Hub-centric spacers and bolt-on adapters machined from 6061-T6 on mill-turn centers, held to ±0.005 mm, with 100% inspection before shipment. One prototype or 10,000 parts.
Most spacer complaints trace back to one dimension, one material choice or one unchecked batch.
A lug-centric spacer with a bore 0.15 mm oversize lets the wheel shift on the hub. The driver feels a shimmy through the steering wheel and the studs start to fatigue. Hub-centric fit is not a marketing line. It is the difference between a bore at Ø66.60 mm and one at Ø66.75 mm.
Cheap spacers use low-grade studs with no rolled thread and no hardness check. Torque them to 120 N·m a few times and the thread yields. Buyers then blame the installer. Material certification and a torque test on the finished part remove that argument.
A sharp internal corner between the flange and the hub boss concentrates stress. Extruded 6061 bar with a machined fillet behaves differently from a cast blank with porosity under the skin. When it cracks, it cracks around a lug hole.
The first article fits. The second batch has a different bore, a different face finish or a different anodize shade, and the job stalls at the assembly bench. Without in-process monitoring, the tolerance drifts quietly across the run.
Bolt-on adapters and hub-centric spacers are turning work with a strict perpendicularity callout. We plan the process around that.
Wheel spacers and adapters are round parts with a critical relationship between the wheel face, the hub bore and the bolt circle. We machine them on 16 mill-turn centers so the center bore, the mating face and the stud holes come off the same datum. Turning one face, flipping the part and drilling the pattern in a second setup is where perpendicularity error creeps in.
6061-T6 is our default for spacers and adapters. It machines clean, takes a hardcoat anodize without the surface going chalky, and has enough yield strength for a 10 mm to 40 mm thick part under normal street loads. 7075 is stronger but costs more and anodizes darker in clear. We only push it when a customer is chasing weight or running a track part with 10 mm flange thickness.
For finish, hardcoat anodize gives a wear surface on the wheel face where the rim sits and rubs. Clear anodize is cosmetic. We also run laser marking to a minimum character height of 1.5 mm so the PCD, thickness and batch number stay legible on the flange.
Pick the part type before you pick the material.
| Part type | Typical build | When it is the right call |
|---|---|---|
| Hub-centric spacer | 6 mm to 40 mm thick, bore matched to hub | Wheel already has the correct bolt pattern. You only need offset. |
| Bolt-on adapter | Two bolt patterns, studs pressed in | Moving to a different PCD. Adds thickness from about 15 mm. |
| Slip-on spacer | Flat plate, chamfered bore | Racing use with long studs already fitted. No stud supplier. |
| Custom hub ring | Ø57.1 to Ø72.6 mm, thin wall | Fixing center-bore mismatch between an aftermarket wheel and hub. |
Wheel spacers are one part family. The same shop runs the rest of the car.
Hub-centric and lug-centric spacers, bolt-on adapters, hub rings. 6061-T6 and 7075, with hardcoat anodize and laser-marked PCD.
Camber plates, control arm bushings, subframe inserts, strut mounts. Tight bore tolerances and matched pairs, machined as a set.
Pulley hubs, shifter bushings, differential covers, drive flanges. Stainless and steel options where aluminum is too soft.
Bezel plates, switch panels, pedal covers, gauge pods. Brushed, bead blasted or anodized in colour.
Busbar supports, thermal plates, mounting brackets and enclosures. Aluminum and copper, with conductive anodize where needed.
One-off parts for fit checks before a run. From a single prototype to 10,000+ part runs, no minimum order quantity.
Numbers a purchasing engineer can check against the print.
| Parameter | Capability | Notes |
|---|---|---|
| Tolerance | ±0.005 mm (±0.0002 in) | Bore, face and bolt circle position |
| Surface finish | Ra 0.2–0.8 μm fine | Ra 0.8–1.6 μm on standard faces |
| Maximum part size | 4,000 mm | Larger travel available on request |
| Materials | 6061-T6, 7075, 304, 17-4PH | Titanium and magnesium on request |
| Inspection | 100% before shipment | Reports on request |
| Lead time | Parts ship in 3–5 days | Production can start within 24 hours |
Fifteen years on automotive and industrial parts, across three wholly-owned plants and 7,600 m² of floor space.
Sixteen simultaneous 5-axis centers, twelve four-axis mills and sixteen mill-turn centers. Wheel hardware stays on the mill-turn side.
Send a drawing and we return a quotation with a free DFM analysis within 12 hours. Production can start within 24 hours of approval.
Bore, face and PCD position held to ±0.005 mm, verified with inspection reports on request.
Historical late-delivery probability below 2%. Parts ship in 3–5 days once production starts.
ISO 9001:2015, IATF 16949:2016, ISO 13485:2016 and ISO 27001:2022. Uploads stay confidential; NDA available on request.
Wheel, suspension and battery hardware that has to survive road load and salt spray.
One-off fit checks before a run, then the same process for the production batch.
Mounting brackets and drive components that need matched pairs and flat mating faces.
Aluminum and copper hardware with conductive finishes and tight burr limits.
Hub-centric every time the hub has a register. The bore carries the load and centers the wheel; the studs only clamp. Lug-centric only makes sense on a hub with no register or on a race part where you re-torque often.
To specify it, measure the hub register with a caliper and put that number on the drawing. A 0.05 mm clearance on the bore is workable. A 0.20 mm clearance is a vibration waiting to happen.
We commonly run 6 mm to 40 mm thick spacers and adapters. Above that, weight and stud length become the limiting factors, not the machining.
On bolt-on adapters, the minimum thickness is set by stud head clearance on the back face. Plan on about 15 mm as a practical floor, more if you are pressing in long studs.
6061-T6 handles street use and takes anodize evenly. It is the default for hub-centric spacers, hub rings and most bolt-on adapters.
7075 is worth the extra cost when you are cutting weight or running a thin flange on a track car. It is stronger, but clear anodize comes out darker and hardcoat changes the color more than on 6061.
Ask on the RFQ and we will quote the hardware alongside the machined part. If you supply your own studs, send the knurl diameter and the hole size you want, and we will hold that bore.
We do not guess press-fit diameters. Give us the stud manufacturer's recommended hole size and the interference you want.
The pattern is drilled and reamed in the same setup as the bore, then checked on the CMM against the drawing datum. PCD position and hole diameter are both recorded.
Inspection reports are available on request. We run 100% inspection before shipment, with raw material checks and in-process monitoring through the run.
Yes. Laser marking holds a minimum character height of 1.5 mm, so the PCD, thickness, material and a traceability code stay readable after anodize.
Keep the marking off the sealing face and away from the lug seats. On a thin spacer, tell us the depth limit and we will stay inside it.
A drawing or STEP file with the bore, PCD, thickness, material and finish. If the print is incomplete, we mark it up in the DFM analysis and send it back with the quotation within 12 hours.
Quantities from one piece to 10,000+ are fine. There is no minimum order quantity, and uploads stay confidential under NDA on request.
Yes. The same shop runs suspension plates, bushings, brackets, enclosures and EV hardware in aluminum, stainless, steel, copper and titanium.
If a part needs a second operation like thread milling, bead blasting or anodize, it stays in our process rather than going out to a subcontractor.
Upload your spacer or adapter print and we will return pricing with a free DFM analysis. One part or ten thousand.
12-hour quote100% inspectionNo minimum orderNDA on request
Trusted by engineers and manufacturers worldwide
Upload your 3D model or 2D drawing and get a quotation with a free DFM analysis. Maximum processing size 4,000 mm.
CNC Metals 13 grades
CNC Plastics 10 grades
Machines & processes 12 options
Surface & post-processing 10 options
Material: not selected Machine: not selected Post-process: not selected
Fill in this short form and we'll open WhatsApp with your message ready to send. We only use these details to reply to you.
Nothing is sent until you press send inside WhatsApp.
