyjeep » Fri Dec 14, 2018 9:29 pm

Hobbyst46 wrote:IMO, silicon rubber adhesives like RTV are the best for your purpose. Their advantage is that they are sealants, whereas UV-curing adhesives are mechanically stiffer, but are not sealants. Note, though, that the full curing of RTV takes time: at least a day or two, depending on the temperature. Also, full curing is critical because otherwise, these adhesives release acetic acid which is harmful to certain aqua life.
For the size of these phototanks I haven't been able to get a bond that I feel will be strong enough, but remain minimally intrusive for photographs, using silicone. I'm looking for a bond line no bigger than a few mm and at that size the silicone separates from the end panes easily (even after a week of cure time).

I've asked our purchaser to look into samples from Dymax (I work in aerospace mfg), but in the meantime I'm going to try a few clear 2 part epoxies, and a glass "super-glue". My main concern using these will be moisture resistance.

Hobbyst46
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Re: Adhesive to bond slides for "micro-phototank"

#5 Post by Hobbyst46 » Fri Dec 14, 2018 9:55 pm

Glass super glue is being marketed for fixing of car windows, so I guess it is fairly resistant to moisture.

PeteM
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Re: Adhesive to bond slides for "micro-phototank"

#6 Post by PeteM » Fri Dec 14, 2018 10:31 pm

Are you trying to illuminate and image through the v-bottom of the vessel? If so, you might try a re-design so a glue line isn't in the way?

uglyjeep
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Re: Adhesive to bond slides for "micro-phototank"

#7 Post by uglyjeep » Fri Dec 14, 2018 11:43 pm

I'm viewing from the angled sides (the angle helps cut reflections). I'm not so much worried about light being blocked from the bottom bond, just how much of the adhesive is on the sides (the meniscus?).

I have been using a glass petri dish for vertical viewing. However, to do this the fish has to be euthanized or heavily sedated (which often results in mortality for juvenile and larval fishes). By viewing horizontally, I'd like to be able to use minimal (or no) anesthesia. The majority of fishes I work with are endangered, and I'd prefer to avoid mortality for this project if possible. Though we are covered under a Mexican scientific collection permit, we don't have a CITES permit to bring any specimens back to the US.

I do have some time to get this worked out. I'm just working out methods and equipment before my field season starts again. It wouldn't be a major issue if it didn't work either - any specimens I do collect could be cataloged at the UNISON Hermosillo.

That said, I am also trying a simpler design built using 2 slides that sandwich a notched section of acrylic. This setup has more than enough surface area for silicone to hold very well.

PeteM
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Re: Adhesive to bond slides for "micro-phototank"

#8 Post by PeteM » Sat Dec 15, 2018 3:58 am

You might try masking tape near the bottom of the "v" to minimize the glue climbing up that "meniscus"? A bit of glue over the tape will usually pull right up.

Something else you might try is transferring a bit of silicone seal to a disposable syringe - you'll have much better control in placing a small amount inside and out of the joint.

MicroBob
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Re: Adhesive to bond slides for "micro-phototank"

#9 Post by MicroBob » Sat Dec 15, 2018 10:31 am

There are car front window repair systems - this glue might be an idea.

You might keep your fish vertical and put the microscope horizontal. You could use an old inclinable horseshoe microscope or a stereo microscope on a universal stand for this, depending on the magnification you need.

Bob

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