FreeShip- Plastic Vibratory Media, 3/8 Cones, Medium Cut - (Prompt rebate on orders with 3 or more FreeShip items!)

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----> Go here to see all listings for vibratory media (ceramic, plastic, nut shells, polishing compound): <----
https://www.etsy.com/shop/NorthernWestStuff?ref=hdr_shop_menu&search_query=ceramic+vibratory+media
Note: This media is intended to be run in a vibratory finisher or some other high energy mass finishing machine. It will not perform well (unless you're very patient) in rotary tumblers. Although it will perform in rotary tumblers better than the ceramic media we have.

The specs for this plastic vibratory media:
Shape: Cones
Size: 3/8" (diameter and height)
Cut (aggressiveness): Medium Cut (M), ("General Purpose") - very common
Color: Blue
Please note that this is "new" media which I have never used. I assume that like ceramic media it will need to be "broken in", to expose the abrasive that's embedded in it. It was purchased at the same time as the ceramic media and I intended to use it in a low power, small vibratory finisher, but tried the ceramic media first which took up most of my time, so I never got around to using the plastic media.

This is the only plastic media we sell for vibratory finishing. It has never been used. It's a Rio Grande media, so it's oriented towards jewelry finishing: soft metals and small part sizes. It's made in China. Plastic media can cut faster than ceramic media, but not always. It can also do the opposite, cut lightly, and more gently than ceramic, but again, not always. Both plastic and ceramic media generally comes in many more shapes and cutting action (fast, slow, and polishing), so it's possible to use a ceramic media that "cuts lightly and more gently" like some plastic media.
Most of our vibratory media is ceramic. A lot of that has to do with economics, plastic media wears faster than ceramic (a side effect of that is it can cut faster than ceramic media, but 'not always'). Because of that it can be more expensive than ceramic media because you will get less cutting time with it before it wears down completely. The kind in this listing from Rio is cheap (until you add their shipping cost). There are enough ceramic media types to finish soft metals as well as plastic media, but perhaps not as fast.
Link to Rio blue cone plastic media product page:
{ https://www.riogrande.com/product/standard-plastic-cone-media-blue-medium-cut/339404gp }.
From Rio's description:
"-Smooths rough casting surfaces after the sprue is cut and filed.
-Very aggressive; produces good finishes.
- Workpieces can be painted or anodized after contact with this media."
Even with shipping it's a reasonable price because it's made in China.
Plastic media is generally used on soft metals. It is more often fast cutting or medium cutting. It's not good for polishing but it can leave a very smooth surface.

This plastic media was purchased several years ago (there's no shelf life, it stays "fresh" indefinitely). What we have is mostly ceramic media for an initial heavy cutting, then to medium cutting, then to polishing. We were trying to finish/polish small titanium "chunks" consisting of disks, rods, and irregularly shaped forged pieces. We also used it for rocks and minerals in sizes from 1 to 2 inches up to 8 inches in the same heavy cutting to polishing steps of the titanium.
Plastic media is just one type of media that can be used in a vibratory finisher. Ceramic media probably holds first place in media use if you include industrial usage. Other medias are exotic "ceramic" media made with higher temperatures, stainless steel and steel shaped media, hard nut shells (usually walnut) charged with a cutting or polishing compound, and corn cob or other soft media carriers. Simply do a google search on the phrase "plastic vibratory media" and you will come up with many suppliers and manufacturers of plastic, ceramic and other types of vibratory media, as well as educational info on the codes for ceramic types, and shapes ("ACT" = Angle Cut Triangles, "ACC" = Angle Cut Cylinders, "ACE" = Angle Cut Ellipse, etc.)
The titanium pieces we were finishing required some heavy duty media because of titanium's hardness and toughness. Most types of rocks we finished were igneous or metamorphic, harder and tougher than titanium. So, 90% of the media we have is ceramic media, and a lot of that is the heavy cutting "DF" media.

Here is a supplier who sells ceramic and plastic media and gives their code types with descriptions (unfortunately, code names vary from supplier to supplier):
http://vibratoryfinishers.com/tumblingmedia.htm
Here's another supplier who gives their slightly different code name types with descriptions:
https://vibrafinish.com/vibratory-tumbling-media/ceramic-media-descriptions/
Below is a good site for viewing photographs of actual media and doing visual comparisons. Click on "Tumbling Media" and the type of media you want to see. Of course these pictures are only of the media this particular company sells. The plastic and ceramic media from other manufacturers can have different code abbreviations and will look differently. And even the exact same media code from the same supplier can vary in color, because what they buy from their manufacturer depends on the materials the manufacturer has and how closely they stick to the same formula (quality control). Here is that link:
https://cmtopline.com/

The "cutting" action of plastic or ceramic media comes from the abrasive particles that are mixed throughout the plastic or ceramic matrix. There are several types of abrasives (aluminum oxide being the main one) and many formulations that vary by abrasive types and mesh sizes.
The variables in types of media are the composition and mesh size of the abrasive particles, the amount of abrasive particles in the plastic or ceramic matrix, the type and hardness of the matrix, the shape of the media, the size of the media, and the weight of the media (heavier media pieces cut faster).
Almost all ceramic media needs a "break-in" period when new. The abrasive particles are not yet exposed because the matrix is covering them on the outer surface. They need to be run with some loose abrasive grit, or some media which is already broken in. Or they can be run in a vibrator with no additives, just the new media rubbing and hitting against itself. The time it takes to expose the embedded abrasive particles varies with the type of media. Even "porcelain" ceramic media which has no abrasive particles needs a break-in period (to become shiny and "glazed" so it will polish).
What that break-in period causes is a certain time that's wasted; non-productive time (wear) on the vibratory machines. Even mixing new, non broken-in media mixed with used, broken-in media in a batch running parts will take more time to finish because only part of the media is cutting (the used media).
So, buying used media that's already "broken in" is actually more economical than buying new media because there's no need for a break-in period. There is no difference in the cutting action of the media as it wears down over time, except that it becomes smaller and it's true that media pieces that are larger are heavier and so hit the parts being finished harder, but you could also argue that in the progression of finishing, you want a smaller impact against the parts, you want a gentler cutting action as the finish becomes smoother. You will need to add more media to keep the mass in the bowl up to a certain height. On a weight basis alone, the cost of new vs used media is exactly the same.
There are a lot of variables in choosing the type of ceramic media at any one stage of finishing your parts. The main factor is the material the parts are made of and the size and shape of your parts. Are they all curves? Or do they have flat places? How large are your parts? Larger parts usually call for larger media size (for several reasons), but if you only have small media, it will do. It will just take a little more time to finish.
Another factor in choosing which media to use is the part final surface you want to achieve. It's pretty much common sense. If you want a high polish you will want to use a non-abrasive media or walnut shells charged with a very light cutting/polishing compound (and if the part surfaces start out rough, you'll first need to use 1 or 2 successively finer cutting medias). If you just need a smooth matte surface or if you just need to deburr, you may be able to use just 1 step (depending of the initial condition of the parts). If your "parts" are stone you will probably be wanting a high polish, which will require a sequence of the heaviest cutting media to start with. That will take the longest time and so you will need more of that media than the medium or light cutting media. If you're parts are a soft metal, like aluminum, silver, or gold, you'll need a milder cutting and finer abrasive media, something gentler and lighter weight. Walnut shells, again, may be a good choice.

Plastic and ceramic media is designed to run wet, with some exceptions (polishing can sometimes work well dry if the parts are close to a polished state). Running some types of low cutting medias dry is possible if you alternate dry with wet cycles. Running dry can cause a "glazed" (shiny) media surface. Glazing is only good when polishing (you want porcelain polishing media to be shiny; if not, it won't polish). Cutting action with glazed cutting media is nil. The cure is to run the cutting media alone, wet, and with some fine loose abrasive added.
Running plastic or ceramic cutting media dry that contains abrasive particles that cut part surfaces quickly, creates a fine waste byproduct consisting of metal from the parts and fine plastic or ceramic and abrasive particles. When running dry this will become compressed as a layer of grunge against either the parts, media, or both. It will "gunk" up the process until no further cutting is possible. The machine bowl must be run wet so the waste byproduct is mobilized as a loose slurry which doesn't appreciably slow further cutting. In a "closed" system the slurry will still eventually turn to slush, paste, and again, "gunk" up the process. That can be delayed by removing the lid and observing the movement inside the bowl. When it slows down, the addition of a little more water will extend the length of time the finishing process can continue. The goal will be to get the parts to a finished state before having to clean or "de-gunk" the bowl and media. After some experience you will be able to make judgements just by the change in sound of the media moving in the bowl, without having to remove the lid.
There are two main ways of dealing with waste in a wet process: a "closed system" approach, mentioned above, or a "flow-through" approach. Fairly self explanatory, the flow through system feeds a trickle of water (how much depends on the bowl size) through a fitting at the top side of the machine bowl and drains through a fitting on the bottom of the machine bowl.
The closed system approach relies on said observation of the media (visually or by sound). When the slurry is too thick there are several options. Dumping the batch into an external container and flushing it and the inside of the machine bowl clean is the most radical. Alternatives are several. What worked best for me was to make a "wand" of thin pipe with a nozzle to immerse in the machine bowl while it's running and thereby flow fresh water in with one hand. The other hand will hold a similar wand immersed in the bowl sucking slurry out with a pump. After a time, the thick slurry will be flushed out completely and replaced with clean water. Then more vibratory compound or whatever "soap" you like can be added to the water in the bowl ("just enough" water should be kept; a sign you have way too much is if any at all splashes upward around the center of the "donut" of the bowl).
The method chosen also depends on the size of the vibratory finisher, of course. My method worked great on my 17", 5 gallon finishers and less well on my 10", 3 qt finisher.
The method chosen for dealing with a wet system has side effects. The flow through system greatly discourages the use of vibratory cutting compound which is expensive. A flow through setup used with vibratory compound is like throwing money down the drain (almost literally in this case!). But vibratory compound really works. If you chose a closed wet system, it's use makes sense. About 1 part compound to 64 parts water is a typical ratio. A little vibratory compound added when the movement slows down works better than just a little water. Because of its expense people have tried all kinds of less expensive materials: Murphy's oil soap, borax, oxalic acid, dishwasher detergent+ammonia, etc. I've tried plenty of things myself. Some kind of soap fits the bill nicely, but whatever you use, it's most important to avoid creating foam in the bowl, which slows the cutting process.

Vibratory finishing has been around a long time now. An exact date is difficult to say but it probably began in the mid 1950's and took hold in the 1960's. It uses the same principles as rotary rock tumblers used by hobby rock collectors (popular with kids in the 50's, 60's, and onwards). The weight of the rocks constantly tumbling against each other with abrasive between them through successively finer abrasive stages for several weeks (or months) ended up with highly polished rock specimens.
Vibratory finishing is similar in that it rubs and hits parts together with an abrasive media under constant movement. But the difference is it does so with many times more speed and energy. Vibration is several orders of magnitude higher in energy than with a rotary tumbler. It can be adapted to very fast "cutting" for layers of oxide removal, to deburring, to simple smoothing, to high polishing. The strength of vibration can be varied with relative ease so that one machine can be put to multiple uses. It's used in industry for finishing large castings, or by jewelry makers for light smoothing and polishing of soft metals.

If your goal is heavy cutting you will be needing a fast cutting media. The variables for speed of cutting have been mentioned above. The total weight of the media pieces and parts matters. Of course the machine matters, too. The cutting speed is quite dependant on the energy (intensity of vibration) put out by the machine.
Weight is very important. If the media is heavy it impacts harder against the parts. The weight of the various plastic or ceramic media formulations can vary from 60 to 130 lbs per cubic foot. Usually though, there will be a range of weights listed for each type of media (size matters: larger media has more space between pieces than smaller media, so a cubic foot will weigh less for large shapes and heavier for smaller shapes). A particular formulation, for example, will be listed at a weight range of between 65 to 85 lbs/cu ft, or it may be between 90 to 120 lbs/cu ft, etc.
As mentioned above, the major abrasive used is aluminum oxide. The size of abrasive particles is usually in the 80 to 220 mesh range. Finer mesh sizes may be used for light cutting or pre-polishing. The coarser meshes will cut faster than the finer ones (the flip side of that is how smooth the resultant surface is; coarser meshes leave rougher surfaces).
The amount of abrasive in the plastic or ceramic matrix also has a great impact on how fast the media will cut. As the percentage of abrasive in a formulation increases so will the cutting speed, although a point is reached where it is no longer practical to increase the percentage due to low physical strength and friability of the media.

Aluminum oxide and alumina are chemically the same, Al2O3. But as mentioned above there are different kinds of aluminum oxide (or alumina). Porcelain is fired (or "calcined") white alumina, the stuff ceramists make dinnerware and industry makes toilets out of. Fused aluminum oxide is made by adding one more step by mixing it with a little iron in an electric arc furnace and taking it to very high temperatures. It comes out a brown/black color and is crushed to make tough (fused) "aluminum oxide" crushed abrasive particles. Porcelain (fired alumina) is too brittle to be used as an abrasive although technically it too, is still "aluminum oxide", although the word "alumina" is used to describe it.
For some applications, metal parts that have been finished by vibratory machines (or any other method) using a plastic or ceramic media that contains fused aluminum oxide can be "contaminated" by impregnation of particles of fused aluminum oxide that have been forced into the surface of a part. Metal parts made of titanium (which is inert and can be used inside a human body) that have small amounts of fused aluminum oxide particles exposed can cause compatibility problems with human tissue, since fused aluminum oxide is not inert. Other metals that have fused aluminum oxide contamination can cause other problems, for example if they are welded, brazed, or soldered at a contaminated area the joint will be much weaker.
Awareness of the possibility of fused aluminum oxide contamination for sensitive parts can lead to the choice of using a silicon carbide abrasive in the plastic or ceramic media. As mentioned above an "SC" (silicon carbide) ceramic media type exists (I haven't seen a plastic one, but one probably exists). Silicon carbide plastic or ceramic media does not have the contamination problem that fused aluminum oxide has. Blends of silicon carbide particles are used to get a media that cuts relatively fast but also leaves a very smooth surface. In general, if you look at a pile of pure silicon carbide abrasive particles, they will look black/dark gray with variable shininess. If you look at a pile of pure fused aluminum oxide abrasive particles, they will be a variably dark/darker brown. Silicon carbide is definitely a blackish material. Fused aluminum oxide (not the white kind) is definitely a dark brownish material. Silicon carbide is slightly harder (mohs 9.5) than fused aluminum oxide (mohs 9.0). Diamond, the hardest material, is mohs 10.

Usually, a part that has gone through an overall cutting process by aggressive heavy cut media, will require a second cutting with a milder media to achieve a smooth, scratch-free surface. This can be accomplished by using either an "MC" or "FC" (Medium Cut and Fast Cut) which, despite the names, I've found to be pretty close together in real world results. Both will achieve a smooth surface with the "FC" cutting somewhat faster than the "MC".
As your plastic or ceramic media wears down and becomes smaller, you will need a strategy for dealing with different sizes of the same media. Most people add more of the same media (some that's new and larger than the worn media) into the vibratory bowl with the smaller media. Sooner or later the smaller media becomes so small that it can become "lodged" (stuck) in holes/concavities in your parts.
At that point you will need to pour the media on a screen put over a bucket which allows the small pieces to fall into the bucket. What's left on top of the screen will be larger (but still smaller than new). If you have a "flow through" flushing system this method doesn't work quite as well because you're still keeping some of the smaller media and inevitably, some small pieces you missed will get into the liquid drain openings and clog your flow through set-up.
To be fair that's a universal problem with flow through systems; no matter what sizing method you use, the drain seems to inevitably get clogged with some stray small pieces (sure, screens and other measures can be taken, but seem to always fail, at least in less expensive machines). I was never successful at getting a long term flow through system to work reliably. If not watched regularly, when the drain would get plugged up, the water continues to flow into the bowl and floods it, stopping the cutting action and leaking water through any gaps in the lid/bowl. If you make sure to always use large, relatively new media in a flow through system, it has a better chance at succeeding. But even then media can sometimes contain a weakness and break into smaller parts and bam, there goes your "only large media" strategy and your finisher is vulnerable to getting plugged up once again.
Another strategy is to remove the media when it becomes a certain slightly smaller size and store it. If you finish different sized parts, you can then bring out the smaller media and use it for the smaller sized parts in a smaller sized machine. I've done this and kept about 3 or 4 step sizes of worn, smaller sized media. You have to collect enough of each size to have enough to fill the machine to a certain level, of course.

How full do you fill a vibratory finishing machine's bowl? Not all the way to the top is the generally correct answer. I've read that it should be anywhere from 1/2 full to 3/4 full. I think 5/8 (about 60%) is a happy medium. With vibratory machines, the first thing that usually goes bad (if you have a thick bowl that doesn't wear too thin too fast) is the bearings in the motor that has off-center weights on its shaft that create the vibrations. Those weights are how you adjust the intensity/energy of the vibration. Usually every machine will have a mechanism for moving those off-center weights towards the center, which decreases vibration and finishing speed, but increases motor/bearing life. If the weights are moved more off-center than where they were when the machine was purchased you'll increase vibratory energy but decrease motor/bearing life. If you're handy you can remove the motor and replace the worn bearings, getting more life out of your machine. Of course if you're not mechanically adept, you can also spend more money but less time, and just replace the whole motor.

Last but not least is Wikipedia, which I use so much. Their article on vibratory finishing, though, is short and very generalized:
{ https://en.wikipedia.org/wiki/Vibratory_finishing } :
"Vibratory Finishing
Vibratory finishing is a type of mass finishing manufacturing process used to deburr, radius, descale, burnish, clean, and brighten a large number of relatively small workpieces.
In this batch-type operation, specially shaped pellets of media and the workpieces are placed into the tub of a vibratory tumbler. The tub of the vibratory tumbler and all of its contents are then vibrated. The vibratory action causes the media to rub against the workpieces which yield the desired result. Depending on the application this can be either a dry or wet process.
Unlike rotary tumbling this process can finish internal features, such as holes. It is also quicker and quieter. The process is performed in an open tub so the operator can easily observe if the required finish has been obtained.
Vibratory tumblers have an action that is similar to filing. An eccentric, rotating weight shakes the tub in a circular path, during which the entire load is lifted up at an angle and then dropped. As the load is falling (but not actually airborne) the tub returns to an upward position, applying an upward and angular force that causes a shearing action where the parts and media rub against each other
Vibratory finishing systems tend to produce a smooth finish because the media essentially laps the parts. Since the load is moving as a unit, very fragile parts are quite safe in the vibrator. There is no tearing action or unequal forces that tend to bend and distort parts. The larger the parts or media are, the faster the cutting action.
The frequency and amplitude of the machine controls the finish of the parts. The frequencies can vary from 900 to 3600 cycles per minute..."
To get to plastic vibratory media, you have to go to Wikipedia's article on "Mass Finishing":
{ https://en.wikipedia.org/wiki/Mass_finishing } :
"Preformed resin-bonded media
Plastic or resin-bonded media utilize a wider range of abrasive types and sizes than preformed ceramics. The most popular grades are those using quartz as an abrasive. Aluminum oxide, silicon carbide and other abrasives are also used. Usually, low-cost polyester resins are employed as the binder and the various shapes are produced by casting. Resin bonded media is good for preparing a metal surface for plating.."-

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