Chapter 8 Flashcards
What does it mean for a frame to be trued
It has been brought into standard alignment
Truing a frame intends to
Ensure that adjustments are response to physical characteristics
Before additional adjustments can be attempted, frames must be
Brought into standard alignment
What’s the general rule for standard alignment
- Begin with bridge
- Endpieces
- Temples
Handling the bridge first helps to
Eliminate having to go back and realign parts
What frames always need to be heated to be aligned
Adjustable plastic frames
Metal parts do not require heating unless they are
Covered in plastic
Standard plastic frames are made of
Cellulose acetate and cellulose propionate
What heat may be used to align frames
Either forced hot air or a “salt pan”
Salt will stick to a frame that has been
Cooled in cold water
What is an horizontal alignment
One lens is higher than the other
What is a vertical alignment
One lens is pushed back from another
What can cause horizontal alignments
Either a rotated lens or a skewed bridge
What is x-ing
A vertical misalignment in which the front frame may be twisted so that planes of two lenses are out of coincide
X-ing causes for temples to
Be out of line with one another
