C90500 Mounting-Flange Bushings for Lathe Tailstock Quills
Request a C90500 mounting-flange guide bushing for a lathe tailstock quill that was designed with a replaceable plain guide. The intended interface is the non-rotating quill’s external sliding surface. This enquiry does not cover the rotating live-centre bearings, spindle bearings or an unsupported conversion of an integral tailstock bore.
Guide the quill without taking over its locking function
Quill guidance has to remain aligned with the machine axis over the useful extension. Provide the tailstock casting section, guide length and any second support. Identify the flange’s locating register and the datums used to establish the guide bore. A bolt pattern alone should not be assumed to maintain centre height or alignment. Report the quill extension at which load and deflection matter most.
C90500 is a tin-bronze material option in BONIU’s directory and should be quoted under its own UNS and product/casting specification. It is not declared equivalent to CuSn12 or another national grade. For this sliding guide, the quill finish, oil supply and installed clearance are central requirements. If an anti-rotation key or slot crosses the guide region, show its geometry and edge relief rather than assuming a plain sleeve can be installed unchanged.
Clamping, chips and thermal conditions affect the fit
Show how the quill lock applies force and whether it can distort the bushing housing. Include machining debris protection, the oil-feed connection and the temperatures at which alignment and clearance are inspected. The guide sleeve cannot correct bed wear, tailstock misalignment or a damaged quill surface. If the original bore is integral to the casting, a replaceable flange insert needs machine-design approval before a manufacturing quotation is finalized.
Drawing and quotation checklist
Send a dimensioned new-part drawing with units and revision, the mating assembly and the following application details.
| Review item | Information to provide |
|---|---|
| Guide dimensions | Quill diameter/finish, bore, body OD/length, flange dimensions and sliding clearance. |
| Location and alignment | Register fit, hole pattern, mounting-face datum, bore axis and relation to machine centre height. |
| Functional details | Oil passage, groove requirements, anti-rotation feature, quill lock and travel stops. |
| Service and inspection | Maximum working extension, lateral/axial reactions, housing stiffness and inspection temperature. |
| Material and purchase | C90500 with casting/product standard, quantity, drawing revision and alignment/fit acceptance criteria. |
Installation and selection checks
Inspect the quill surface and housing locating features before fitting the guide. Seat the flange evenly and establish bore alignment using the machine’s approved procedure. Verify sliding clearance throughout travel with the lock released, then check the locking function and oil feed. Confirm that keys, grooves and stops do not scrape the bearing edge. Perform final alignment checks before returning the machine to cutting work.
Frequently asked questions
Is this a replacement for the live centre’s rolling bearings?
No. It guides the outside of the translating quill. Live-centre bearing selection is a separate rotating-bearing requirement.
Can the flange bolts be used to pull a misaligned guide into place?
The mounting face and locating features should establish the correct position. Bolt force should not be used to distort the guide to compensate for incorrect geometry.
What if the tailstock never had a removable bushing?
Provide the casting and repair proposal for engineering review first. A new insert changes wall thickness, support and alignment requirements and is not a like-for-like sleeve replacement.
Request a drawing-based quotation
Send the drawing, C90500 tin bronze specification, quantity and operating details through Contact BONIU. Include any required material documentation and inspection criteria. Material route, manufacturing feasibility and delivery are confirmed in the quotation.