What types of plastics can the Model-
Because there are so many different variations of plastics on the market, this question is not simply answered. For each "type" of plastic (e.g. PS, PE, PP, ABS, etc.) there are often hundreds if not thousands of different "grades" to choose from that can vary widely in their processing requirements. Some grades of a particular type of plastic may be designed to melt at a lower temperature, and others at a higher temperature. Some grades may be formulated to flow very easily, and others not so easily. Some grades may have chemical additives or fillers mixed in with the plastic to modify its properties, and others won't. To make it even more complicated, sometimes two different types of plastics are blended together to create a COPOLYMER that has the combined properties of both plastics. Thermoplastic resin manufacturers are constantly coming out with new plastic grades and copolymer combinations, and then discontinuing the ones that don’t sell well. Our machines are designed for mixing and injecting thermoplastic materials, but not thermosets. Thermoplastics re-
When choosing a particular thermoplastic, one important consideration is to make sure the temperature necessary to process it is within the capability of the machine (i.e. 600 F max.). Another important consideration is its melt flow rating (MFR). Plastic grades with a higher MFR usually work best in our hand-
The positive thing about having so many choices, is if one particular resin grade doesn’t work well, you can often find an alternative grade that produces better results. For example, it’s not uncommon for thermoplastic resin manufacturers to offer several grades that are substantially similar to each other, except for a having different MFR. A good website to find and compare the properties (processing temp, melt flow, etc.) of nearly every thermoplastic resin grade on the market is www.matweb.com.
What materials / polymers can I mix with the Model-
Because there is such a wide variety of colorants, fillers and additives on the market, available in many different forms (e.g. powders, liquids, pellets, etc.) we cannot make any sort of generic statement of what is suitable. Successfully mixing a colorant, filler or additive in with a molten polymer will also depend on the polymer itself. If you try mixing materials together that are inherently incompatible with each other, our mixing device will do nothing to change that incompatibility. It’s also important to keep in mind that whatever you mix must also be capable of being injected. For example, although you might be able to successfully mix a thermoplastic polymer with a filler material comprising long fibers, that resulting mixture could still clog the nozzle orifice of the Model-
Notwithstanding the above caveats, we have mixed various types of colorants in various forms (powdered, liquid and pellet), as well as fillers and chemical additives, all with excellent results.We have also mixed different types of polymers together also with excellent results. We have also conducted some limited experiments mixing nanomaterials in with various polymers, and at least so far those results also appear to be excellent, although we do not have a SEM to analyze the mixed samples on a nano scale.
We believe our Model-
Do I need an overhead mixer or is the hand mixing tool sufficient?
A hand mixing tool comes included with the Model-
The hand mixing tool is ideal for stirring a molten polymer before injecting it. Stirring ensures the entire melt in the barrel is at a uniform temperature, and also reduces the time it takes for the polymer to completely melt, which decreases the chance of degradation for heat sensitive polymers. An evenly melted polymer is also easier to inject.
The hand tool often works well for mixing powdered and liquid colorants into the polymer, because they can usually be distributed throughout the polymer matrix easily, without extensive mixing.
An overhead mixer is generally recommended when mixing two different polymers together, or colorants that are in pellet form (i.e. masterbatch), or other types of fillers or difficult to mix materials, such as nanotubes. To get the best results for mixing these types of materials, a higher rotational speed of the mixing blade is often necessary and sometimes for an extended period of time, which is difficult to accomplish with the hand mixing tool.
If you plan to use an overhead mixer with the Model-
What type of overhead mixer is suitable for use with the model-
Our evaluation of different off-
For example, below are two off-
1. Caframo Model BDC-
2. Heidolph Model RZR 2102
Between the above 2 mixers, our choice would probably be the BDC-
Why are there different injection tube capacities available?
Both the Model-
Not surprisingly, the advantage of using a larger capacity injection tube is the ability to make larger parts. However, one advantage of using a smaller capacity tube is increased injection force, because the downward pressure applied by the user is concentrated to a smaller surface area, resulting in an increased force per square inch. This would be particularly useful if the material you want to inject has a low melt flow rating (MFR) or is otherwise difficult to inject. A smaller capacity tube may also be desirable when there is only a small amount of material available to inject, or if the material or the additive mixed into it is very expensive.
It only takes a few minutes to “change over” the Model-
Is it difficult to clean the injection tube and other components?
No. To minimize polymer residue from sticking, the injection tube, funnel tray and injection nozzle are all polished and plated. The injection ram is Teflon coated. The helical mixing blade and components of the material stripping assembly are Teflon coated.
A cleaning tool kit (Item CTK-
Also, since the injection tube is removable, it can simply be detached from the Model-
If you should happen to get any sort of charred polymer residue stuck to the injection tube walls that cannot be cleaned out with the cleaning tool, the nozzle can then be easily detached from the tube, allowing you to insert a tubular brass wire brush to more aggressively clean out the tube.
There is a video posted on our VIDEOS page that demonstrates how to clean the injection tube using the cleaning tool.
What is the largest mold size the Model-
The maximum mold dimensions according to our specifications are: 2.63" H x 4.00" W x 2.50" D (67mm H X 102mm W X 64 mm D).
The mold height is limited to 2.63” because the nozzle is positioned directly above it, but there is some flexibility to accommodate a larger mold width and depth.
The depth of 2.50" could be increased a little if you remove the 3/8" thick adjustable backing plate and then place the mold directly against the backwall of the machine frame. However, your mold would then need to be radiused at the bottom edge to match the (.75”) radius of the inside corner of the frame, where the vertical backwall meets the horizontal base.
The width of the mold could also extend past the 4.00" width of the machine if desired, however if it extends too far, you may need to attach c-
Where is the Mix-