Allotment Gardening Advice Help Chat
Chatting => Equipment Shed => Topic started by: beng on July 26, 2006, 16:28
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does anyone know of a good source for black plastic sheeting other than ebay?
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Try: http://www.kaysdiscountgarden.co.uk/
Also Tesco do cheap perforated plastic sheeting
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1. Injection Molding
In Injection Molding, melted plastic is forced into a mold cavity. Once cooled, the mold can be removed. This plastic molding process is commonly used in mass-production or prototyping of a product. Injection molding machines were made in the 1930's. These can be used to mass produce toys, kitchen utensils, bottle caps, and cell phone stands to name a few.
2. Blow Molding
Blow molding is like injection molding except that hot liquid plastic pours out of a barrel vertically in a molten tube. The mold closes on it and forces it outward to conform to the inside shape of the mold. When it is cooled, the hollow part is formed. Examples of blow molding products are bottles, tubes and containers.
Equipments needed in setting-up a blow molding business are relatively higher than injection molding.
3. Compression Molding
In this type of plastic molding, a slug of hard plastic is pressed between two heated mold halves. Compression molding usually uses vertical presses instead of the horizontal presses used for injection and blow molding. The parts formed are then air-cooled. Prices of equipments used for compression molding are moderate.
4. Film Insert Molding
This plastic molding technique imbeds an image beneath the surface of a molded part. A material like film or fabric is inserted into a mold. Plastic is then injected.
5. Gas Assist Molding
Also called gas injection molding is used to create plastic parts with hollow interiors. Partial shot of plastic is then followed by high-pressure gas to fill the mold cavity with plastic.
6. Rotational Molding
Hollow molds packed with powdered plastic are secured to pipe-like spokes that extend from a central hub. The molds rotate on separate axes at once. The hub swings the whole mold to a closed furnace room causing the powder to melt and stick to the insides of the tools. As the molds turn slowly, the tools move into a cooling room. Here, sprayed water causes the plastic to harden into a hollow part. In this type of plastic molding, tooling costs are low and piece prices are high. Cycle time takes about 40-45 minutes.
7. Structural Foam Molding
Structural foam molding is a process of plastic molding usually used for parts that require thicker walls than standard injection molding. Inserting a small amount of nitrogen or chemical blow agent into the plastic material makes the walls thicker. Foaming happens as the melted plastic material enters the mold cavity. A thin plastic skin forms and solidifies in the mold wall. This type of plastic molding can be used with any thermoplastic that can be injection molded.
8. Thermoforming
In this plastic molding process, sheets of pre-extruded rigid plastics are horizontally heated and sucked down into hollow one-piece tools. When the hot plastic solidifies, its shape conforms to that of the mold.
Tooling costs are usually low and piece prices vary on the machinery.
Plastic molding is a very technical process. It needs experts in this type of manufacturing business for it to be competitive in the market. Therefore, a very scientific and systematic study should be first made before going into this endeavor.
I got this in some site that i research in google hope you will like it guys... Have a nice day to all of you!!!
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Plastic Industry (http://www.mappinc.com)
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how very informative.
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but not very relevant to the original question.
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quite right, grannie,
how about this one.. ;)
http://www.diyplas.co.uk/
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Oh wonderful Qwiz!
I want this one for the chooks run!!!! just hose it off!!!!
http://www.diyplas.co.uk/artificial_grass.asp
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would that be possable? ( I know nothing at all about chickens )
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does anyone know of a good source for black plastic sheeting other than ebay?
I think you should try some plastic molding industries... or rapid prototyping industries for that black plastic sheet.. or try metroplastics.com ...
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Rapid Manufacturing (http://www.metroplastics.com)
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does anyone know of a good source for black plastic sheeting other than ebay?
If you're looking for black heavy duty dpm (which I use for mulching/suppressing weeds) I get mine from B&Q in 4m x 15m rolls that cost around £18 ish, but I haven't bought one since the end of last year when several newspapers were printing 20% off at B&Q vouchers and I threw a couple of rolls in my shop.
If you're interested in some (or something else), apparently there's currentley 10% off virtually everything all this weekend + monday to celebrate B&Q's 40th Birthday + if you spend £50+ they will give you a voucher that will give you 10% off everything for next 2 weeks.