Get quotes for custom turned parts
Round, cylindrical, and shaft-like parts turned from bar stock on CNC lathes, with live tooling and Swiss options for the tricky ones. Upload your drawing and we'll source competitive quotes from qualified manufacturing partners.
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Uploads are secure & confidential
How OpenSpindle works
We tap our partner network. You get the best-match quote.
Upload your part and we tap our network of partner shops to get you a competitive, all-in quote that is the best match for the job.
One upload
A CAD file or a sketch. That is the whole ask on your end.
Your best-match quote
Sourced from the partner shops set up for your exact part.
All-in, on your timeline
Machining, finishing, and shipping detailed to your turnaround.
Bar stock our turning shops run
Turning starts from round bar. Common alloys are below; if yours is not here, ask when you request a quote.
Specs
Tolerances you can expect
| Feature | With a drawing | No drawing supplied |
|---|---|---|
| Turned diameter | ±0.002 in | ISO 2768 Medium |
| Length | ±0.005 in | ISO 2768 Medium |
| Bore diameter (not reamed) | ±0.003 in | ISO 2768 Medium |
| Surface finish | 63-125 Ra | 125 Ra as-turned |
Diameters hold tighter than lengths on a lathe. Reamed and ground bores go tighter; call those out on your drawing and shops confirm before turning.
Design rules
How to design for CNC Turning
The design choices that most affect whether a turned part runs fast and clean on a lathe.
| Design rule | Typical spec | Why |
|---|---|---|
| Max length-to-diameter (unsupported) | <= 3x | Longer slender parts deflect and chatter; a steady rest extends this. |
| Min bore diameter | >= 0.040 in (1 mm) | Small bores need long, fragile boring bars. |
| Min groove / undercut width | >= tool width (~0.030 in) | The grooving tool needs room to enter the cut. |
| Min wall on turned tubes | >= 0.020 in | Thin walls flex and chatter under the tool. |
| Tapped thread depth | 1.5 to 2x diameter | Deeper threads add cost without adding strength. |
| Standard tolerance | +/- 0.005 in | Tighter on diameters with grinding or live tooling. |
Typical starting points; a shop confirms against your drawing and material.
Reference
Related reference charts
Free spec + tolerance charts for designing these parts.
Secondary operations
Inserts, hardware and finishing
Threads and inserts
Single-point and die-cut threads, cross-drilled and tapped holes, knurls, and pressed inserts done in the same setup or as a secondary op.
Finishing
Applied after turning. As-turned ships fastest; passivation, anodize, and plating are common on turned metal parts.
| Finish | Materials | Adds | Can be applied with |
|---|---|---|---|
| As-turned | All | +0 days | Anything |
| Passivation | Stainless only | +2 days | Bead blast |
| Anodize | Aluminum, titanium | +3-5 days | Bead blast |
| Zinc / nickel plating | Steel | +3-5 days | Passivation not needed |
Threads made before plating can go out of spec after the coating adds thickness. Tell the shop so they cut for the final size.
Process comparison
CNC turning vs other processes
When another process fits better than turning a part on a lathe.
| Process | Best for | Typical volume | Choose it over CNC Turning when |
|---|---|---|---|
| CNC Machining (Milling) | Prismatic parts with pockets and faces | Prototype to production | The part is not round and needs milled features. |
| Swiss Machining | Small-diameter high-volume precision parts | High volume | Parts are small, long, and needed in the thousands to tight tolerance. |
| 3D Printing | Complex non-round geometry | One-off to low volume | The shape cannot be turned on a lathe. |
Get a better quote
Getting a quote that comes back fast
| Instead of | Send this |
|---|---|
| "Turned part, need a quote" | "303 stainless shaft, ⌀0.500 x 3.0 in, ±0.002 on the OD, qty 100" |
| "Threaded on one end" | "1/4-20 UNC x 0.50 deep, tapped, one end per drawing" |
| "Smooth finish" | "63 Ra on the bearing journal, as-turned elsewhere" |
Say which diameter is critical and where it mates. That is what sets the tolerance and the price.
Applications
Industries we serve
Turning shops on OpenSpindle produce shafts, pins, fittings, and fasteners for demanding industries, including AS9100 and ITAR-registered shops.
More on OpenSpindle
Need a different process?
Get a quote for these capabilities too.
Designing for this process
What actually changes your quote
Not a definition of turning. The design choices that move your price and lead time.
Length-to-diameter drives cost
Long, slender parts (past about 8x diameter) deflect and chatter, needing steady rests or slower feeds. Keep parts stubby where you can.
One critical diameter, not five
Every tight OD needs its own inspection pass. Tolerance the one that mates a bearing or bore and leave the rest as-turned.
Undercuts need clearance
A tool has to reach the groove. Add a relief or a tool-clearance radius at shoulders so the shop is not forced into a special tool.
Deep bores get expensive
Boring past about 3x the bore diameter needs a longer, floppier bar and slower cuts. Through-holes and shallow bores turn cheaper.
Questions
Frequently asked questions
Turning spins the part against a fixed tool to make round features like shafts, pins, and bushings. Milling holds the part still and spins the tool to make prismatic features. Many shops do both and pick the right one from your drawing.
Get CNC turning quotes
Upload your drawing and we'll source competitive quotes from qualified manufacturing partners.
STEP · STL · IGES · DWG · DXF · PDF · and more
Uploads are secure & confidential