Precision couplings
A torque-carrying rotating part: the coaxiality of the two bores matters more than the outside diameter.
Part family · Precision components
Optical light baffles
An optical part: internal matt finish, sharp edges and stray-light control matter more than the outer profile.
What it is, and where it usually goes wrong
A baffle exists to stop light going where it should not. That puts the requirements inside the part: the internal surface must be matt and non-reflective, the aperture edge must be sharp without a burr, and the bore must not have a tool mark that scatters light.
How we machine it
- Cut the aperture with a sharp, freshly honed tool and take a finishing pass measured in hundredths, not tenths.
- Blacken or matt-finish the internal surfaces after machining; a machined aluminium bore will reflect.
- Deburr the aperture edge under magnification — a 20 µm burr is visible in an image and shows as a bright ring.
- Protect the internal finish through packing; a scuff inside a baffle cannot be repaired without re-machining.
Where it is used
Camera and lens modules, optical inspection equipment, sensor windows, laser and imaging systems.
What we check before it ships
- Aperture diameter and edge condition under magnification
- Bore roundness and surface roughness inside the light path
- Concentricity of the aperture to the mounting diameter
- Effectiveness of the matt finish, checked against a sample
Measured against your drawing and written on the inspection sheet that ships with the parts. First article reports are available on request.
What to send for a quote
- Aperture diameter and tolerance, and whether the edge must be knife-sharp
- The wavelength or illumination, since it decides how much scatter is acceptable
- Whether the finish is anodising, black coating or a matt turned surface
- Mounting interface and how the baffle is retained
A STEP file plus a drawing is ideal; a PDF with tolerances also works. Quantity, material and finishing are enough to give you a real price instead of a range.
Questions we get on this part
How do you stop the bore from reflecting?
Two things together: a fine finishing pass so there is no visible tool mark, then a matt black finish — anodised or coated. Machining alone leaves a surface that scatters light even when it looks smooth to the eye.
Can you hold a knife edge on the aperture?
On most metals yes, with a sharp tool and a light final pass, but the edge becomes fragile: it will not survive handling or cleaning by the customer. If the part is handled, tell us and we will quote a small flat instead.
Other precision components we machine
Connecting stems
A slender rod where straightness and the coaxiality of both threaded ends are the two things that decide fit.
Aluminium profile parts
Second-operation work from extrusion or plate, where datum choice and the anodising dimension chain are the risk points.
Send a drawing, get a price within 24 hours
STEP, IGES, DWG, PDF or a dimensioned sketch — plus material, quantity and finishing. We reply with a price and any questions in one message.