Brass, while relatively soft and possessing excellent machinability, is highly ductile and prone to deformation under heat, making it a typical challenging material for CNC hollowing machining. Before machining hollow, thin-walled, and multi-cavity structural parts, comprehensive preliminary process preparation is essential.
Technicians will disassemble and analyze the part drawings to clarify the hollowing structure, thin-wall thickness, tolerance requirements, and appearance standards, proactively mitigating machining risks for vulnerable structures. Simultaneously, stable H59 and H62 brass blanks are selected, ensuring they are flat, clean, and have allowances made.
Clamping and tool selection are crucial for ensuring accuracy in brass hollowing machining. A precision CNC machining center is selected, and the spindle and worktable accuracy are calibrated in advance to ensure stable machining references.
Based on the structural characteristics of the hollowed-out parts, soft clamping, vacuum chucks, or custom-made fixtures are preferred to fix the workpiece with low pressure and a large contact surface, preventing loosening during machining and avoiding blank deformation caused by rigid extrusion. III. Layered Roughing and Finishing CNC Machining
CNC machining is carried out in three orderly steps: roughing, semi-finishing, and finishing, adapted to the cutting characteristics of brass. Roughing uses layered cutting and sectional material removal to quickly remove excess substrate, uniformly leaving machining allowance, releasing internal material stress, and initially forming the hollow overall structure.
Semi-finishing corrects the roughing and uneven allowance, corrects thin walls, sharp corners, hollow grooves, and other weak structures, further releases cutting stress, and reduces the probability of subsequent deformation through natural aging.
CNC Machining of Brass Hollow Parts: Forming Process and Quality Control Points
After machining, the brass hollow parts need fine deburring and finishing to solve the problems of burrs and curling that easily occur during the machining of soft metals. Fine burrs and copper shavings easily remain in the hollow holes and contour corners of brass; rough grinding should be avoided to prevent damage to the thin-walled structure.
First, the processing personnel thoroughly clean the impurities inside the hollowed-out gaps with a brush. Then, using a fine-grit oilstone and a micro-grinding head, they gently refine the openings, groove edges, and sharp corners to remove all sharp edges and burrs.
Throughout the process, the principle of light and even grinding is adhered to, ensuring the hollowed-out structure is transparent and regular, with smooth and rounded edges, while preventing workpiece deformation and dimensional deviations caused by over-grinding.
Finally, the entire processing flow of the brass hollowed-out parts is completed through professional post-processing and precision quality inspection. The finished workpiece undergoes ultrasonic degreasing cleaning and drying to thoroughly remove cutting fluid and oil stains from the surface and hollowed-out gaps, preventing brass oxidation and discoloration. Depending on product requirements, additional anti-oxidation treatments such as polishing and passivation can be performed.
The quality inspection process uses precision equipment such as calipers, micrometers, and projectors to comprehensively inspect the diameter of the cutout holes, the thickness of the thin walls, the geometric tolerances and the surface roughness. At the same time, visual inspection is conducted to check for appearance defects such as deformation. Once all indicators meet the drawing standards, the product is considered qualified and is put into storage and delivered.
Q1: Where can I get product & price information?
A1: Send us an inquiry e-mail, we will contact you once we received your mail.
Q2: How long will I get the sample?
A2: Depends on your specific items, within 3-7 days generally.
Q3: What kinds of information do you need for a quote?
A3: Kindly please provide the product drawings in PDF, if provide in STEP or IGS will be better.
Q4: What are the payment terms?
A4: We accept 50% as a payment deposit, when the goods are prepared, we shoot photos or videos for your check, and then you can pay the balance. For small quantities, we accept Paypal, the commission will be added to the order. For big amounts, T/T is preferred.
Q5: How to deliver the goods?
A5: We deliver the products by courier company.
Q6: Are you a trading company or factory?
A6: We are factory direct with 17 experienced engineers and more than 50 employees as well approximate 3,000m2 workshop area.
Q7: What shall we do if we don't have drawings?
A7: Please send your sample to our factory, then we can copy and provide you better solutions. If send us pictures or drafts with dimensions(Length, Height, Width), CAD or 3D file will be made for you.
Q8: Can we get some samples before mass production?
A8: Absolutely yes.
Q9: Will my drawings be safe after sending them to you?
Q10: Is it possible to know the operation status of my products without visiting your company?
A10: We will offer a detailed production schedule and send weekly reports with digital pictures and videos which show the machining progress.
