Plastic Lens Insertion

cellulose acetate

• amount of heat: minimal heat until pliable

• heating methods: hot air best

• how to shrink material: plunge in ice water

• notes: standard material used in most plastic frames

cellulose propionate

• amount of heat: cold snap if possible, use minimal heat if not possible

• heating methods: low heat setting on air warmer

• how to shrink material: N/A

• notes: heat only a little at a time

nylon

• amount of heat: use hot water

• heating methods: hot water

• how to shrink material: does not shrink

• notes: to retain adjusted shape, hold frame in desired shape until cool

carbon fiber

• amount of heat: none to minimal, cold snap

• heating methods: hot air at low temp if necessary

• how to shrink material: does not shrink

• notes: types vary, thus so will heat & insertion techniques

polyamide

• amount of heat: no heat, cold snap

• heating methods: hot air for temples only

• how to shrink material: shrinks slightly when heated

• notes: after insertion, loose lenses may be tightened with slight heat

polycarbonate

• amount of heat: none

• heating methods: cold snap

• how to shrink material: does not shrink

• notes: does not adjust

optyl

• amount of heat: high heat, heat until it bends under its own weight

• heating methods: hot air, high temperature

• how to shrink material: does not shrink with heat, expands with heat & gradually returns to size as temperature cools

• notes: returns to original shape when reheated, quick cooling stops the shrinking process & results in loose lenses