Borofloat 33 Glass With Internal Cutouts – Borofloat 33 (CTE 3.25 x 10^-6 /K, 350 nm – 2.0 um); Internal windows with R0.5 mm minimum corner. No minimum order; DFM review included with every RFQ.
A drawing for borofloat 33 glass with internal cutouts is mostly a conversation about edges and datums. We produce them in Borofloat 33 at Internal windows with R0.5 mm minimum corner, with cutout +/-0.05 mm as the controlling tolerance, and finish the perimeter per spec.
The numbers
| 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 With Internal Cutouts |
| Size envelope | Internal windows with R0.5 mm minimum corner |
| Key tolerance | cutout +/-0.05 mm |
| RFQ inputs | PDF/DXF/STEP drawing, quantity brackets, surface and edge spec |
Getting the drawing right
Three items decide most of the cost and lead time on this work:
- Material note: float tin side must be tracked when parts see coating or bonding steps.
- Hold the controlling dimension (cutout +/-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.
Manufacturing capability
One material, many routes: on Borofloat 33 we also quote edge grinding, lapping, sandblasting, cnc machining, and multi-step drawings are the norm rather than the exception.
Production route: cnc machining, laser cutting, ultrasonic machining – selected per geometry and volume. Edge condition: chamfered 0.1 – 0.5 mm as standard.
Typical applications
borofloat 33 glass with internal cutouts shows up across mems devices (cap wafers, TGV substrates, motion-sensor lids); microfluidic devices (chips, manifolds, via plates, bonded stacks); led packaging (groove covers, phosphor carriers, package windows). Background reading on the underlying material science: SCHOTT BOROFLOAT product page.
The fastest route to a quote is geometry: use the 3D builder below, draw a dimensioned 2D drawing from it, or open the site-wide custom glass machining 3D + 2D builder for fully custom parts.
Related reading on this site: microfluidic glass applications, alkali-free display glass, alkali-free glass wafers.
Frequently asked questions
Is there a minimum order for borofloat 33 glass with internal cutouts?
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.
Do parts ship with inspection data?
Dimensional reports, surface certificates and material certs per melt are available; specify the level on the RFQ.
What tolerances are achievable on Borofloat 33 parts?
Ground features hold +/-0.01 mm and lapped thickness reaches +/-0.003 mm. Float tin side must be tracked when parts see coating or bonding steps.
Specifications on this page were last reviewed by our engineering team in September 2026.