This injection mold making project is an electrical switch plastic holder, the material is PC-ABS.
Basic part information
- Part size: 47.64 x 73.59 x 16.59 mm
- Plastic material: BAYBLEND FR3010
- Finish: VDI-18
- Color: black
- Production volume: 10K
Welding lines are a typical defects for injection molded parts with many hole features, such as computer key board typically, the hot resin flow around the little inserts and melt flow meet each other on other side where the welding line occurs, this is how welding line occurs, melt flow temperature always drop while melt resin flow over the mold cavity, that is why the welding line can only be optimized but can not be completed removed if you simply use higher mold temperature, in some other cases, changing gate position would just change the welding line to a less critical location, but for a product similar like computer key board, neither mold temperature or changing gate location would work, as a consumer product, the surface finish is quite critical thing, so as you can see now most of the key board product was painted nicely to cover the welding line defects.
Here is an example we have made for one of our clients from US.
This is a mesh basket, at the beginning, the customer decided to go with high temperature ABS material. As usual, we discussed the part details such as parting line, gate type/location, draft angle, wall thickness and the other potential issues/proposal with the customer before mold making, this is called DFM process.
Recently we had done a succeed mold and molding project for a US company, it's a type of a remote controller, project went smooth but I would like to summarize it and point out a few key points, first we take a look on the project.
It's consisted with front case, back case, cover, and silicone pad, there is a BOM for the whole product, but due to Non-disclosure agreement, we can't give more details how it was designed.Basic part information
- Part size: 80x45x30mm
- Plastic material: ABS /silicone
- Finish: SPI-B-2
- Color: blue/black
- Production volume: 10K
We made one 1+1+1 family mold for the front case, back case, cover, actually the front case and cover are in blue, back case is in black, the question is how to do 2 different color in one mold? -- we design a turntable gate so we can mold one color by sealing the other cavities, by this way we only need one mold, even the molding productivity is a little lower but given the cost of an extra mold and only 10K production volume, this is still an economic way to go.
Plastic injection molded parts have many applications on architecture industrial, such as PVC water pipes, plastic gliders on windows, shelf support, hangers, handles etc. ACO Mold has rich experiences to help customer to customize their own architecture plastic parts.
Here is an example to show you how we work with a North American company from mold design to injection molding production for a glider/slider on windows step by step.
Glider size: 0.6x0.5x0.3 inch
Plastic material: PA66+GF30
Demand volume: 10K-20K/ year
ACO Mold are engaged in injection mold making for plastic packaging housing/cases in packaging industrial, usually plastic packaging housing/cases are made in PS or PC, with high polish surface, which required SPI-A mold surface finish, most common choices for steel are NAK80, 1.2083, 1.2344.
Injection mold making is a customized process, ACO Mold engineers work closely with customer to understand their requirements and make proper solution to achieve the best possibility,we are not simply a mold manufacture to deliver the parts according to design, we offer solutions and deliver satisfaction.
From this project, you can see the product designs from customers are not always the optimized one, sometimes the defects of the molded parts are caused by product design problem, the purpose of DFM analysis made by ACO Mold is to avoid such defects before mold making.
China now is the largest automobile consumer. According to the research of the China Association of Automobile Manufacturers, in 2013 the number of car sales in China market reached 21,984,100 sets, an increase of 13.87%, both car production and sales in China are the largest in the world. Along with the auto industry booming, plastic injection molding for auto parts are growing fast, 90% of automotive parts are produced by injection molds, this is a huge market for China mold making factories.
At this point of time we totally change our policy to accept new plastic injection mold project for China mold makers and summarize following tips we need to know when buying plastic injection molds from China:
- To provide complete inquiries. Complete product specifications and complete injection mold specifications. It include even any small detail as minimum eye-bolt dimension or cooling connector standard.
- When the Chinese factories provide us their quotations, they should provide us a draft of their plastic injection mold design. Clearly, if we do not know the structure of quoted mold, we can not take in consideration their economical quotation.
- The Chinese mold factory must provide us video, samples photos and mold designs for similar projects that they have done previously.
One manufacturer that I know of had axles breaking in the field they traced it back to poorly heat treated and improper material being delivered from China. They got cheap axles, but how much did replacing their entire product lines axles out in the field cost them? If a component is critical to injection mold life or human safety put a stringent check process in place and refuse delivery until a 3rd party can verify this process.
Today I am currently quoting a redesign of an offshore injection mold. The plastic mold met the customer standards to the letter, however the plastic injection mold does not function to demold the parts as would be expected in a North American Market. A plastic molder in a low-labor rate country may find hand demold of a product acceptable. A plastic molder in North America would not want to be hand demolding parts due to high labor cost. Make sure that if you are a North American customer you spec. out what the demolding parameters need to be. i.e. Automatic vs. Hand removal. End of arm tooling, vs drop to conveyor, etc.
Our company manufactures only high quality injection molds in China exclusively for Europe, US and international molders that need injection molds that can run under their conditions but still need to provide competitive quotes to their clients. Including air freight we are typically 50% of the cost of the exact same molds built in the US. We are in fact a US based company and all of our tooling engineers and account managers are professionals with the industry. Our customers get all the advantages and conveniences of working with highly experienced people in their own countries while still enjoying huge cost savings. There is much that we can share with you about solving the mysteries of finding plastic injection molders in China.
I started building injection molds in China, Taiwan, HongKong, and Portugal back in the late 70's. This was when I lived and worked in the US and the molds were to run production in the US. The very same injection molds were quoted by our US and Canadian companies. All included in the analysis of "do we or don't we" build off-shore we always included landed cost in the US, engineering onsite support, sample costs, sample shipping costs, plus anywhere from 10% to 20% add on contingency for final work in the US, depending on the particular mold supplier and our history with that supplier.
All the above being included, if we could not show 25%-30% savings by building the injection mold off shore, it stayed in the US or Canadian mold companies. If the total cost of owner ship is negligible, you certainly shouldn't build it on the other side of the planet. You need to justify the decision based on economics, it's simple.
As internet world rapid development and make world communication more convenience, at same time world trading is also growing. That help more and more Chinese injection mold companies get chance to cooperate with overseas companies, because of China has strong manpower and low payment but it's already 5years ago after 2008 financial crisis and these year RMB's value, Chinese company situation has totally change right now, here has no low payment for manpower but the thinking of China from overseas companies don't think so. Because as economy change most of Chinese companies need to raise employee payment but at same time the PO price from their customers haven't changed. So those forces a lot of Chinese companies to survival on the risk of save cost for high employee payment from reduce the mold quality.