Questions tagged [plastic]
Plastic (material): materials consisting of any of a wide range of synthetic or semi-synthetic organic compounds that can be molded into solid objects. This includes thermos-softening & thermos-hardening plastics.
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What's the best way to mount many clock hands on a custom clock?
I'm building a custom clock that requires 4-5 clock hands that need to move individually. I've designed it so the hand are to be mounted on telescoping brass axles (that have press fit gears ...
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Injection molding - Probability of plastic pouring into connector
I have some metal pins that I want to be molded in parts of the final assembly.
Meaning that, the mold will be made to accept those metal pins, which are positioned in the mold so that when the ...
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Specific Heat, Pore Fluid In ABAQUS
I want to model a problem that the theory behind is in the "Coupled Pore Fluid Flow and Stress Analysis" context that there is in the ABAQUS online documentation, version 2022. The link to ...
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Create a mechanism to support a speaker in the upper part of an enclosure
I am working on an electronics enclosure.
There will be two parts, the main enclosure and the lid that gets screwed.
In the upper lid, I want to have a support for a circular mini speaker.
The speaker ...
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How is fuzzy velvet-like surface on plastic achieved?
This kind:
It's a very thin layer of very short (<1mm) hairs, coating a hard plastic underneath. I encounter this sort of lining on some mid-tier electronics that pretend to be more classy than ...
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Why can't we dispose of plastic waste in decommissioned oil wells?
As a non-expert, abandoned oil wells appear to me to be perfect solution for ever growing amount of plastic waste we are generating every year.
These underground pockets held crude oil for millions of ...
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I'm wondering if the parts I have ordered to be vacuum casted and made have instead been made using 3D printing
The reason why I'm asking this in the first place is that I have observed striations on the parts I have received.
I was under the impression that vacuum casted parts would not have striations that ...
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Finding alternative for Metal bolted joint in Plastic part
I am developing a design for HDR Brachytherpy interstitial Template that has to be completely in plastics. There is a shaft of 25 mm and length 130 mm, which is held by a plate of 10 mm thickness and ...
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Can I weld stretch film?
I have large areas to cover (84 cm x 70 cm, 150 cm x 84 cm, and 150 cm x 70 cm) with stretch film (22 µm thick, 45 cm wide).
The stretch film is not wide enough so I have to overlap several sheets to ...
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Valox 420 30% glass wear
I am seeking assistance regarding thermoplastic material wear on a new product I am developing.
The attached image is molded out of Valox 420 30% glass. In the left side image, the locking dents are ...
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replacing the sound a small toy speaker makes
not sure if this counts for this community, and im open to suggestions where this would belong but im looking for advice.
i have no experience in working with physical hardware, as the limited ...
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Is this shape possible with injection moulding?
I want to build a DIY case with the connector shown in the pictures below.
As you can see, it consists of a circular plastic that extrudes from the main enclosure. Inside there is something that can ...
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Polymer material selection for injection molding
I'm trying to select injection moulding materials, and need some assistance to find the right products.
I have a component that is made up 2 parts; an inner insert and an outer overmould. Originally ...
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What methods can be used to stabilize a vibratory bowl used for orientation
I have a project where we are using a vibratory bowl to feed in parts to an assembler. The issue I am having is that the calibration sticker on the side is very out and a single line is very difficult ...
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Are there plastics harder than heat-treated steel?
I've been reading that plastics harder than steel have been developed.
The drill guide in the photo is made of heat-treated steel. Is there a plastic hard enough to substitute for heat-treated steel, ...
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What is an appropriate way to compare the impact properties between a plastic and a metal?
I'm currently looking at trying to compare the impact strengths between polycarbonate and aluminum to see which one performs better if made into a box and dropped. My intuition says that aluminum can ...
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Plastics that approach brass and aluminum for strength?
This question is asked out of ignorance, not trying to ask a trick question.
Is there a plastic almost as strong as aluminum or brass, not easily deformed, resistant to flexing, that could be used to ...
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Why are these food stretch films (LLDPE) holding one one-thousandth of the weight in reality than what is expected from the datasheet values?
I am trying to reproduce analytically the results found in this experiment where a weight of 3 x 5 lbs (6,8 kgs total) breaks the cling wrap (LLDPE) which is stretched over a medium size cooking pot.
...
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Help me find a material with low acoustic impedance but high wave velocity
I'm trying to find a material that would have two seemingly opposite qualities. I need something with low acoustic impedance, like a plastic, but also with high wave velocity like a metal.
Here are ...
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What does it mean for a polymer to absorb water and how does this relate to hydrophobicity?
My materials teacher mentioned a polymer that is used for its hydrophobic properties but also can absorb water. How can a polymer do both of these things?
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Expanding a small rubber ring
I have a bunch of small rubber rings that I need to conduct testing on. The rings start at about 15mm ID, and need to expand to 65mm and be held there for months. Right now, my solution for expanding ...
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How can I recycle LDPE or HDPE from plastic mesh tree guards?
I have thousands of plastic mesh tree guards like this one:
The trees are now grown and I would like to recycle them. From a quick search online, they seem made from UV-resistant high density ...
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Fire rated EN 13501-1 B-s1/s2, d0 sheets
I'm trying to learn more about the type of sheets I can get for a project, I would of course go for polycarbonate if not for its price, currently the project with PC will cost \$600-\$700
but I'm ...
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Plasticity (stress(strain)) interpolation in Abaqus
The stress-strain data for a plastic deformation is given in table.
I have two questions related to how that table is treated:
How is data interpolated? Is it piecewise linear or something else?
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What rubber to use to grip stainless steel?
I need to secure a plastic bobbin on a 316SS shaft so it can be wound in a winding machine. There is a potential for undesirable axial and rotational drift that I need to prevent.
My initial thought ...
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What materials could non-flammable (blowtorch resistant) "plastic" submarine furniture be made of?
In a documentary on Russian submarines they show non-flammable furniture that's made of some kind of plastic of foam. They test/demonstrate it with a blowtorch that is capable of cutting metal (they ...
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Alternative to high cost plexiglas and polycarbonate for large project
I am planning the construction of a large scale dodecahedron infinity mirror, and so far the largest cost by far are the glass (or similar clear, hard material) pentagons. Each panel would be screwed ...
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Is there any difference between an-elastic and visco-elastic materials?
Most of the sources that I had read about either talks about anelasticity or viscoelasticity, they don't compare both. From what I have read so far ,both anelastic and viscoelastic materials are the ...
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How to design stiff plastic sheet
I am making a cylinder of polypropylene that must be pressurized (2 bar). The rough dimensions of the current design (A) are 7 cm tall, 5 cm in diameter, and wall thickness of 1-2 mm. The issue is ...
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If I make refillable yogurt and sour cream pots (that I fill as a service), would that be better than buying yogurt in plastic pots and recycling?
I am trying to find out how I can get yogurt or sour cream in an eco friendly way. I know the films on the supermarket plastic pots are currently not recycled, so that's not great...
If I start a ...
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Finding Safety Factor for Plastic Snap Fit Cantilever
I'm trying to get a safety factor of $n\geq2$ for the root of my snap fit beam (pic at bottom of the post).
I have gone through the calculations to get the SF at the root's edge from the geometric ...
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How well does epoxy bond to PETG / ABS vs Wood?
I know that PLA does not bond at all, just peel right off
But i'm wondering about PETG or ABS
Will they bond just as well as wood?
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Best DIY material for a high-torque cog or gear?
I am making a gear/cog to attach to a high torque stepper motor.
I can realistically make it out of the following variety of materials:
3D printer PLA/PLA+ etc.
layered PLA/PLA+ and fiberglass made ...
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Mechanical fasteners made of HDPE?
I need to fasten pieces of HDPE together but I’ve heard gluing HDPE is difficult (after all, glue comes in HDPE containers, and the glue doesn’t get stuck in the bottle).
Using mechanical fasteners ...
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Heat-shrinking vinyl
I want to make a vinyl stencil on a curved surface. I already use vinyl stencils with a vector cutter like Silhouette to make designs on flat surfaces. I also use heat-shrinking tape for insulating a ...
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Increasing torsional-stress resistance of an Auger at its motor-shaft joint
An auger is used to move plastic balls and is rotated by a stepper motor. Due to the balls getting jammed sometimes, this induces stress on the auger at the motor-shaft junction and breaks. Images ...
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Narrowing down injection moulding material selection
How do I narrow down specific values when selecting a plastic for injection moulding?
My part is uniform in wall thickness and thins out where a hinge a present.
Properties:
Will not go under many ...
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Selecting material for plastic hinge
I have designed a plastic part shown in blue that will be injection moulded. The part is a lever that takes 1 mm of movement downward and outputs 6 mm of movement upward. Circled in green is a hinge ...
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Rubber that remains Elastic in Hot and Dry Application
I work for a valve manufacturing company and our customers have an application where very large volumes of hot (200F), dry air pass through our valve. As a consequence, the rubber (carboxylated ...
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Adhesive to connect metal with a coating to plastic that resists mineral oil
I have a peristaltic pump that was having some leaks because of connections between the tubing so I decided to replace it all with a single piece of tubing. Upon doing this though, I observed that the ...
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Salt grinder and corrosion
I am looking for a kitchen salt grinder.
I know salt is an aggressive compound and it needs a little bit of attention when we design products.
Since most of grinders have plastic-made or stainless ...
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Recommendation of different materials for 3D printing flexible parts
I am planning to 3D print this part from solidworks.
I am hoping to achieve a good level of flexibility with the clasps in this part.
Thin circular arc in the Top drawing.
and
Wider circular arc in ...
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Building a coffee maker - food grade, heat resistant material?
Background
I want to build a drip-style coffee maker for fun. My "design" features a sealable cylindrical housing for the water and heating element. Silicon tubes will carry boiling water ...
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IP grade for specific plastic case
I´m designing an access control device and I need to place it in a plastic case so it can be easily installed on a wall, for example.
Also, the PCB will have a special coating for humidity protection.
...
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3D printer printing out cotton-candy like material after repeated use
I recently purchased a JGMaker Magic 3D printer. It worked well for about 3 months [first picture], but now it is having a lot of trouble.
As you can see in the images below, when printing new pieces, ...
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Searching for a material that respons to voltage change
For a project, I need a transparent ball that is rigid, but under application of a voltage changes it's size, like a self-inflating balloon. Because it's rigid, however, and thus would break when ...
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How to get soft touch matte finish on my resin cast parts?
I'm working on a prototype electronic consumer product for which I intend to use silicone molds with polyurethane casting to get the plastic body. I have seen a few products with a smooth satin finish ...
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Does plastic expand at colder temperatures?
After placing a dry solid block of nonporous plastic material in the freezer for a while, I was surprised to find out when I retrieved it that it had expanded globally by a few inches. Which type of ...
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How to get this hydraulic system working and help identifying parts and their function
I have recently acquired a 1982 Arburg 220-90-350 injection moulding machine, mainly just as a hobby to further my knowledge on injection moulding machines and control systems as I plan to modernise ...
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Fix plastic tub (leak) and resist applied forces
I hope I'm not too much off topic here. I'm hoping it can make sense as a mechanical engineering question.
There is a crack in the front of the tub of my front loading washing machine.
As you can see ...
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