Ask an Engineer: 262-377-2434
Not a general job shop. A tight-tolerance shop with deep process capability in turned and ground rotational components: shafts, cylinders, bores, and complex assemblies.
Where most shops stop at turning, we hold the finished outside diameter to spec.
Send a pre-turned, heat-treated blank for final grinding, or hand off the full sequence start to finish.
Holding geometry and finish inside a bore takes the right equipment and the right discipline.
Thread rolling produces stronger threads than cutting by working the material, not removing it. It runs integrated with turning and grinding under the same roof. Also available: precision flat surface grinding, 5-axis CNC, way grinding up to 26 feet, and horizontal/vertical machining. A trusted partner network handles heat treat, plating, and other outside processing.
The standard path for a complex precision shaft: buy material, send to a shop for rough turning, ship to heat treat, ship to a grinder, ship back for thread rolling. Four vendors. Four handoffs. Four lead times stacked. Four chances for tolerances to stack up in the final part.
Turnkey changes that math. Turning, OD grinding, and thread rolling run in sequence under one roof. No inter-vendor logistics. No dimensional variation introduced at every handoff.
One vendor. One quality system. One lead time. That's what turnkey actually means.
The proof: A customer was issuing four separate POs to complete a single shaft. We furnished the material, did the turning, coordinated heat treat, and finished the OD grinding and thread rolling in-house. Same spec. Fewer variables. Shorter lead time. Less PO tracking, less driver time, more focus on their core business.
| Shop Type | Where They Break Down | Where We Fit |
|---|---|---|
| Production volume shop | Won't quote 25–50 pieces at tight tolerance |
setup cost kills the margin 25–50 pieces is our sweet spot |
| General job shop | Can turn a part but lacks grinding depth for final tolerance |
Turning and grinding in-house, no handoff |
| Prototype shop | Inconsistent piece to piece; no lot-level documentation Every piece inspected; |
documentation standard |
| Single-process specialists | Grinder can't turn; turner doesn't grind Full process |
turner doesn't grind Full process, raw material to finished part |
Production shops are built for volume. 25 pieces disrupts their setups and erodes margins, so they price it to refuse. Prototype shops can handle small quantities but rarely the tolerances. We run the same processes for a 25-piece job that we use for our own spindle components. Setups are meticulous. Inspection is documented. Parts ship to print.
Work centers on rotational and cylindrical components where OD/ID grinding, tight runout, and multi-step processing are required.
The core of our contract machining work. Shafts for thread rolling machines, gearboxes, and industrial equipment where diameter tolerances, runout, and surface finish are demanding. Common scope: rough turning, heat treat coordination, and final OD grinding under one program.
Camshaft grinding requires precision lobe geometry, controlled surface finish, and tight runout across a complex profile. When micrometer-level tolerances and a turnkey solution are needed, we produce blank or fully manufactured camshafts in-house.
A long history producing shafts, housings, and centrifuge assemblies, primarily for blood and plasma collection. These assemblies operate at lower ambient temperatures to prevent specimen spoilage, which depends on precision-manufactured housings and shafts. Also: imaging equipment rotating assemblies, X-ray tube components, and other medical applications requiring material traceability, controlled surface finish, and lot-level inspection.
ID grinding for bearing fits, shaft fits, and functional interfaces in precision assemblies.
The customers who find us have usually exhausted their supplier list. They need process depth and a shop willing to commit to tight tolerances at low volume. Conversations typically start with: "Here's our print. Can you make this?"
When part quality, repeatability, and documentation matter, Gilman provides the machining expertise to get it right the first time.
What types of parts does Gilman precision contract machining cover?
Gilman's contract machining capability is focused on precision rotational components: shafts, cylinders, bores, and complex turned and ground assemblies. The work centers on parts requiring OD grinding, ID grinding, or precision turning to tight dimensional tolerances. Representative examples include precision shafts for thread rolling and gearbox applications, camshaft grinding, medical rotating assemblies, and precision bores for bearing and spindle fits. In select cases, Gilman will also open up our surface grinding, mill/turn, and 5-axis CNC production capacity when appropriate.
What is the minimum and maximum quantity Gilman will run for contract machining?
Gilman's contract machining sweet spot is low-volume, high-complexity work in the range of 25 to 50 pieces per run, though we are of course open to larger volumes. This is the quantity range that production shops typically won't price competitively and that prototype shops often can't hold to specification consistently. Minimum and maximum quantities depend on the specific part and process requirements. Contact Gilman to discuss your quantity and part requirements directly.
What tolerances can Gilman hold on OD ground shafts?
'Gilman holds OD tolerances to [+/- 0001 inches] on ground shafts, with runout to [X microns / X ten-thousandths] depending on diameter and material. Specific tolerance targets should be discussed with Gilman's engineering team for your application.']
Can Gilman manage the full machining sequence from raw material to finished part?
Yes. Gilman's turnkey contract machining capability covers the full process sequence for precision shafts and rotational components: rough turning, OD and ID grinding, thread rolling where required, and process coordination for heat treatment and/or plating. Customers can furnish raw material or have Gilman procure it. The advantage of turnkey processing at Gilman is that each step in the sequence happens under one quality system, without the dimensional variation and scheduling delays that occur when multiple vendors handle the same part.
Does Gilman provide inspection documentation and material traceability for contract machined parts?
Yes. Gilman provides dimensional inspection records and material certifications. For customers in regulated industries such as medical device manufacturing or aerospace, Gilman's ISO 9001:2015 certified quality system provides the documentation framework needed for supplier qualification and lot traceability.
How is Gilman's contract machining capability related to its spindle manufacturing?
Gilman's contract machining capability emerged directly from the same processes used to manufacture its own spindle components. Spindle manufacturing requires extremely tight tolerances on turned and ground components: journals, bores, and cylindrical surfaces held to precision fits. The equipment, tooling, and process discipline built for spindle production is exactly what Gilman applies to contract machining work. The result is a contract machining operation with significantly more process depth than a general job shop, because it was built to meet the demands of precision spindle manufacturing.
How do I submit a drawing for a quote?
Submit your drawing and quantity requirements through the Technical RFQ form at gilmanprecision.com/get-a-quote, or call Gilman directly at 262-377-2434 and ask for the applications engineering team. Gilman's engineers will review the drawing, identify any questions about tolerances or process requirements, and provide a quote with lead time. The more detail on the drawing, the faster the quoting process.
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If your drawing has tolerances that are making other shops hesitate, send it to Gilman. The engineers who review it understand tight-tolerance rotational components. The quote will reflect what the part actually requires.
Submit a Technical RFQ: Share your drawing, material, and quantity at gilmanprecision.com/get-a-quote. Include any notes on critical tolerances or inspection requirements.
Call the Shop: 262-377-2434. Ask for applications engineering. If it is a precision shaft, bore, or rotational component in a small quantity, the conversation will be direct and technical.
+ Submit a Drawing + Call 262-377-2434
Built in Wisconsin. Machined to the tolerances other shops won't commit to. Gilman Precision, since 1951.
If your drawing has tolerances that are making other shops hesitate, send it to Gilman. The engineers who review it understand tight-tolerance rotational components. The quote will reflect what the part actually requires.
Submit a Technical RFQ: Share your drawing, material, and quantity at gilmanprecision.com/get-a-quote. Include any notes on critical tolerances or inspection requirements.
Call the Shop: 262-377-2434. Ask for applications engineering. If it is a precision shaft, bore, or rotational component in a small quantity, the conversation will be direct and technical.
+ Submit a Drawing + Call 262-377-2434
Built in Wisconsin. Machined to the tolerances other shops won't commit to. Gilman Precision, since 1951.
