We usually make metal dome array or dome sheet with the standard and normal tape (datasheet of PET adhesive ) . But sometimes we still would hear feedback from some customers that dome array can not be sticked firmly and strongly on PCB (print circuit board) or FPC (Flex PCB), see below photo.
Specific reasons are analyzed as follows, wish it would be helpful for your product design..
The dome film sheet made with high dome force and stroke (height) as the customer required, lead to the adhesive can’t be pasted well on board, because adhesive layer will be jacked up.
The adhesive tape area of snap dome array reserved and pasted in the customer’s drawings and specifications is not enough or too little. Generally keep a distance of at least 2.0mm above.
3. The viscosity tolerance of each batch of materials is different. If the material tolerance goes to the lower limit and the above two factors are added, the adhesion may not be very firm.
In general, our metal dome array is unlikely to have such a problem. For these special specifications, we can generally use a more viscous adheisve tape (such as 3M) to solve this problem. We have stronger adhesive materials for some special specifications of the snap dome sheet. However, there is a disadvantage is that it is not easy to tear after sticking, so you should stick to a good position at one time.
Best Technology, your best partner in Asia, is professional for dome sheet and dome switch in China. Please feel free to contact us if you have any question about snap dome.
Many people think that the production of metal dome array is very complicated, in fact it’s not. It’s easy to produce and the cost is not very high. Let me take you through the production process of metal dome array.
As all know, we need to control the production environment of our products well, so before we enter the workshop, we must put on dustproof overcoat, cap and shoe covers, and then be dusted by dust removal system in a closed room.
dustproof overcoat
Firstly, we need to do incoming inspection, raw material of PET adheisve with width, thickness, appearance and tension and metal domes switch with life times , force, diameter, height, burr, resistance and appearance, in order to make sure the snaptron domes are all same standard and meet customers’ requirements.
PET paper
There’re many kinds of PET paper with different colors, such as white, transparent, black, gold, etc. The gold one is most expensive and few customer use it. We often use transparent and white adhesive.
PET paper
There are two methods to make snap dome array, one method is by laser-cutting, that produce with small qty, a litter longer lead time and higher unit cost, but could save tooling cost; And another method is by machine with tooling, that we can produce big quantities and save manufacturing cost in this way, but the customer need to pay tooling fee.
laser cutting machine with tooling
Now please let me briefly describe the process of how to make dome array by laser cutting. Laser cutting, the temperature of its operation can be 500 degrees. The cost for this manufacture is lower, but the processing charges is a little bit higher.
Firstly, we need to laser cut spacer hole (dome hole)
laser cutting
Second, do first article inspection. Put dome array on assembly Jig, check whether the snap dome hole on assembly Jig and spacer hole on spacer overlap.
assembly Jig
Third, we can place other materials on the top of spacer to meet customers’ requirement after spacer production is finished, such place mylar, silver paste, rubber glue or LGF layer. No fingerprints are allowed to be on the spacer, so we’ll gently scrub the spacer by alcohol, and we can have pony-size spacer after machine cutting.
Coverlayer machine
After that, we need to laser cut outline and air channel.
laser cut
And then, Dimensional measurement for this dome array.
There are dots on fixture, when the fixture is operating, we will put the snaptron domes on it, and the dots will fix the metal domes on them. Put the spacer (sticky side) on the top of Snap domes in dots until all the metal domes switch adhere to it. This is what metal dome array first looks like.
fixture
Afeter assemble sanptron dome on array, we need to check whether have double metal domes. Normally we use magnet to check it, will put metal dome array on powerful magnet, if there’s needless Snap dome, it can be attracted away by magnet.
magnet
Or use Electrical measuring fixture to check double metal dome, but the customer need to pay the fixture cost by themselves.
Electrical measuring fixture
After check the doubel metal dome, we’ll settle release paper on metal dome array. Finally we need to do finished product inspection and Pack & Shipping.
Pack & Shipping
Do you know how to make dome array by laser now after reading this article? Please feel free to contact us if you have any question. And I will introduce how to make dome array by machine in next article, please pay attention for us always.
Best Technology is your best partner in Asia, we are always here and waiting for your coming warmly.
Life cycle of metal dome is a key point all people concerned, but do you know why each manufacturer has a different result about life cycle? Some even has very big difference?
Do you know which factors will affect the life of metal dome? You will get the answer after read below words.
The Second factor: Life test method. Maybe you’ve been in this situation, you ask same metal dome from different supplier, but with different life cycles and you are confused about it. The reason is that when we use different life test method, such the diameter of test probe, material of test probe, test speed, test force to test the metal dome, the result will be different.
For example, under the same test speed and force, tungsten steel test probe has a different test result compared with silicon test probe. It’s easy to guess who has the tougher test conditions.
So the same principle, 1.5 times test force has different test result compared with 1.1 times test force.
The Third factor: The click ratio.When click ratio is too high, the rebound force will more lower, thus the metal dome is easy been sunk after long time pressing, so it is easy to reduce the life of metal dome.
Performance
The Fourth factor: Accuracy of assembly. The life is the best when we always press the center of metal dome, but the large deviation of assembly, it will cause us to miss the center of metal dome and reduce the life of metal dome, and also will have other issues.
metal dome assembly
And the life time are also related with the shape, height of metal dome, tooling produced, and operation habits. Usually round type will have better life than four legs and triangle, higher height with shorter life of metal dome; The more precise the mold, the better the life; If the operator press the dome with excessive force for long time, its will reduce the life of metal dome as well.
metal domes
After reading this article, you must know more about metal dome now. If you still have any doubts about life cycle of metal dome, welcome email us sales@metal-domes.com or call us +86-755-2909 1601, we are happy to discuss more with you.
Can metal dome array bear high temperature oven? The answer is no.
Why do some customers have this requirement? That is because they need to assemble metal dome array(dome sheet) before welding, it would need bear over a high-temperature(over 200 degrees). However, the maximum temperature of the metal dome array material can bear is 125 degrees. So the material will be melt after high-temperature oven, this is certainly unacceptable.
If this requirement must be obeyed, we can change to use one material which can bear high-temperature. However, the difficulty and cost of this kind of material will get much higher than normal one. Therefore, it is recommended that we can assemble dome array(dome sheet) after welding, this is a very reasonable and convenient way.
If you have any doubts and you have a better way, please contact us.
Some customers will ask us if we want to place entire sheet dome array on PCB panel at one time, in order to save time and assembly cost, is it possible? How to place it and what we should do?
Today I’d like to share some basic information for that. Firstly we need to know the structure of dome array, please see below two structures: one sheet dome array placing and single dome array placing, you could see there is only a little difference between them, add one more layer transfer film.
the structure of dome array
It’s very simple to assemble entire sheet dome array on PCB panel at one time, same as placing single dome array at one time, just one more step and here are some basic steps:
1) Clear the PCB, make sure there’s no dirt, dust, or any other contamination;
3)Put entire sheet dome array on PCB panel by manual.
putting dome array on PCB
4)Press surface of dome array to make sure it adhere on PCB firmly, then peal off the transfer film from top side.
putting dome array on PCB
5)Finished the assembly.
pcb
Please note the bonding force of glue will become more and more stronger after about 24 hours, without any movement, pressure, etc. It means if after 24 hours, you cannot peel off dome array from the PCB, without damage the dome array, because the peel strength at that time will be extreme big comparing to initial value.
And in order that you could understand more clearly about it, we take a video about it, please see below video for details.
How to assemble entire sheet dome array on PCB panel at one time?
I think you will have another question, whether only this way could place one sheet dome array at one time? The answer is no. I will share another method to you in next article, please Stay tuned for more news about us.
For some metal domes, they sounds crispy when pressing them, while others not. Then what plays the role during the process? Now let me introduce it to you.
metal domes
Virtually, there is a calculation method, which is, using the value after trip force minus rebound force to divide the trip force, then we will get the hand feeling percent of metal domes. The hand feeling percent value is generally 50%(±15%). The larger the percent, the louder the sound and vice versa. However, the hand feeling percent can not surpass 70%, as a general rule. This is because, the rebound force will get less if the hand feeling percent is too large. It is easy to make metal domes concave if pressing for a long time.
At Best Technology, customers can order metal domes with different hand feeling percent, according to the different applications of products.
If you have any queries, comments or suggestions, welcome to contact us.
We are pleased to announce that Best Technology has recently completed 14 years of its glorious journey. Every step is worthy of being celebrated. On June 26, 2020, our founder, Peter, Emily, group leaders and all the employees spent this unforgettable festival together.
Best Technology team
On Best Technology successful journey, Peter emphasized- “The past 14 years have been a period of growth and a learning experience for us as we went through several trials and errors till we deliver successful business. Today we are proud of the fact that our employees can make great progress day by day after training with us and feel confident taking on tough project-related challenges,many thanks for all the endeavour from employees and thanks for the great support from our suppliers and customers. Best Technology’s continuous development can not do without them.”
We have come a long way from 2006 when we started off with just 1 people(Peter). Today we are proud to announce that we have nearly 100 employees and many sister companies spread all over China mainland and also have customers in over 150 countries around the world.
number of employees
From above, it is evident that there has been a staggering growth in the number of employees in the span of 14 years. This enhanced employee strength has built the roadmap to Best Technology’s success.
annual sales volume
The above graph presents our company’s growth against the years 2006 to 2020. It can be seen that the growth rate is very high from 2006($8000) to 2019($6560,000). At this year 2020, Best Technology still keeps growing with increasing sales volume in spite of COVID-19 outbreak.
Best Technology’s unique journey has been a brick-by-brick progress and has entailed years of efforts. Our company’s commitment in becoming world class distinctive solution of printed circuit board and metal domes in 2025 has paved the way to the series of milestones achieved. These are equally appreciated by the correct leadership of our chairman, Peter.
The primary aim of our company has been to equip the professionals with all possible accoutrements to tackle on-job challenges. Today’s ever changing face of businesses demands deeper knowledge, quality, and on-time delivery. Customers are always looking out for continuous and improved delivery. The best means to achieve the same is to keep improving.
Birthday cake
We will continue our journey towards innovating the new ways of learning, delivering excellence to the customers and lending a hand to achieve professional goals.
What’s more, Best Technology’s 14th-year anniversary celebration is a solemn procession of efforts and dedication of the trainers and staffs who have spent their quality time to provide the best services and meet more expectations of the ever evolving PCB world.
Best Technology, a China- based assembly manufacturer will be exhibiting at electronica Munich2020 in Bavaria, Germany at booth No. 623(Hall B1) from November 10, 2020 to November 13, 2020(Western Time). Actually, we have participated in this exhibition for continuous 2 years. Here are some pictures for your reference.
exhibition
exhibition
exhibition
exhibition
At our exhibition booth, attendees will be able to learn more about our company for PCB manufacturing and PCB assembly technology.
For interested professionals, Best Technology had on hand experts to offer detailed insights and experience on PCB assembly, covering PCB prototype and low/high-volume production. For more information on PCB assembly and fabrication, welcome to visit our booth.
You are warmly welcome to see how we can manage the components wastage and efficiency to help save your time, money and energy.
About electronica Munich:
Electronica is the international trade show for electronic components, systems and applications and shows the full range in all its diversity in width and depth as the world’s leading trade fair. It reflects the high degree of innovation throughout the industry. Exhibitors and users in the areas of systems, applications and technologies of electronics can receive the information of the latest innovations and developments in the fields of system peripherals, power engineering to printed circuit boards or EMS.
Welcome to visit us at Booth 623 from November 10, 2020 to November 13, 2020(Western Time).
As we all know, a lot of products can use metal domes. Some customers will buy bare metal domes, then they assemble themselves, and also have many customers let’s make it as metal dome array (metal dome with adhesive together), then they only need to paste to the products directly. it’s easy and convenient to operation(https://www.metal-domes.com/blog/2013/08/01/how-to-assemble-metal-dome-array-on-pcb/. But some customers may not know how to assemble the metal dome into the Mylar (also named cover layer or dome retainer) and are interested in it, today I’ll tell you the answer to this question, hope it’s helpful for you.
Our company could custom design Metal Dome Array, and one of the process for making dome array is to assemble metal dome, which is attached to the Mylar (cover layer or dome retainer). We have two method to assemble it, today I’d like to introduce one method: Semi-automatic rocking machine, Please see below detailed introduction.
Semi-automatic rocking machine
Semi-automatic rocking machine: This is done by shaking the metal dome into a assembly fixture and then manually attaching the Mylar (cover layer or dome retainer) to it. the metal domes is shaken around 6-8 s. and different shapes of metal domes is set for different shake time. For example, the circle metal dome is 6s, and the four-leg metal dome is 8s. the number of metal domes put into the machine at a time is about 20k.
The process video of assemble metal domes into the Metal Dome Array using Semi-automatic rocking machine
The assembly fixture should be customized according to the customer’s product drawing with dome positions, then metal domes in the fixture can be coincident with domes hole of the spacer. then assemble the domes into the Mylar (cover layer or dome retainer).
Dome Array before assembled metal domes
Assemble fixture
Dome Array after assembled metal domes
In addition, maybe you will have a question, why the metal domes fell into the fixture hole automatically by shaking, but they don’t move and shift. Because there are a lot of small tubes and suction vents under the fixture, it can suck the domes in and stick it in the right place.
Wish you have understood how to assemble Metal Dome into the Metal Dome Array after reading this article. I’ll continue with the second assembly method in the next time, if you are interested in it, welcome to continue reading.
Regarding HS code and duty rate of face masks in some major countries, we collected some information in main trade partners (US, Japan, EU, Korea, Taiwan, Australia, New Zealand) of China. This is aimed at the face masks such as personal protective masks without special function components, including medical face masks and disposable face masks. All of below information were published by the custom officially.
US:
According to Harmonized Tariff Schedule of the United States, HTSUS, the HS code of face masks in the US is 6307909889. And the duty rate imported from China is 7%. Regarding tariff imposed, according to announcement from the United States Trade Representative on March 12, 2020, the tariff is excluded for the face masks belonging to this HS code since September 1, 2019. Since then, all the face masks imported from China has been exempted from tariff. You can refer to the below chart for more information.
face mask tariff
Japan:
The HS code of face masks in Japan is 630790029. The duty rate imported from China is 4.7%. To learn more, see below:
face mask tariff
EU:
The duty paragraph for face masks imported from China in EU is 6307909899 and the duty rate is 6.3%. You can see below for more information:
face mask tariff
Korea:
The duty paragraph for face masks imported from China in Korea is 6307909000, and normally, the tariff is 10%. However, from March 18, 2020 to June 30, 2020, Korea has been suspending imposing tariff for face masks from China(0 tariff currently), see below for more information:
face mask tariff
Taiwan, China:
The HS code(also referred to as duty paragraph) of face masks imported from China mainland in Taiwan is 63079050.
And, the duty rate for face masks imported from China mainland is 7.5%. However, from February 27, 2020 to May 26, 2020, provisional tax rates (also referred to as“flexible tax rate”in Taiwan area) for face masks was carried out in Taiwan area, i.e. the tariff is zero. You can see below for more information:
face mask tariff
Australia:
The HS code of face masks imported from China in Australia is 63079099 and the duty rate is 5%. See below for more information:
face mask tariff
New Zealand:
The HS code of face masks imported from China in New Zealand is 63079028. Zero tariff is applied to the face masks imported from China according to “New free trade agreement”. See below for more information:
