Slecting the right precise machining process

For precision machined parts,the precise machining process directly affects the quality of products,according to different tolerance requirements to write different precise machining process, to ensure the quality of machined parts, a good machining process is very important.

SYM Precise Machining Process

At SYM Precision Machining, our operation standard is the production drawing provided by the customer. Due to meeting the tolerance requirement of the drawing, write the most economical precise machining process, we require the professional technical level of the process engineer to be very high.

1. According to the size accuracy of the drawing to determine the cutting method, such as turning, milling, grinding, wire cutting and EDM, etc.

2. According to each cutting charateristic to determine the process, for example, machining the parts as below picture, the precise machining process would be.

1) Turning outside
2) Drilling the center hole
3) Machining end surface
4) Chamfering
5) Deburring

Precise Machining Process - Turning 

3. In order to improve the production efficiency, reduce the damage of parts, but also consider the times of clamping, as far as possible to reduce the times of clamping parts in the machining process.


The same part, according to the different quantity of production, its process is also different. CNC machining is commonly used for mass production, the traditional machining is generally used for small quantity production, the cost would be higher if need use CNC machining for small quantity production.

The modification and supplement of precise machining process regulations must go through careful discussion and approval.

10 tips for thread tapping in precision machining

Unlike most commonly used turning, milling and drilling tools, the cutting edge and the opposite surface of the tapping are relatively weak, and the cutting edge is prone to collapse or crack, especially when processing steel materials.

Therefore,let's learn 10 tips for thread tapping in precision machining.

1. The hole of the bottom hole of the thread on the workpiece should be chamfered,both ends of the thru thread hole should be chamfered.

2. The position of the workpiece clamp should be correct, try to make the centerline of the threaded hole placed in a horizontal or correct position, so that the tapping can easily judge whether the tap size is perpendicular to the plane of the workpiece.

3. At the beginning of tapping, try to put the tap straight, and carefully check and correct the position of the tap.

4. When tapping, every 1 / 2-1 turn of the tapping, it should rotate about 1/2 turn, so that the swarf can be easily discharged.

5. When tapping blind thread holes,to drop out the tap and remove the swarf in the hole.

6. When tapping the screw holes of plastic materials, lubricating coolant should be added. For steel materials, motor oil or concentration-bound emulsions are generally used.

7. When changing the screw tap during the tapping process, you must first screw into the thread hole by hand. When you can no longer screw in, continue to tap. When the tapping is completed, it is best to drop out it by hand to ensure that the quality of the tapped thread is not affected.

8. When tapping by machine,the screw tap and thread hole should be kept coaxial.

9. When tapping by machine,the calibration part of the tap cannot be all over, otherwise,it will produce messy teeth when the tap is dropped out.

10. When tapping by machine, the cutting speed is 6-15m/ min for general steel, 5-10m/min for quenched and tempered steel,2-7m/min for stainless steel,8m/min for cast iron.

Custom CNC Machining in China

What is Custom CNC Machining?
Do you have a good supplier who can provide custom CNC machining services?

Custom CNC Machining---According to your requirements, using computer numerically controlled (CNC)  milling and turning machines to produce custom parts.CNC Machining is a fast and cost-effective way to make a few precision prototype with plastic and metal material.the cost is a little high than extrusion, pressure die casting etc process.

SYM Precision Machining is a leader in Custom CNC Machining Services in China,established in 1997,with advanced equipment and professional staff,using our 3, 4 and 5-axis CNC machining centers,CNC lathe to offer you custom machined metal and plastic components. CNC machining services for rapid prototyping and production parts.

Custom CNC Machining Parts from SYM Precision

Advantage of custom CNC machining

1. Precision
You will get high precision tolerances +/-0.001"-0.005" for custom machined parts.

2. Flexible customization
According to your requirements, select from a variety of dimensions on solid metal parts, and plastic parts, built to precise design specifications.

3.Material selection
Custom CNC machining offers a wide variety of materials.we can provide you with customized raw material as required.Such as stainless steel,carbon steel,aluminium alloy,cooper alloy and plastic,etc.

4.Fast turnaround
Rapid machining,large quantities of customized products can be obtained in a short time.

5.Low investment in tooling
Once a tool path is created and a machine is programmed, it can run a part 1 time, or 100,000 times. CNC machines are built for precise manufacturing and repeatability which makes them cost-efficient and highly scalable.

CNC Machining is crucial in many industries such as aerospace and defense, automotive, energy, industrial machinery, medical, robotics.

Please don't hesitate to contact us for your custom machined needs,you will get qualified machined parts on time and win more projects.

First look at the mask for coronavirus

Today, the epidemic has spread to more than 100 countries around the world, and masks will become the biggest hot product in 2020. In just two months, many logistics providers,factories, sellers,and platforms have transformed into mask sellers. Too many people have experienced this,the sellers of masks who claim to be in stock have delayed delivery after paying, delayed for various reasons,even worse,the sellers took the money and closed the business,you can never reach them again. The news reported that there were hundreds of mask fraud cases.

Demand exceeds supply, high-quality factories that meet certification and qualifications have basically been requisitioned by the government,giving priority to the supply of medical systems and severely affected areas (Wuhai,Hubei province). About mask for coronavirus,how many details do you know?

China is a big country in the mask industry, producing about 50% of the world's masks, before the epidemic,the maximum daily output of Chinese masks was more than 20 million. The fastest mask production speed is 120-200pcs per minute, but a standard process of analyzing and disinfecting takes 7 days to 15 days. Because the medical mask is sterilized with ethylene oxide, after the sterilization, there will be residual ethylene oxide on the mask,which not only stimulates the respiratory tract but also carcinogens. So the residual ethylene oxide must be released by analytical methods to meet the safety content standard. After passing the test, it can be put into the market.

The three major mask industry bases in China, Hubei Xiantao, Henan Zhengzhou, and Jiangsu Yangzhou. From the perspective of the industrial chain, manufacturers of upstream raw material,PP Non-woven fabrics, Meltblown fabrics, nose bridge strips, ear band materials, and mask production equipment and midstream mask manufacturing companies are mainly concentrated in the Yangtze River Delta region, and downstream distribution companies are too scattered.

Classification of mask

1.Classified by scope

  1.1 Medical mask: medical ordinary masks, medical surgical masks and medical protective masks.

1.2 Particulate matter protective mask: industrial use meets GB2626-2019 standard, special labor protection products safety mark (LA certification), if used for anti-fog and haze need to use insert type, with GB/T32610-2016 standard.

1.3 Thermal mask: suitable for winter wear, just need to meet the relevant standards of fabrics.

1.4 Other special industries mask: such as chemical industry,etc.

2. Classified by material

2.1 Gauze mask: Gauze mask is still used in some workshops. the requirements of GB19084-2003 standard is low, and they can only protect large particles of dust.

2.2 Non-woven mask: Most disposable protective masks are Non-woven masks, which are mainly based on physical filtration and electrostatic adsorption.

2.3 Cloth mask: Cloth mask only have a warming effect and have no effect of filtering small particles.

2.4 Paper mask: Suitable for food, beauty, and other industries, with good air permeability, easy to use and comfortable, the paper used follows GB/T22927-2008 standard.

2.5 Mask made of other materials, such as new material for bio-protection filtering.

3. Classification by wearing method

3.1 Head-mounted: Suitable for workers who wear for a long time in the workshop.
3.2 On-ear style: Easy to wear, suitable for frequent wearing.
3.3 Neck-wearing type: S-hook, some soft material connectors, connecting ear bands are converted into a neckband type, suitable for long-term wearing, more convenient for workers such as wearing hard hats or protective clothing in the workshop.

4. Classification by shape

Mask is divided into three types: flat, foldable, and cup-shaped. The flat mask is easy to carry, but have poor adhesion; folding mask is easy to carry,cup-shaped breathing space is large, but not convenient to carry.

5. Classification by protection level

Different countries and industries have different standards, which are divided into different protection levels according to different particle filtration efficiency.

Chinese standards of mask

GB2626-2019 This standard filter element is divided into two categories (KN and KP) according to the filtering performance. This type of mask can block the virus for a short time, but it cannot be used to contact patients who may have splatter or contact the patient for a long time.

GB / T32610-2016 technical specifications for daily protective mask, which are standards for the civilian mask.

YY / T0969-2013 This standard is an industry-standard for disposable medical masks. Ordinary medical masks meet this standard.

YY0469-2011 medical surgical mask is the industry standard for medical surgical masks. It is suitable for disposable masks worn by clinical medical staff during invasive operations and other procedures.

GB19083-2010 medical protective mask, this standard applies to medical work environment, filtering particulate matter in the air, blocking droplets, blood, body fluids, secretions, etc.

Prevent and control Coronavirus for safe production

How to prevent and control coronavirus is very important for safe production at present.

In the spring Festival of 2020, the new virus (COVID-19) quickly attacked major cities across the country. As the Spring Festival holiday, most of our workers have returned to their hometowns. However, this year's Spring Festival is not destined to reunite as before. Traffic was controlled everywhere, the holiday extended, everything came so suddenly.

SYM Precision actively cooperated with the local government to implement the production resumption system during the epidemic.
Started open to work smoothly on February 10th, and till now, there are 98% workers have returned back to work,the factory's productivity has returned to normal. To this end, we have made many efforts to ensure safe production.

1. All work areas are regularly sprayed and disinfected.Keep ventilate workshops, offices and living areas.

2.All staff must wear mask, accept body temperature tests and make a record when entering and leaving the factory.

3.All outsider are not allowed to enter the factory area,suppliers deliver the goods stopped outside the factory and forward to SYM staff.

4. During the epidemic prevention and control period, customers are temporarily not accepted to visit.

5.For maintenance the equipment,the outside maintenance personnel must confirm the address and security code information to SYM HR department in advacne, all thing meet to control requirements,can be enter to factory under accompanying of SYM HR person.

6.All couriers are sent and received in the front of guard room uniformly.The demand person will go to the guard room to place and receive them by themselves. No courier personnel can enter the factory area.

7.All staff carry out staggered meals in three batches, scattered seats, and sat in one direction (could not sit face to face), only take off masks during meals. Don't talk during meals.

Till now all staff at SYM Precision are safe and health.We believe that we will defeat the virus soon and welcome a warm day.

Choosing the Right Material for Aluminium Machined Parts

Choosing the Right Material for Your Aluminium Machined Parts.

There are many kinds of aluminium alloy in the market,only 7 kind aluminium alloy be used commonly for precision aluminium machined parts.


AL6061

The main alloy elements of AL6061 are magnesium and silicon, with moderate strength, good corrosion resistance, weldability and good oxidation.It is widely used in various industrial structures requiring high strength and antimicrobial resistance.
Generally the internal stress of T6 is bigger, the processing will be deformed, and the most suitable state should be T651.

AL7075

AL7075 materials are generally added in a small amount of copper, chromium and other alloys,It is reputed as the most excellent product in aluminum alloy, with high strength and far superior to any soft steel,Easy to process and good wear resistancee,but it can't be soldered and it's very anti-corrosive,it's better used with anodize.

Used for high - voltage structural parts,Such as aerospace, mould processing, mechanical equipment, tooling and fixtures industry.

AL6063

AL6063 material is a low-alloyed al-mg-si high-plastic alloy.It has excellent thermoplastic and can be extruded into complex structure at high speed,thin wall, Various shapes of hollow and forging parts.
Widely used in building aluminum doors and Windows, curtain wall frame,heat sink parts.

AL5083

AL5083 material is a high - magnesium alloy. It has good strength, corrosion resistance,weldability and cutting ability in non - heat treatment alloy,the surface is beautiful after anodizing.
Excellent corrosion resistance makes 5083 alloys widely used for marine applications such as ships and welding of automobiles and aircraft parts, subway light rail.

AL5052

5052 aluminum alloy belongs to al-mg alloy,with good corrosion resistance, good welding, good cold processing, and moderate strength.
Used to make aircraft fuel tanks, tubing, and traffic vehicles, the sheet metal parts of the ship,electric shell.


AL6082

AL6082 aluminum alloy belongs to Al-Mg-Si alloy,It has medium strength and good welding performance and corrosion resistance.Easy to process and easily coated.
Mainly used in transportation and structural engineering industries. Such as bridges, cranes, roof frames, transport aircraft,carrier etc.

AL2024
This is a high strength hard aluminum, which can be strengthened by heat treatment, and is of medium plasticity in quenching and quenching.Resistance to corrosion is not high, and anodizing treatment and coating method or surface are used to enhance the corrosion resistance.
It is mainly used to make all kinds of high-load parts and components (but not stamping parts) such as the skeleton parts on the plane.

Know more details please read SYM Blog.

Advanced Precision Machining Manufacturer in China

Advanced Precision Machining Manufacturer in China.

------2019 summary of SYM precision machining.

SYM is an advanced precision machining manufacturer in China.With over 20 years of experience, our facility is a high close tolerance machining shop,with advanced equipment and professional staff. SYM precision machining team is here to support you on mechanical project forever.

Last year, in 2019,SYM increased another 4 sets of 5 Axis CNC machine,DMU50,The Universal Milling Machines of the DMU Series are offering the economical entry into  5-axes machining up to  5-axes simultaneous machining.The rigid swivel rotary table allows a swivel range up to 110°,With spindle speeds up to 20,000 rpm the DMU is suited for high precision complex machined parts.

5 Axis CNC Machining Shop

With other advanced equipment,3 axis CNC Milling,CNC Lathe, Grinding machine,Manual milling and EDM wire custting machine. You will get all custom machined service, such as  CNC Milling , CNC Turning, Manual Machining, Grinding, Wire Cutting and Mechanical assembly works.

3 Axis CNC Milling Shop

Please don't worry about the MOQ, SYM can service for you from 1pc to 10K pc. At SYM precision machining, we have three machining team to match customer's different requirements.

Team I, The main work is for some samples development, rapid prototyping parts.The order Qty' is 1-2pc of each part, lead time is 7-10 days.

Team II, the main work is for some small quantity orders, many types of products with small Qty', use manual equipment, CNC miller, Grinder, Wire Cutting, EDM,etc. The order Qty' is 10-100 pc of each part. The lead time is 15-21 Days.

Team III,The main work is for mass production, some big quantity orders. Used equipment CNC Lathe,CNC Miller and Automatic Lathe. The order Qty' is 500pc-10000pc of each part. The lead time is 25-30 Days.

There must be a work type for your needs,if you want to get high qualified machined parts, please don't hesitate to contact us, the advanced precision machining manufacturer will help you to win more and more projects.

How to reduce the deformation of machining parts?

In machining process, the deformation of machining parts often happened ,and it’s difficult to solve. In order to take corresponding measures, let's study the reasons.

1.The material and structure of machining parts 

The degree of deformation is proportional to the complexity of shape , length ,width and wall thickness. And it’s also proportional to the rigidity and stability of the material. Therefore, when designing the parts, we should reduce the influence of these factors on the deformation. Then ,for some parts with large structure ,we should design a reasonable structure to reduce the deformation.

2. The clamping

First, we need to choose the right clamping point. Then, we should select proper clamping force at this position, and keep clamping point and the supporting point in line .So the clamping force will act on the supporting point. Importantly ,the clamping point should be close to the machined surface as far as possible, and select the position where the force is not easy to cause the deformation.

And we need to pay attention to the order of clamping force when there are several clamping forces on machining parts. First ,we should act the clamping force of machining parts and the supporting point, then act the clamping force of the cutting force.

Then, we should increase the contact area between the machining part and the fixture and use axial clamping force to enhance the rigidity of the machining part.

3. The processing

In the process of cutting, the machining part will produce elastic deformation due to the effect of cutting force. For similar deformation ,we can adopt harp cutting tool .On the one hand ,it can reduce the resistance between the tool and the machining part , on the other hand, it can improve the heat dissipation ability of the tool when cutting machining parts, thereby reducing the residual internal stress of the machining parts.

The heat generated by friction between cutting tool and machining part will also deform the machining part . Generally, we can adopt high speed machining to reduce deformation effectively.

In order to ensure the accuracy of machining parts, we should use a reasonable amount of cutting. And When machining thin-walled parts with high precision, generally, we will adopt symmetrical machining . Because it will balance the relative stress on both sides ,achieve a stable state and make the machining parts that after machining smooth.

What to consider during Copper Machining Process?

Copper is high purity, dense tissue material, with low oxygen content, Pore-free and excellent electric conductivity,suitable for precision machining, has good thermal conductivity.But the strength, the hardness is less.a large number of products are used to electric industry.

Since the material character,we should consider below point during precision machining process.

1. Soft material,easy to stick tool,the tool knife be used should be very sharp.

2. Small feeding with high speed.

3. For complex product,complete all dimensions include thread holes by 5 axis CNC machining to save clamp times,avoid scratch during several machining steps.

4. For some mark letter requirement,it's better marking by CNC machining,the appearance is not good if do it by laser marking.

5. Finish.generally do nickel plating for copper product to avoid surface oxidation,if without any surface treatment,it's better to put the copper machined part in vacuum plastic bag after cleaning process.

8 Top way to save money on precision machining

keep cost-effective design to reduce costs and save money on precision machining.

1.Material select

Select raw material with good machining performance,such as AL6061,Mild steel.
On the premise of ensuring the performance of the product,avoid expensive materials.

Size of material，try to use the material thickness (diameter) available on the market,especially for tube,if can find suitable size of tube for your product without machining inner surface,that would save more money.

2.Order Quantities

Order large quantities of same part to reduce unit price.For a small number of orders, if need to use CNC machine, the cost will go up more.Because each kind of product be done by CNC machining including programming,fixture making, machine commissioning, these labor costs be calculated in the unit price of the product.

3.Structural design of parts

Keep simple shape,the simpler the geometry of the parts surface,the better the machining process.Split up complex parts,especially for parts with deep pockets or multiple faces,may design and machining as separate simple parts,then weld or bolt together.

4.Internal corner

Use an in side corner radius 0.03" Min for tool diameter.

5.Relief groove

Gear,thread, keyway processing must have a relief groove,otherwise the tool will be damaged. Keyway, pin hole is arranged in the same direction,the height of the orifice should be the same plane,for one installation.

6.Hole depth

If can use thru hole,don't use blind holes.
Avoid deep holes (depth is 10 times larger than diameter.

7.Tolerance management

Limit tight tolerance,the lower the average manufacturing accuracy of the parts, the better the structure of the
product.According to the function of product requirement,assign tight tolerance to critical features,keep all other feature as standard tolerance +/- 0.005".

8.Surface roughness

When it comes to surface roughness specifications,use N6~N7 is easy to reach by turning or milling, up to N5,the surface would be done by grinding or polish,the cost would be increased 30%~40%。