Comparisons of Blender Jars with a Fixed Installed Blade to one with a Removable Blade Assembly August 12 2015
Blenders for the delicious smoothie concoction production are employed in restaurants, smoothie shops, or at home among many people in the world. These blenders come with different features, different sizes of containers, their blades / motors turning in either direction, sharp or dull blades / knives and various different designs of blade knife shapes. The issue discussed here is however the pros and cons of blenders and their jars with a removable or a fixed installed blade assembly.
A removable blade assembly is a blade cutting unit containing the knives connected to a shaft that connects to the blender gear. In between is a bearing that keeps the assembly turning smoothly without interruption. These bearings are a conglomerate of steel, usually carbide steel balls sealed up like also seen and used in roller blades. This sealed bearing unit is inside a housing along the shaft that is sealed from both ends in and outside of the jar to prevent water from leaking through either direction.
The blade assembly is inserted into the jar from the inside, sitting it into a hole on the bottom of the blender container. The blade assembly has a threaded area on the bottom. As inserted, from the outside a so-called nut or blade bottom plate, also known as a blade retaining nut (depending on who is the manufacturer), is then screwed onto the thread. This tightens and seals the blade assembly inside the jar to the container bottom and on the outside bottom. In between the bottom plate and the jar is a O-Ring gasket inserted that prevents water from entering.
Various styles of blades knives exist. Most companies use a 4 part or even a 6 part knife assembly where 4 to 6 knives protrude from the center shaft on top of the blender cutting assembly into different directions. Some of these ends point upwards 45 degrees, some are about horizontal, and others point down.
The blending results vary depending on the blade design together in connection with the layout and design of the blender container subject to specific interaction. The best type of blades are sharpened knives, sharp is better than dull.
These type of blades are usually made for jars that sit on blender motors which turn counter-clockwise. This is really for no scientific particular reason. At least some few smoothie and raw food gurus might claim there could be a cosmic harmony at play if the blender motor and the knife cutting assembly turn with the earth rotation, which is counter-clockwise. This may however at the minimum be really far-fetched from a credible reality.
Blender brands such as Vita-Mix, Waring, Hamilton Beach, JTC Omniblend, Omega, Kitchenaid, along that line, a few among many other blenders, have motors that turn counter-clockwise. In general, and usually, the more expensive upper-blender class has jars with very sturdy durable blade units that are screwed on from the outside of the blender container. The cheaper low-end blenders like Kitchenaid, Oster, Cusineart, and low end Hamilton Beach have much thinner units and also have to come off every time a jar needs washing.
Washing a jar with the blade installed or taken out should always be an option. Taking the blade out may also have the associated benefit to replace if the bearing might be worn out or simply has seized up due to age and wear and tear. It is just more sanitary if a user has the option and discretion to remove the whole blade assembly unit for cleaning, or for replacement if broken, or for sharpening or re-sharpening… any kind of maintenance.
Usually those companies that offer blender jars with removable or replaceable blade assembly cutting units, also offer a jar without blades by itself and the blade assembly by itself.
The bearings of these type of blades are prong usually to seize when over-exposed to water either through washing them in the dishwasher or soaking the jar and the blades inside the sink. It is possible that water could get into the bearing housing, although not likely or it won’t happen easily. It will happen over time due to wear and tear, and then the blade needs to be replaced, one of the advantages a removable blade – type blender container has over a container with a fixed installed blade, because that too tends to seize up.
As far as it is known, only Blendtec® offers a blender jar type with a fixed permanently installed blade. Instead of however equipped with ball bearings, these assemblies consist of bushings. A bushing is as opposed to balls (bearings) depending on a specific design, a buffer, a cushion type of two ends that are greased up and rub against each other in a manner that little friction arises, as little as possible.
In the cases of the Blendtec Jars, either Wildside®, the Fourside®, or the Twister® Jar, Blendtec uses such a bushing instead of ball bearings. This allows for a much smaller housing around the shaft that must stay lubricated to easily turn and follow the torque forced onto the dual wing-tipped blade assembly. By the way, Blendtec blades are not sharp.
The advantage of a bushing is that is uses up less space than the ball bearings in a housing and therefore can be installed closer to the motor gear, of course in respect to other blenders, that being really minimal. The disadvantage is that bushings are usually not as strong and durable as ball bearings.
Water still can get into the though hermetically sealed off blade shaft bushing housing, especially and controversially associated to the lack of usage. Water and usage usually keeps and helps to keep the bushing seal area lubricated and seal. If it dries out too long especially after usage it can often happen that the seal separates and the bushing seizes up and you can’t no longer use the container .
These types of bushing-operated blender blades are not replaceable. Sure they are removable and replaceable if one had the tools to remove them and put them back in once cleaned up and repaired. Consumers, especially however restaurant shop and smoothie shop operators tend to move away from fixed blade blender jars because of the cost factor. They have to replace the whole jar, which is still good and usable, however just because removable blade features are not available.
Other advantages of have a blender jar with the option to remove and replace blades is not just for the purpose of repair and maintenance, but also for opening the door to use and facilitate different styles of blades. Of course a controversy exists that one blade may do it all. But it has been proven, although in general it is true that even a dry blade can blend up wet ingredients, a wet blade also blends very effectively dry grain wheat ingredients and coffee, and ice too can be blended with any of the various blade and knife design setups, that differences and high efficiency outcomes vary subject to blade design. A smoothie shop that makes one kind of an ice type smoothie may over time help to save energy and even prolong the life of the jar and the blades all together as opposed to using a more generic blade assembly unit.
As introduced up on top, blending is done with much variable consideration to the design of the jar, the blades, and the sharpness, as well as the power of the motor, and believe it or not, also of how the ingredients are placed inside a jar, in which order, if hard solid frozen or fresh soft is on top or bottom. Even the use of a tamper adds to the variable of blending effectiveness.
Tampers are mostly only used when the consistency of the ingredients is more solid than liquid – it’s a liquid to solids ratio issue in most cases. As long as the blender unit can turn and create a vortex, the action in which the blades propel all ingredients in a turning action and creating a liquefying emulsifying texture of the ingredients, no tamper is needed. Getting stuck, especially when making intentionally solids purees or paste, even nut butters, some kind of a stir stick, aka plunger (ouch – not toilet related) can just give the push to get that vortex going or to stir the puree into a fine creamy concoction.
Sharper blades can cut better. That is definitely demystified. No way that dull knifes are better than sharp knives. The consumer and commercial smoothie market will soon see the Blendtec blender industry with sharpened knives. As a matter of fact, a company called Alterna jars already has come out with sharpened knives, they are also removable and replaceable, of course. The Alterna jar is made to fit on the Blendtec blenders, as well as with a simple blade assembly switch, will fit also on those blenders that turn counter-clockwise.