Drawing-Based Custom Manufacturing
Mechanical Assembly for Custom Parts & Subassemblies
Mechanical assembly combines custom components and specified hardware into a usable subassembly. Typical projects include aluminum profile frames, machined housings with covers, and mixed metal-plastic mechanisms. JUNCHU coordinates the bill of materials, part revisions, fastening sequence and agreed fit checks so the delivered scope is clear.
Hardware · Subassemblies
Frames · Housings
PART TYPES
Metal & Plastic Parts
Specified Hardware
MATERIAL ROUTES
Fasteners · Hardware
Checks · Identification
ASSEMBLY SCOPE
BOM · Revisions
Fit Checks
ASSEMBLY INPUTS
Mechanical Assembly Applications
From separate parts to a defined subassembly
Successful assembly starts before parts are made. Mating tolerances, coatings and tool access can determine whether otherwise acceptable components fit together.
Define each component, revision and purchased item in the bill of materials. Confirm who supplies each item and identify interfaces that control assembly fit.
Before Manufacturing
Define Your Project Requirements
The quotation confirms the drawing requirements, manufacturing scope, inspection and schedule for your specific parts.
01
Assembly Acceptance
Define fit, alignment, fastening and any agreed functional checks.
02
BOM & Revision Control
Provide an itemized bill of materials and the approved component revisions.
03
Production Schedule
Confirmed after reviewing tooling, purchased items, quantity and finish.
04
Size & Handling
Share overall dimensions and weight so workholding, processing and packing can be reviewed.
Assembly Interfaces & Hardware
Control how the components work together
Connection Feature
Assembly Requirement
Threads & Screws
Thread standard, engagement, screw length and tool access
Inserts & Studs
Base material, installation method and retention requirement
Locking Method
Specified torque, locking feature or approved adhesive
Fastener selection must suit the joint, component material and service conditions.
Start Your Mechanical Assembly Project
Define what makes a complete assembly: the released BOM, component revisions, joining instructions, acceptance checks and delivery configuration.
Review the BOM
Share component drawings, BOM quantities, revision levels and hardware specifications. Identify customer-supplied items and requested assembly quantities.
Build & Confirm
Agree the assembly sequence, joint requirements and first-assembly approval before repeating the build across the batch.
Verify the Assembly
Check component count, orientation, fit and specified joint requirements. Agree any movement checks, fixtures and records before work starts.
Identify & Pack
Confirm labels, matched sets, loose hardware and the shipping configuration so each delivery contains the intended assembly or kit.
Typical Mechanical Subassemblies
Components combined around a clear function
These are examples of assembly configurations. The quotation defines the components, purchased items and checks included in your project.
01
Profile Frames
Cut and machined extrusions joined with brackets and fasteners; check squareness and the location of mounting interfaces.
02
Housing Assemblies
Machined or extruded bodies fitted with covers, end plates and hardware; inspect final fit and cosmetic alignment.
03
Tube Mechanisms
Mating tubes combined with bushes, stops or clamps; review sliding clearance and retention after surface treatment.
04
Equipment Mounts
Brackets, plates and spacers supplied as a subassembly; define locating datums, orientation and fastener access.
05
Mixed Metal-Plastic Parts
Metal bodies paired with polymer guides, caps or wear components; account for moisture and thermal movement.
06
Hardware Kits
Matched parts and specified hardware packed for the next assembly stage; identify item numbers, quantities and installation information.
Project Planning
Planning an Assembly Order
Define the supplied components, acceptance checks and delivery configuration before work is scheduled.
Assembly or a Matched Parts Kit
A completed subassembly can reduce receiving and fitting work, while a labeled kit may suit installation at the destination. Compare overall size, handling risk, access for final installation and shipping cost. Clearly identify which joints are completed and which are left for the receiving team.
What Drives Assembly Cost
BOM size, part availability, fastening steps, fixture needs and agreed checking procedures affect effort. Adhesive cure time, special torque requirements and repeated adjustment can also affect scheduling. Separate purchased hardware, custom component manufacture, assembly labor and any separately agreed testing in the quotation.
Approve the First Assembly
Use the approved component revisions and intended surface finishes for trial fitting. Check alignment, travel, retention and tool access against the agreed acceptance criteria. Record any approved shims, adjustments or work instructions so repeat assemblies follow a defined configuration rather than an undocumented sample.
Pack for the Next Operation
Specify whether delivery is assembled, partly assembled or packed as matched sets. Identify loose hardware, orientation, lifting or support needs and items that must remain protected. Functional, electrical, sealing or load tests require an agreed procedure and acceptance criteria; mechanical assembly alone does not imply these tests.
Component images are 3D concept illustrations of representative parts.
Before You Start Your Project
Common Questions
Before an RFQ
Review the information needed for a clear quotation, practical process planning and agreed inspection requirements.
What is needed to quote an assembly?
Provide an assembly drawing, bill of materials, component revisions, quantity and any assembly instructions. Identify supplied parts, purchased hardware, critical interfaces and the checks required before packing.
Can supplied components be included?
Specify which items you will supply, their condition, quantities and expected arrival dates. Incoming acceptance, shortages, replacements and ownership of purchased items should be agreed before scheduling assembly.
How are fit and fastening requirements controlled?
State mating fits, alignment, torque, locking method and any adhesive or curing requirement. Review the finished condition of coated components and identify the features that need trial fitting.
Does assembly include electrical or performance testing?
The quotation defines the work included. Mechanical fit checks differ from electrical, load, sealing or product-compliance tests. Any functional test needs an agreed method, acceptance criteria and required records.
What defines the delivered assembly configuration?
Use an approved BOM and component revisions to identify the assembly, supplied hardware and any loose items. Record orientation, fastening or locking requirements and the agreed fit checks. State whether shipment is fully assembled, partly assembled or packed as matched sets. Separately agreed functional tests and their acceptance criteria should be identified in the delivery scope.
Use the BOM to Define the Complete Assembly Scope
| Assembly input | What to agree | Acceptance consideration |
|---|---|---|
| Custom and purchased items | Component revisions, hardware specifications and supplied items | Record approved equivalents and identify substitutions. |
| Mechanical interfaces | Datums, fits, travel, torque and locking method | Use an agreed assembly check or fixture where required. |
| Customer-supplied components | Condition, quantities, arrival timing and responsibility for discrepancies | Identify any checks needed before assembly begins. |
| Functional tests | Exact method, conditions and pass criteria | Distinguish mechanical fit from electrical, sealing or load validation. |
Decide between an assembly and a matched kit
A complete subassembly and a labelled set of matching components provide different delivery scopes. Define which work remains with the customer and whether disassembly, access or maintenance requirements affect the chosen arrangement.
Use the RFQ checklist to bring these decisions into one controlled enquiry package.
Ready To Start Your Project?
Start With Your Drawings - or Tell Us What You Need
Share drawings, photos or sketches with your quantity, material, finish and target date. We review the available information, clarify technical requirements and confirm quotation timing. Complex or multi-process projects may require additional review.
Discuss confidentiality and NDA requirements before sharing sensitive project files.