Bill Maddux wrote: >I have been following your thread re adhesives with interest. >(For what it's worth, I concur in the view that silicone has the >edge over epoxy for gluing metal to stone --- as well stone to >stone --- based on my limited experience in dialing and in >stone carving.) >..... an important property of an adhesive bond, may at >times be that it can be readily parted, should need arise. The >consequences of failure in this might not be so dire as those my >uncle invoked, but there are many possible reasons for wanting >reversible adhesives. In the actual fabrication of dials, thin metal >stock must often be supported, or held without distorting it with >clamps, in order to perform machining, grinding or polishing, and >very importantly, supported and 'backed' for engraving, chasing, >or 'repoussé' work. Many of the more desirable alloys are non- >magnetic, so magnetic chucks are not an option. Traditionally, >beeswax and rosin, pitch, sealing wax, stick shellac, and such >have been used.
>.... what are >the odds that there might be good reason to 'un-set' a dial within >its lifetime? As present-day humans, we are a mobile and restless >bunch. We might move, and wish to take the dial with us. The >chosen site might become unusable in the face of subsequent >building, landscaping, or other activities. Accidental damage, or >vandalism, could make it necessary to un-mount a dial and take it >into a workshop for repairs. > >In the case of silicone, (and absent Tony's adjusting screws, with >only John's wooden shims to contend with) a long, slim, serrated- >edge bread knife might do the job. Otherwise, a length of >bandsaw blade, mounted in an improvised, old-fashioned-type >saw frame, (the 3-wooden-piece kind, with a twisted-cord >tensioner) might be used to provide the needed clearance and >cutting span. Epoxy would almost surely be more difficult to >deal with in such an instance. Hello Bill (and others) I've always been worried about that too: that if I install a sundial too permanently, it would be impossible to move it should the need arise. Here's an idea on how to remove a silicone attached sundial from its pedestal. I don't know if it would work because I haven't tried it. Maybe the silicone could be cut (sliced) using a very strong but very thin piece of piano wire moved back and forth (Like a cheese cutter or dental floss). Did you know that there are machines that cut stone using wires covered with diamond dust? A wire could be made any length and might be easier to use than a blade or saw. Just a thought John
