P3D Re: Secured chips and "popping"

[Project3D@xxxxxxx]

In a message dated 17/07/98 23:04:06 GMT, Michael Georgoff wrote:

<< 

<Snipped>

 And, on the subject of mounting, I read somewhere (Fritz Waack?) that
 only one end of a chip should be secured (usually the bottom, instead of
 the top), as to allow for expansion if the slide is projected.  (Which I
 someday hope to do...) I note the RBT mount, as typically used. will
 only secure one end.  But, the Albion aluminum mounts were designed to
 hold both top and bottom, thus not allowing any room for expansion.
 And, some guides suggest both ends, and Reel 3D show mounting adhesive
 tabs on both ends.   I'd feel the chip is more secure it taped on both
 ends, and I don't want to get hundreds of mounts down the road, and upon
 projection, realize I've done it wrong... Any theories, comments, advice
 on top and bottom secured?>>

Back in the days before RBT mounts I used Albion foils with card covers on
both sides. I found that securing all four edges of each chip to the foil and
then laminating the cards to the foils using Scotch Spray Mount produced a
good stiff slide that resisted popping. 

I put this down to the tension in the chips that would be needed to pop.
Anyway, it worked most of the time.

Now that I use RBT mounts for projection, I still secure the chips in the
mount with litho platemakers' ruby tape (it is available in 6mm wide rolls).
This is because it is possible for the pin bars to move if the chips are not
secured. Tis, of course, would destroy my carefully set up window!

Bob Aldridge


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