Borofloat 33 Glass Covers – Borofloat 33 (CTE 3.25 x 10^-6 /K, 350 nm – 2.0 um); 0.1 – 3 mm thick, contours to drawing. No minimum order; DFM review included with every RFQ.
A drawing for borofloat 33 glass covers is mostly a conversation about edges and datums. We produce them in Borofloat 33 at 0.1 – 3 mm thick, contours to drawing, with outline +/-0.05 mm as the controlling tolerance, and finish the perimeter per spec.
Specification envelope
| Material | Borofloat 33 (SCHOTT float production, wafer grade) |
|---|---|
| Thermal expansion (CTE) | 3.25 x 10^-6 /K |
| Service temperature | 450 C continuous |
| Transmission range | 350 nm – 2.0 um |
| Density | 2.23 g/cm3 |
| Knoop hardness | 480 kg/mm2 |
| Refractive index | 1.471 @ 587 nm |
| Stock thickness | 0.70 – 25.4 mm |
| Maximum blank size | 500 x 500 mm |
| Geometry | Glass Covers |
| Size envelope | 0.1 – 3 mm thick, contours to drawing |
| Key tolerance | outline +/-0.05 mm |
| RFQ inputs | PDF/DXF/STEP drawing, quantity brackets, surface and edge spec |
Capabilities and limits
One material, many routes: on Borofloat 33 we also quote ultrasonic machining, sandblasting, dicing, double-side polishing, and multi-step drawings are the norm rather than the exception.
Production route: laser cutting, cnc machining, edge grinding – selected per geometry and volume. Edge condition: filamentation edge, optional post-polish.
Specification advice
Before sending the RFQ, check these against your drawing:
- Material note: float tin side must be tracked when parts see coating or bonding steps.
- Hold the controlling dimension (outline +/-0.05 mm) and let secondary dimensions carry standard tolerance – it is the single biggest cost lever.
- Over-specification is the quiet budget killer: a 20/10 scratch-dig face costs roughly three times an 80/50 face, so grade each surface individually.
For the complete framework, see the tolerance design guide and the holes and edges design guide.
Application context
borofloat 33 glass covers shows up across optical sensors (sensor windows, filter caps, lens covers); machine vision (camera windows, ring-light diffusers, calibration plates); mems devices (cap wafers, TGV substrates, motion-sensor lids). Background reading on the underlying material science: SCHOTT BOROFLOAT product page.
Dimensions still moving? Configure this part live in the 3D + 2D builder below, or open the full custom glass machining 3D + 2D builder to start from a blank canvas.
For adjacent specifications, see surface quality guide, material selection guide, glass wafer bonding.
Common questions
How does Borofloat 33 behave under heat?
CTE is 3.25 x 10^-6 /K and continuous service reaches 450 C continuous, which is what drives its use where float-glass flatness off the line matters.
What sizes are available for glass covers?
0.1 – 3 mm thick, contours to drawing, held to outline +/-0.05 mm.
Is there a minimum order for borofloat 33 glass covers?
No. Single prototypes are accepted, and pricing steps down at 10, 100 and 1,000 pieces.
How fast can prototypes ship?
Machined prototypes ship in 5 – 10 working days. Coated or bonded parts add 1 – 2 weeks depending on queue slots.
What files do you need for a quote?
A dimensioned PDF plus DXF or STEP geometry. If only a sketch exists, our drawing review service formalizes it before quoting.
Specifications on this page were last reviewed by our engineering team in August 2026.