Introduction of Vacuum Forming
Vacuum forming is a type of plastic production, which includes blister and thermoforming. Today we mainly talk about thermoforming (thick sheet vacuum forming) and its related information. The principle of vacuum forming is similar to that of blister, which is the process of heating the positioned sheet to a soft state through an oven, forming a closed space around the vacuum forming mold, and extracting the air from the mold cavity instantly, clinging the sheet to the surface of the mold. After finishing cooling and shaping, formed products can be shown in front of our eyes. For vacuum forming, it is suitable for 2mm-12mm thick plastic sheets for manufacturing. Currently, there’re two material production lines at our factory, and the following video will make you clear how we make the plastic sheet.
Ditai has two sets of extrusion production lines! Each of the raw materials has different characteristics, and which materials will be used should be according to your application. The raw materials can be mixed according to the needs of the product, to fully meet your needs of the product characteristics. Don’t worry, we will give you the most appropriate suggestion. DitaiPlastic – Since 1997! Kindly visit us at: https://www.ditaiplastic.com Mail: firstname.lastname@example.org (click to sent email) WhatsApp: +86 13825780422 (click to open WhatsApp)
Vacuum forming known as thermoforming can be divided into five essential production steps, respectively mold making, sheet extrusion, vacuum forming, CNC cutting, and post-processing. In addition to these five basic processes, painting, printing logos and assembly are also workable for us. In general, Ditai can provide an integrated service from design, production, and development.
Materials In Vacum Forming Process
In the vacuum forming process, there’s a wide range of materials, mainly a variety of colors ABS, acrylic, PETG, PVC, PC, PP, PE, PS, and a variety of modified plastic plates, leather plates, and transparent sheets. What we most commonly use is ABS material. ABS, the abbreviation of Acrylonitrile Butadiene Styrene, is one of the common plastic materials, and it is a kind of thermoplastic polymer material with high strength, strong toughness, and easy to be processed and molded. It can also be combined with other materials to reach different functions. PMMA and PC are two combined materials with ABS. For food containers, we can use food-grade ABS. Most plastic products on the market are designed to be UV resistant. To make our products more durable, ABS+UV or ABS+ASA is the better choice provided for our clients. ABS+UV can meet the requirements for better UV-resistant ability, which is suitable for some products like golf cart roofs, car panels, and antennae, etc. ABS+ASA also has the function of UV-resistance, while another outstanding function is to make the products more durable outdoors. And its price will be higher than ABS+UV. If a product using this material is exposed to the sun for nine to 15 months, its impact strength and elongation almost do not decrease and its color almost does not change.
Also, we can make ABS+PMMA material for bathroom products, like shower trays and wash basins. The surface of ABS Capped PMMA is lighter and it can be more scratch-resistant.In the following content of this article, I will introduce a product produced by using this material. In addition, light-transmissive ABS is often used in the production of display products and lampshades.
ABS V0 is also used for fire-resistant products and some plastic products with high flame retardancy. HDPE is also one of the materials we often work with and flexibility is the most famous property it has. In a low temperature environment, it can maintain a certain toughness, and it is also a kind of surface hardness, with good tensile properties of the material. HDPE used in vacuum forming industry is a common phenomena, such as car parts trays, trolley case shells, etc.
In addition to the material, we can also offer our customers a choice of glossy and textured surfaces. For a glossy surface, it’s a shiny and bright effect on the outer surface. Also, we will apply a protective film to the outer surface of our products to protect them from scratches.
They’re also five textures provided for our customers to choose from. Products from different fields will require different finishes or functions. If some automotive parts are used for the vehicle industry, leather grain pattern is what we commonly use, which shows a premium leather effect.
The other four textures are electronic grain pattern, frosted grain pattern, hair cell grain pattern, and diamond grain pattern. The electronic patterns and hair cell patterns are thicker grain, which will have a rougher effect. The thicker grain protects the outer surface of the product from scratches. A textured surface will have a relatively matt effect compared to a glossy material. On another hand, the frosted grain pattern is thinner and will cause relatively small stretching. For diamond grain patterns, it is commonly found in products such as luggage/travel suitcases and fishing boxes.
The Textures You Can Choose
In addition to the existing patterns, we can also customize patterns. Generally, we will first obtain a piece of the textured sheet from the customer and then we will go on to make a textured roller from this sheet. The cost of the textured roller is around $4300, which will take 45-55 days to complete.
Some Projects We Have Worked On
The above mainly describes ABS and some of its composite materials. In the following, I will explain the more specific materials and the products and projects I have worked on.
The Light-transmitting Display
The first project is a vacuum forming sign for display in the booth. As the inner will install a LED light, the material needs to be light transmission. Before starting the production, we recommend light transmissive PMMA and ABS for clients reference. What we finally use is Light transmissive ABS material, which is hard and not easy to break. PMMA is crisper than ABS, but their price is the same. The material itself is milky white color, when you put this plastic sheet to the light, it will show translucent and light-transmitting effect.
Also, we have made minor modifications to the drawings of the product based on the principles and requirements of the vacuum forming process. Then our engineers will convert the 3d drawing to mold drawing and then move to mold production. The mold is made of aluminum, which is durable and suitable for mass production. For material, the color is not 100% white, it’s creamy white. The following pictures will make you clear how they look like.
Once CNC cutting has been processed, we will move to make the painting to the sign. In the first step, we will make the letter sticker and paint the first painting of PANTONE 9160. The sticker will be put on the sign to avoid underpainting of other paintings. After the positioning jig has been made, we will cover the edges first, and the first painting will be arranged to be made in advance. Then the signs need to wait half a day to a day for the paint to dry.
The second painting is for PANTONE 1795, which is the shiny red color. After two coats of paint, the finished sign is produced. Throughout the painting process, we fully understand the customer’s needs and make adjustments as the product is painted before giving confirmation to the customer. If we check the sign carefully, then you will also observer the letter “B”, the upper hole is each of the letter should be smaller. In the last two months, our client share some pictures of vacuum forming sign applied in his display booth. As you can see the pictures below:
Car Interior Panels
Also, the second project I would like to share is related to some car interior panels. We all know that car interior parts are mostly made of materials covered with leather. In May, we receive several types of car panel samples from a client who sells used car parts.
After analysis, most panels are made by injection molding. As the quantity for mass production is relatively small, we suggest that the designs change to vacuum forming. The design is simple so we just need to make a little modification. In the selection of materials, the customer requires the outer surface of the product to be patterned. According to the grain pattern of the customer’s sample, we found the closest leather grain material. We will use leather material covered with ABS material to make it a composite material. ABS leather sheets are often used for automotive interiors, luggage leather interior panels, medical equipment housings, motorbike housings, bus interior roof panels, instrument panels, etc.
Most of the interior parts of the car are made of leather. We cover the ABS material with a leather grain pattern. The original leather color is more of a matt finish and is black with a touch of grey. As can be seen in the picture below, the whole product has a glossy and shiny effect. This is due to the high temperature heating of the sheet during the vacuum forming process, which has resulted in a change of color, making what was originally a relatively matt surface even shinier.
Another material we commonly used for anti-strath products is ABS+PMMA. PMMA/ABS plastic sheet is a multi-layer composite material consisting of ABS and PMMA. Used in bathroom products, cabinet panels, and door panels, it makes the application tougher and adds gloss to the panels. The superb flow properties also make it easy to process and mold. Also, we have made some car rear wing and cavaran mirror guard protectors with this material.
Last year we started talking to a customer who made mirror guards for campervan. The customer sent us rearview mirrors and protective casings made by thier competitors. According to the sample sent by the customer, we found that it did not match 100% with the mirror guard of campervan, so we first conducted a 3D scan of the Wing mirror, and then made a fully matched protective shell according to the actual size of the rear mirror.
As the inner of the mirror guards needs sticking 3 pads to buffer the impact of the purpose, there’s also a rubber strip will be tightly attach to the edge of the mirror guard. After modifying, the wing mirror will be perfectly match the mirror guard and protect the mirror well. For the material, the sample sent by customer first is also made by ABS+PMMA.But the finished products seems more hard but it will cause the material is crisper a little. The miorr guard we make is more flexible. That’s because we use a different proportion of the amount of added material. If the client would like to make the material more harder, we can also make the adjustment following by our customers’ requirements and make some improvement in the mass production.
Finally the client is willing to accept our suggestion and following the previous material production solution. ABS+PMMA material will make the products with high-glossy surface and scratch-resistance. If you would like to use this material to suit for your products, you can share more details about the function for us and then we can provide some suggestion for reference.
In addition to ABS materials, we often make transparent materials, mainly including transparent PC, Acrylic and PETG. There’s higher requirement for the mold surface if we make transparent products. The mold needs to be made by aluminum block to ensure its high-polishing surface. If the mold is not handled polishing well, it will cause the apperance of the product is not beautiful and has some marks due to the uneven surface of the mold. PC material is with colorless transparent, heat resistance, impact resistance, flame retardant. Also it does not need additives with UL94 V-0 flame retardant performance. It generally use for bulletproof glass, goggles, headlights and so on.
In the vacuum forming process, we need to keep the surface of the mold clean. We should use the air gun to clean the surface of the mold each production. In addition, transparent products also need to be more than ordinary materials for several times to achieve the best product results.When we use PC material to produce the product, the key point is controlling the temperature. Its hermal stability is good and not easy to bake soft, when the vacuum forming machine heating, we need to focus on the suitable temperature to avoid that some parts are not in place.
The above introduction is related to our commonly used material and involved in making material products. In the following, we will introduce more different materials and the problems we need to pay attention to in making the material products, hoping to help your guys learn more about the principle of vacuum forming.
If you woule like to make customized plastic products, please share some details and feel free to contact us at any time. We are pleased to provide our production solution and any suggestion for you.