5 years, 11 months ago-
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The chemical: trimethoxysilanes. It has some pretty nasty warnings on it and it is displayed with the super glues.
Never used it. What advantage do you anticipate? Also, the warning “Not Recommended for applications where at least one surface is not porous” would seem to preclude use for dopping.
Doesn’t sound like a good choice, per what Al said. The only difference between brands of CA MIGHT be some differences in purity, but any of the leading brands will work well so long as you follow the directions closely. Hot Stuff and Loctite Professional grade have never failed me so long as I run a dab of fingernail polish around the join to exclude water, which can and will force a join to fail at some point.
Most join failures are due to improper dop or stone preparation, water attacking the join, some one pressing on the quill rather than the stone, poor storage of the glue, etc.Max bond strength can take 72 hours, but 80% of bond strength is approached in under ten minutes, according to the chemists at LocTite. Glue it, wait a few minutes and really try to pull it off. If you can’t, you’re good to go.
Wayne
The warning is as follows: “May be harmful if inhaled or swallowed. Methanol is produced during application and curing, which may the nervous system causing dizziness, headache or nausea. Use in well ventilated area. Do not breath vapors. Avoid eye and skin contact…”
Reactive silanes are more typically used as adhesion promoters or couplers. The silane reacts with metals and especially water in metal oxide coatings and pins itself to the substrate. Some silanes combust spontaneously when dumped in a lab sink. The methoxyls or other organic groups are compatible with the adhesives system used.
Methanol is often used as a carrier solvent in silicone systems. Anyone who has used a platinum catalyzed silicone rubber has smelled it when adding the catalyst. The methanol warning is needed because drunks used to destroy their optic nerves, or died, when trying to drink it, but in trivial sub-gram quantities the MSDS is scarier than it needs to be. Lawyers, you know.
Thanks, Wayne. I like the tip on using fingernail polish around the edges. It had always been a race for me to finish something like apitite before the glue gave way. 🙂
sorry guys i just go to a hobby shop and buy their gap filling purple CA used on model planes and bottle of quick setter and only use on table flat area to cut bottom first then transfer to green wax and any time i have a stone waxed break loose i use this gap filling CA to put it right back in correct pattern position. mike zinski gemmakermz@cs.com
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