Why plastic or acetate frames sit at different heights

01 · FRAME ALIGNMENT

Is the front twisted?

Start by checking the acetate front itself.

Heat or pressure can create subtle front-back or vertical differences between the rims.

If you adjust only the temples while the front is distorted, you may simply compensate for the wrong reference.

For a plastic frame with unequal left-right height, first determine whether the entire front lies in a consistent plane. If one eyewire is twisted forward or backward, making the frame look level from the front can still leave one lens closer to the face or create unequal pantoscopic tilt. Establish the front and hinge alignment before trying to correct vertical height.

02 · BRIDGE CONTACT

Does the bridge contact both sides of the nose evenly?

If one side of the bridge sits deeper or only one edge presses, frame height and centering can change.

The wearer’s nose can also be asymmetric.

Because many plastic bridges have limited adjustment, good bridge-to-nose compatibility matters from frame selection onward.

Because a fixed bridge cannot be moved independently on each side to the same degree as separate nose pads, bridge mismatch limits how much fitting can compensate. Forcing the frame level through temple heat adjustment while one nasal wall bears most of the load can create new pressure or lateral shift. Supplemental pads or limited modification may help in some frames, but a major structural mismatch is usually better addressed with a more suitable bridge shape.

03 · EAR HEIGHT

Different ear heights can affect the frame

A higher ear can make one side of the same temple geometry sit higher or lower.

Front-back ear position can also alter the temple path and the position of the front.

04 · TEMPLE BEND

The two temple bends do not have to be identical

If the ears differ, bend position and curvature can also differ.

A balanced result on the actual face is more important than making both sides look identical on a workbench.

When ear heights differ, the temple bends do not have to be mirror images. The goal is for the front to sit in a comfortable, stable position without a concentrated pressure point behind either ear. When acetate is adjusted, heat only as much of the material as needed and allow it to cool while held in the intended curve so the new shape is stabilized.

05 · ACETATE DEFORMATION

The frame may have changed over time

Heat, repeated handling and poor storage can change acetate shape.

If the frame was fine before and recently began to tilt, inspect both frame deformation and hinge condition.

If a plastic frame fitted well initially but later sits unevenly, separate front distortion, temple distortion, and hinge play. A loose screw or hinge can reproduce the problem even after the acetate has been reshaped. Hardware should be checked and repaired first when necessary, followed by material adjustment rather than using heat to compensate for a mechanical fault.

SOLUTION GUIDE

Solutions at a glance

GLANOS FITTING CHECK

GLANOS fitting check order

1. Front
   Check the frame for twist.
2. Bridge
   Compare left-right nose contact.
3. Width
   Check temple path and side support.
4. Temple bend
   Adjust to the actual ear heights.

CAUTION

Do not force only one temple to make the frame look level

GLANOS EYEWEAR

There is a reason glasses feel uncomfortable.