Injection Molding
Tooling and molding for your repeat plastic parts.
YOUR CONTACT FACES. YOUR APPEARANCE. YOUR FINISHED FIT.
Surface Finish Selection Connect Your Finish to the Function of Your Part
For surface finish selection for machined parts, start with the substrate, working environment, mating features and visible surfaces. Agree what is measured and what is judged visually before release.
Separate the Finish Requirement from the Finish Name
Corrosion & environment
Identify substrate, exposure, cleaning and the applicable test or acceptance specification. A finish name alone does not establish service life.
Contact & assembly
Mark mating fits, threads, electrical contacts and sealing faces that need protection or post-finish inspection.
Appearance
Define visible zones, color or texture references, permissible marks and an agreed viewing condition.
Define Your Dimensions in the Finished Condition
For anodizing dimensional allowance, distinguish the specified coating thickness from the change in the outside dimension. Do not apply the deposited-layer example below to anodizing without process-specific review.
Illustrative two-face gap reduction
Assume a uniform deposited layer t on each of two opposing flat faces. Gap reduction = 2t. Zero baseline0–30μm.
Assumed geometry only. These are not prescribed coating thicknesses, measured results or an anodizing growth model. Real growth, distribution and substrate removal depend on the specified process.
A matching appearance does not prove a matching fit. Background on finish-related dimensions: Protocase finish tolerance guidance →. Its supplier-specific values are not LK MFG specifications.
Show the Surfaces That Must Stay Different
Mark masked zones and the required condition after finishing. Review practical boundaries and inspection access rather than relying on a color rendering.
Electrical contacts
Identify contact pads, bonding areas and the required surface condition.
Fits & threads
Show which bores, seats or threads require protection or a controlled finished dimension.
Edges & transitions
Agree mask boundary locations, handling marks and appearance expectations near transitions.
Background: Protolabs finishing and masking overview →. The photograph is an illustrative concept,not evidence of a measured coating.
Keep Roughness and Cosmetic Approval as Separate Checks
Drawing requirement
Surface roughness requirements on drawings should identify the controlled surface,parameter,units and applicable measurement conditions.
Visual requirement
Cosmetic surface acceptance criteria should identify visible zones,reference samples,lighting,viewing condition and permissible marks.
Approval evidence
Agree which records support dimensional,coating and appearance acceptance. A glossy photograph is not a roughness report.
No numerical roughness value is assigned to either concept surface.
Review Your 3D Printed Surface Finish by Process and Material
A 3D printed surface finish depends on build process,material,orientation,support contacts and the selected post-processing route. Agree how finishing affects details and mating features.
Layer & support marks
Identify surfaces where texture or support removal matters to function or appearance.
Post-processing scope
Review cleaning,sanding,blasting,painting or another proposed route for your actual material. Availability is confirmed by project.
Finished dimensions
Define any critical surfaces that require measurement after finishing rather than judging fit from appearance.
The two components are different illustrative concepts,not a before-and-after test. Reference topics: Xometry process-specific finish options →.
6 Inputs for Your Finish Review
- Material grade,condition and manufacturing process.
- Finish specification and required final condition.
- Critical dimensions and after-finish measurement needs.
- Masked zones,contacts,threads and sealing faces.
- Appearance reference and visible surface zones.
- Quantity,required records and approval responsibilities.
Answers Before You Specify the Finish
Should dimensions be specified before or after plating?
State the required acceptance condition explicitly. Identify finished fits,threads,masked areas and any dimensions that must also be controlled before treatment.
Can I use coating thickness as anodizing outward growth?
Do not assume they are identical. Review the alloy,pretreatment,anodizing specification and dimensional change with the finishing supplier.
Does a polished appearance establish a roughness value?
No. Specify the surface parameter and measurement conditions. Judge cosmetic requirements against a separately agreed visual standard.
Can every finish be applied to every material?
No. Confirm substrate compatibility,process availability,functional requirements and final acceptance before ordering.
Review finishing services → · Connect finish to inspection → · Review part design →
