A full-rim frame surrounds the lens edge with an eyewire. Semi-rimless and rimless designs use less frame material, so the finished lens edge must do more mechanical work.
That changes the importance of groove or drill geometry, lens material, local thickness and final assembly.
01 · FULL RIM
The eyewire supports the lens around its perimeter
A full-rim lens is commonly edged with a bevel that seats in the frame groove. The eyewire distributes retention around much of the lens edge.
Material and thickness still matter, but the lens itself carries less of the frame structure than in a rimless design.
02 · SEMI-RIMLESS
A groove holds the nylon cord
A narrow groove is cut around the exposed lens edge so the cord can retain the lens. Groove depth and position must match the local edge thickness and the cord system.
If the groove is too close to one surface or the edge is too thin, retention and edge durability can suffer. The thinnest part of the shape should be checked before choosing the design.
03 · RIMLESS
Hardware loads the lens directly
Rimless frames use drilled holes or slots so bridge and temple hardware connect to the lens. These areas experience concentrated mechanical stress during wear.
Hole position, distance from the edge, drilling angle and the screw/bushing system must work together. Over-tightening can concentrate stress; under-tightening can allow movement.
04 · MATERIAL
Mechanical behavior matters more
Because exposed edges and drill sites carry more load, material selection should consider impact behavior, crack resistance and machining characteristics as well as refractive index.
A material being relatively impact resistant does not mean the finished rimless pair automatically meets any sports or protective-eyewear standard.
05 · LOCAL THICKNESS
Check thickness where the hardware actually sits
Plus powers and complex prescriptions can create different thicknesses at the right and left drill sites. The planned holes or grooves need enough local material for the chosen hardware.
“Thinner looks better” is not a safe rule if it leaves the groove or drill area mechanically weak.
06 · FINAL ASSEMBLY
Finishing and rechecking are part of the structure
After assembly, check that the lenses are not twisted, hardware is not over-compressed, and a semi-rimless cord has even retention.
Exposed edges also need appropriate safety beveling and clean finishing because they directly affect appearance and handling.
SOLUTION GUIDE
How the frame type changes edging
Bevel into the eyewire groove.
Groove for the retaining cord.
Drill or slot for hardware.
Consider machining and mechanical behavior.
Verify the groove or drill area before cutting.
GLANOS LENS CHECK
In rimless eyewear, the lens itself becomes part of the frame structure.
Optics, local thickness, material and hardware must be designed together.
CAUTION
Do not assume that an impact-resistant lens material is automatically suitable for every rimless construction.
Do not assume that an impact-resistant lens material is automatically suitable for every rimless construction.
GLANOS EYEWEAR
Eyewear discomfort has a reason.
rimless glasses, semi-rimless, lens edging, drilling, grooving, nylon cord