Quick answer: Ultrasonic Machining Borofloat 33 covers Borofloat 33 (CTE 3.25 x 10^-6 /K, 350 nm – 2.0 um); Ultrasonic Machining to +/-0.02 mm form. Prototypes ship in 5-10 working days.
Ask any process engineer what makes borofloat 33 difficult and the answer is specific: float tin side must be tracked when parts see coating or bonding steps. Our ultrasonic machining line is tooled around exactly that – 20 kHz ultrasonic spindles with shaped diamond form tools – holding +/-0.02 mm form on parts from 0.5 – 25 mm thick.
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 |
| Process | Ultrasonic Machining |
| Working tolerance | +/-0.02 mm form |
| Minimum feature | 0.3 mm blind features |
| Surface finish | matte machined surface |
| Thickness window | 0.5 – 25 mm |
| Edge condition | crack-free feature edges |
| RFQ inputs | PDF/DXF/STEP drawing, quantity brackets, surface and edge spec |
Manufacturing capability
The core strength of Ultrasonic Machining is blind cavities, non-round holes and stepped profiles that rotary tools cannot reach. The honest limit: material removal is slow, so it is reserved for features other processes cannot form. Both belong on the drawing before quoting, not after.
One material, many routes: on Borofloat 33 we also quote edge grinding, sandblasting, dicing, polishing, and multi-step drawings are the norm rather than the exception.
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.
- Process boundary: material removal is slow, so it is reserved for features other processes cannot form.
- 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.
Who orders this
The recurring buyers of ultrasonic machining borofloat 33: microfluidic devices (chips, manifolds, via plates, bonded stacks); led packaging (groove covers, phosphor carriers, package windows); machine vision (camera windows, ring-light diffusers, calibration plates). 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: wafer dicing process, Borofloat 33 selection guide, microfluidic glass applications.
Buyer questions, answered
What equipment runs the ultrasonic machining work?
20 kHz ultrasonic spindles with shaped diamond form tools.
Is there a minimum order for ultrasonic machining borofloat 33?
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 September 2026.