Capabilities
BELL Machine Works runs 5-axis CNC machining for parts that have to be right the first time, with a particular strength in the engineering plastics most shops would rather not quote. Below is what we hold, what we cut, how we finish it, and how fast it ships.
| Specification | Value |
|---|---|
| Standard tolerance | ±0.001" |
| Tightest held, where the part calls for it | ±0.0002" |
| Surface finish, measured on engineering plastics | 32 μin Ra |
| Surface finish, measured on aluminum | 16 μin Ra |
| Typical drawing callout we quote to | 125 μin Ra |
| Minimum feature size | Ø0.010" |
| Depth-to-diameter ratio | up to 8:1 |
| Work envelope, 5-axis | 8" × 8" × 3" |
| Spindle speed | 45,000 RPM |
| Standard lead time | 2 weeks |
| Rush lead time | 24 hours |
| Minimum order quantity | None. 1 to 1,000+ |
Work envelope
What fits
5-axis simultaneous, 8 × 8 × 3 inches. Drawn to scale on a one-inch grid so you can check your part against it at a glance.
Does your part fit? Checked in every orientation
Where we are strongest
Engineering plastics
PTFE, Delrin, polycarbonate and UHMW are soft, they move with temperature, and they tear rather than shear the moment a tool is past its best. Everything that makes them useful makes them hard to hold a dimension in, which is why most shops would rather not quote them, and why we run them more than anything else.
We finish these materials straight off the machine, with no secondary operation. A machined surface is commonly called out at 125 μin Ra; we measure 32 on a profilometer.
Materials
Titanium & nickel
- Titanium Grade 5
- Inconel 625
- Inconel 718
Stainless steels
- 303
- 304
- 316 / 316L
- 17-4 PH
- 15-5 PH
Non-ferrous alloys
- Aluminum 6061
- Aluminum 7075
- Copper
- Brass
- Bronze
Plastics
- PTFE
- Delrin
- Polycarbonate
- UHMW
- PEEK
- Ultem
- Torlon
- Vespel
Working in something not on this list? Send the drawing. Most of what we run started as a one-off request.
Finishes and marking
Anodize Type I/II/III per MIL-A-8625, chem film per MIL-DTL-5541, passivation and electropolish per AMS 2700 / ASTM A967 / ASTM B912, plating in electroless nickel, nickel sulfamate, gold, silver, copper and tin, blast and prep, and MIL-STD-130 laser engraving. All plating and anodize run through an ITAR-registered finishing house, certs returning with the parts.
Part type · material · finish · tolerance only
Representative parts
- Tube raceway clamps in PTFE for cryogenic propellant lines
- Microfluidic manifold halves in clear polycarbonate, 0.4 mm channels
- Thin-wall guide plates in Delrin, our tightest documented tolerance
- Flow distribution plates in Delrin
- Optical transition and backing blocks in aluminum, ten tight-tolerance locations
- Assembly and trim fixtures in Delrin, acetal and stainless
- Cable clamps and cable saddles in polycarbonate and Delrin
- O-ring sealed brackets and plates in aluminum for vacuum and gas service
- Micro-D connector covers in aluminum, electroless nickel plated, laser engraved per MIL-STD-130
- Thermal management baseplates in copper
- Threaded pressure-hull penetrators in stainless
- Wear blocks and guides in UHMW and bronze
Inspection
Measurement and documentation
In-house CMM with digital GD&T verification, surface finish measured on a profilometer, in-process checks on every digital traveler, and first article inspection on request. Every order ships with material certs, lot traceability and a Certificate of Conformance; mill certs go out with the parts.
Inspection & traceability in depth →
CAD formats accepted
- STEP
- IGES
- Parasolid
- STL
- DWG
- DXF
Lead times
Standard: two weeks. Quoted, scheduled, inspected, shipped.
Rush: 24 hours. Available on request. Same tolerances, same inspection, same documentation. The only thing that changes is where your job sits in the queue.
Revisions don't restart the clock. Digital travelers and revision control in ProShop ERP mean a drawing change is a controlled update to a live job, not a new job.
Quality and compliance
- ITAR registered · CAGE 18MB0. Registered with the U.S. Department of State, Directorate of Defense Trade Controls.
- Technical data on Microsoft GCC High. A separate, isolated tenant on U.S. soil under U.S.-person administration. Infrastructure, not a certification.
- ISO 9001 and AS9100D compliant. Third-party certification audits scheduled for Q1 2027.