Why not rubber instead of Delrin small parts ?

MarkInLA Oct 29, 2016

  1. MarkInLA

    MarkInLA Permanently dispatched

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    Hi. I have this cell phone charger. The wire from it to its tiny plug is some kind of rubber that is so resilient and tough it is near impossible to even wind into a coil to put it away. Near everything I try, it finds a way to unravel itself and return to being straight. I've never seen a substance like this !! It's as if it has a memory.. Recently this got me to thinking: Lots of us have had tiny parts (brake rigging, turnbuckles, linkage, stirrups, bell supports, roof top horizontal hand brake wheels, and other tiny parts (HO for me) brake off (mostly on steam). I had a Bachmann ten wheeler I broke things off of under the cab..Yes they are usually delrin, which is the industry standard for the most part..But it still can snap in two as we've so sadly experienced..
    Would it not be feasible to make these same parts from this same rubber as my charger's ? If they were, I believe they would bend but very rarely snap off, and would of course return to original shape... Anyone know what this substance on my charger wire is called ?. Again, it's not common rubber like a car tire or pencil eraser. It's really stubborn, dense, flat black, and very smooth, but not slick like delrin ... M
     
  2. acptulsa

    acptulsa TrainBoard Member

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    Rubber tends not to hold its shape as well, particularly if it's thin and freestanding (or hanging) like a brakewheel or a stirrup. It does not support its own weight well. It is susceptible to heat (unless it's formulated to withstand it like radiator hoses and tires, which compounds tend to be very porous and rough to the touch).

    You have an interesting idea. But the substance coating, for example, cell phone plugs is coating metal and/or plastic, and really does need that to have any definite shape and maintain it. Use it to coat a wire stirrup and it will stay that shape; mold a stirrup out of it and its first exposure to sunlight is liable to turn it into a pretzel.
     
  3. Hytec

    Hytec TrainBoard Member

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    Raw material cost and processing complexity may be factors. I've no idea of the cost difference of hard rubber and delrin, but years ago I was told that an automobile manufacturing employee was given a cash award if he could save a penny with the purchase of each bolt, nut, or washer. With processing, I wonder if you can get the same details with rubber as with delrin. Also how long does it take to mold and cure the two materials? A difference of an hour would raise labor cost, and increase the time that the molds are not available for the next run. Maybe one of our members who is in the manufacturing business, like Paul Graf, could give some insight.
     
  4. ken G Price

    ken G Price TrainBoard Member

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    Unlike almost all items sold for model rail roading when used on a mass produced, consumer item that sells in the tens of millions,
    this is an inexpensive, cost effective product.
    For sales under 100,000 not so much.
     
  5. MarkInLA

    MarkInLA Permanently dispatched

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    KEN, not understanding your reply. Are you saying my idea for the rubber pieces would not be expensive to convert too ? Maybe the kind of rubber I sited would work fine in the original (say brake linkage) molds. I'd be so nice to no longer fearing we'll break a small part off while say rerailing a loco or car. Accessories such as telephone/telegraph poles could bend if we are reaching into a scene for something else..Again, I'd like to know just what kind of rubber it is on my charger cord. It's very Very resilient; not like rubber-band rubber...M
     
  6. Hytec

    Hytec TrainBoard Member

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    Mark, I believe Ken was referring to the economics of volume. High design and manufacturing start-up costs spread over over ten million units become insignificant. But when you can only spread those same costs over model locomotives consisting of a thousand units, those costs become a significant portion of the model's per-unit cost, possibly pricing it out of reach for most modelers.
     
  7. MarkInLA

    MarkInLA Permanently dispatched

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    Thanks. Whatever the economics of it are to switch to rubber parts doesn't matter to me. Never say never. I'm just asking hypothetically, if it could be done, doesn't it make sense; to have tiny parts bend, then regain their shape instead of snapping off. Whatever this rubbery material is on my charger cord, it's almost rebellious !...I mean it ! It's very Very hard to raval up.. It tries to unwind from any coil you try to make...Any !! ...M
     

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