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    #16
    What's your definition of a "cantilevered wheelchair frame"?

    Cantilever is when a beam is anchored on one end allowing it to overhang or suspend on the other without support. On a wheelchair, one end is supported by the casters while the other end is supported by the rear wheels. Both ends of the frame are supported and, therefore, no cantilever.

    This would be a cantilevered frame:

    See how the back of the frame has no support?


    This is not:



    See how it has support/anchor points on BOTH ends of the frame?
    Now if we're talking about the frame only, it's still not cantilevered because if you take the rear wheels off, the back will fall to the ground and, as a result, be supported by the ground. Still two anchor points on both ends of the frame:




    What am I missing? Why am I confused? Is 'cantilevered' a word that the chair companies used or was it a started by a user who doesn't understand? Or is it me?
    Last edited by brian; 6 Apr 2012, 11:41 AM.

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      #17
      Originally posted by brian View Post
      Does anyone know how or why the word "cantilever" ever became used to describe L-frame chairs? It's a pet peeve of mine.
      I call them L frames because that is what they are, looks like a L but in different position.
      The backrest if is not welded to the frame is not part of it imo.

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        #18
        Originally posted by totoL1 View Post
        I call them L frames because that is what they are, looks like a L but in different position.
        The backrest if is not welded to the frame is not part of it imo.
        i agree L frame would've made more sense, but "L Frame" was already taken by Oakley, so they couldn't use it?

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          #19
          I'm not sure, I was a philosophy, sociology, and linguistics student. Never took any engineering courses.

          I've never heard the term 'cantilever' in reference to anything other than the frame, is all. Your, quite literal and I'm sure 100% technically accurate, explanation includes the wheels.

          For the sake of clarity, using your explanation, it seems to me the term refers to removal of the lower frame bar (ignoring everything but the frame...i.e. backrest, wheels, forks, etc) and the effect that had on the frame design, going from a closed box to an open L, with the only other frame support for the top frame rail coming from the vertical front frame rail.

          Sure, add the rear wheels and you're back to a box.

          Fwiw, even is we include the wheels, a cantilever, according to the limits of my knowledge...which is your post and Wikipedia...can, in fact, be supported by 2 vertical sections (like the front and rear wheels) as long as there is some overhang at one end. Like a diving board.

          Does this make any type of fully assembled wheelchair with the rear axle located anywhere forward of the rear end of the seat tubes a type of cantilevered design?





          Originally posted by brian View Post
          What's your definition of a "cantilevered wheelchair frame"?

          Cantilever is when a beam is anchored on one end allowing it to overhang or suspend on the other without support. On a wheelchair, one end is supported by the casters while the other end is supported by the rear wheels. Both ends of the frame are supported and, therefore, no cantilever.

          This would be a cantilevered frame:
          [ATTACH]44412[/ATTACH]
          See how the back of the frame has no support?


          This is not:
          [ATTACH]44413[/ATTACH]


          See how it has support/anchor points on BOTH ends of the frame?
          Now if we're talking about the frame only, it's still not cantilevered because if you take the rear wheels off, the back will fall to the ground and, as a result, be supported by the ground. Still two anchor points on both ends of the frame:

          [ATTACH]44414[/ATTACH]


          What am I missing? Why am I confused? Is 'cantilevered' a word that the chair companies used or was it a started by a user who doesn't understand? Or is it me?
          "I have great faith in fools; self-confidence my friends call it." - Edgar Allen Poe

          "If you only know your side of an issue, you know nothing." -John Stuart Mill, On Liberty

          Comment


            #20
            Originally posted by jschism View Post
            i agree L frame would've made more sense, but "L Frame" was already taken by Oakley, so they couldn't use it?
            Except that wheelchair manufacturers wouldn't be using "L-Frame" as a model or brand name, only as a descriptor. You can't sue over that (or, at least, it would be very difficult).


            Originally posted by DaleB View Post
            I've never heard the term 'cantilever' in reference to anything other than the frame, is all. Your, quite literal and I'm sure 100% technically accurate, explanation includes the wheels.
            BUT as my final (and masterful) illustration indicates, take away the wheels and the frame would collapse. At that point the frame is again being supported by two points on either end. It becomes something different.

            Originally posted by DaleB View Post
            a cantilever can, in fact, be supported by 2 vertical sections as long as there is some overhang at one end.

            Does this make any type of fully assembled wheelchair with the rear axle located anywhere forward of the rear end of the seat tubes a type of cantilevered design?
            Yeesh. Maybe. But that, as you suggest, would mean that a whole host of other chairs would be considered cantilevered and would not be specific to this L shaped design. So if you use that to plug the hole in this argument, it opens up 5 others.

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              #21
              Is it just me, or does the last pic symbolize that ..

              open frame = cantilevered frame

              is an argument that falls flat on its face?
              Last edited by SCI_OTR; 6 Apr 2012, 1:50 PM.

              Comment


                #22
                Originally posted by brian View Post
                Yeesh. Maybe. But that, as you suggest, would mean that a whole host of other chairs would be considered cantilevered and would not be specific to this L shaped design. So if you use that to plug the hole in this argument, it opens up 5 others.

                Ugh. I see your point. Maybe it would be easier to add a new definition to the term 'cantilever', since it's become common vernacular, than to try to fit it into one of the existing definitions. Language evolves like this, all the time! One of the things about it I like so much.

                You see it through engineering, equally fascinating in it's sphere, I see it through people, and language.

                Pretty cool, I think!



                I'm curious about who and when the term first was applied, too, and what their reasoning (and personal lens) was.
                "I have great faith in fools; self-confidence my friends call it." - Edgar Allen Poe

                "If you only know your side of an issue, you know nothing." -John Stuart Mill, On Liberty

                Comment


                  #23
                  Wow! This thread took a hard left in a scientific kinda way. LOL
                  SCI Birthday: April 25, 1993
                  T4,5,6 Incomplete
                  Chair: TiLite TR3

                  Comment


                    #24
                    Originally posted by wheelin 48 View Post
                    i have a zra is the tr any harder getting in the car
                    have you tried putting in your ZRA in vehicle with the back up and side guards on(if you have them)? if you can do that, the box frame wouldn't be any different.
                    There, now the thread is back on track!

                    Comment


                      #25
                      Originally posted by jschism View Post
                      There, now the thread is back on track!
                      ..and you would describe your Icon as having a __________ frame design?

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                        #26
                        Originally posted by SCI_OTR View Post
                        ..and you would describe your Icon as having a __________ frame design?
                        a great new frame design

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                          #27
                          I use to fold the back down and lay me ZR upside down in the backseat with the wheels on the floor. fit perfect and the wheels against the front frame kept the chair from moving around and flipping over while driving. Still works with the Icon, but the folding back is pretty much useless with fixed fendered sides.

                          Comment


                            #28
                            Originally posted by jschism View Post
                            There, now the thread is back on track!
                            No, no, let me derail it again. I love the argument over semantics.

                            While we're at it, can we quit referring to dealers/vendors as DMEs?

                            DME = durable medical equipment.



                            Originally posted by jschism View Post
                            Still works with the Icon, but the folding back is pretty much useless with fixed fendered sides.
                            What back are you using? The fixed sideguards shouldn't get in the way of the back folding.

                            Comment


                              #29
                              I'm super literal and also wondered why they were called cantilever. Now, what do you guys think about them being called Z frames?
                              Board Member of Assistance Dog Advocacy Project working in Education. Feel free to ask me any service dog questions!

                              I am not paralyzed. I have a genetic connective tissue disorder with neuro complications and a movement disorder.

                              Comment


                                #30
                                Originally posted by -scott- View Post
                                No, no, let me derail it again. I love the argument over semantics.

                                While we're at it, can we quit referring to dealers/vendors as DMEs?

                                DME = durable medical equipment.





                                What back are you using? The fixed sideguards shouldn't get in the way of the back folding.
                                The side guards don't get in the way. I have a 10"tall ADI CF back, folding it doesn't give me much of a gain. plus with no rigidizer, it was too hard to grab with the back folded when putting it in my SUV. It didn't take long to get use to loading with the back up and side guards on, I would've swore I couldn't have done it back when I was still using my ZR.

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