June 2010
24 posts
WatchThat Was A Goodness
WatchHand Crank Extruding
WatchGear Testing 1
Potential Gears.
Heres the potential gears that might drive the extruder. they Currently have a 1:9 Ratio and having two sets combined with this motor from jaycar would be almost perfect RPM of around 100 and should provide enough toque.
Link to Jay Car about the motor -
http://www.jaycar.co.nz/productView.asp?ID=YM2716&keywords=motor&form=KEYWORD
There might be enough material strength in acrylic if...
The Mixer.
The Mixer worked pretty well with HPDE and PET when it was run for about 30 minutes but its really not feasibleA kitchen wizz would probably work better because it would cut rather than munch, but they are expensive for what we might get/use out of it. looked in second hand stores and trademe Heres a quick model of the kind of chopper that would work best for all type of materials and states. Also...
Wire Nichrome Supply →
Extrude some plastic!!
Jason has been trying to extrude some plastic through the screw extruder and see if it has any issues.
In manufacture they use a screw with a variable thread and spacing to increase pressure, move material in different states and maintain temperature within the chamber. So far the best suited is a 8mm wood orger for drilling holes - run in reverse.If this does not work a 10-15mm Coach Screw may...
Variable Temprature Melting Points.
Jason has been looking at the variable temperature melting points and it has something to do with re-melt and amount of moisture within the plastic during flake to melt stage.
If the plastic is not kept below a certain Moisture content the water has a chemical reaction within the plastic and causes it to break down back into its primary elements causing a higher temperature to re-melt again....
Circuit Diagram
Ben has been working on a circuit for the heating component of the extruder with help from Tiago.
The best material to make the barrel out of is brass but we need some kind of heat insulator between the barrel and the electronics. Apparently wood is good.
May 2010
10 posts
Visiting Industry?
Do we want to go visit wellington plastic extruders for more info and ideas? check the list out at: http://nz.vicdir.com/dir-w10015s24347-plastic-goods-manufacturers.htm will call Leda industrial as sugested by Ross to talk about if they do extrusion…e t c
Good Plastic Info →
PET Melting Temperature
Maximum Temperature: 248°F 120°C
Minimum Temperature: -148°F -100°C
Autoclavable: No
Melting Point: 266°F 130°C
Tensile Strength: 4550 psi
Plastic Melting Temperatures
Swiped the following table from Nasa: HDPE about 130 ºC LDPE about 110 ºC PET 250—260 ºC PP 160—170 ºC PS 70—115 ºC PVC 75—90 ºC
PET Experiments →
Mac Attacks wise words
Hey, Sorry i had to leave today. Jeon bin has been researching with extruding a few different types of plastics and heaps of colours for the maker bot up at kelburn . He said he had some PET extruded and it could be a good insight into the process and see whats really required for us. I’m not sure what was talked about but i will just put my two cents in. For initial trials any PET will work...
Recycle bot is Alive!!!
Hey guys,
recycle bot is underway, we have research groups : Plastics research group: Avivid , Jonono, Yauu( melting point, how to crush it, cooling times, blend? sticky? And what you think you should do) Heating Research group: Louie, D.Cmassive, Mack-attack hot crap.( Irons, teflon coating, Cooling how to? talk to Jen about Recycling research and how they doit. ) Precedent recearch...
