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Thread: How to keep a moving plate level

  1. #21
    Project Engineer
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    Ah, I did not know that.
    Thanks.


    Btw, http://www.merriam-webster.com/dictionary/squoosh says "squoosh" has been is use since 1942.

  2. #22
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    Quote Originally Posted by dalecyr View Post
    Btw, "squoosh" has been is use since 1942.
    Good to know, thanks, but I only use the Unabridged Oxford.
    No exact results found for "squoosh" in the dictionary.
    Did you mean scoosh?
    Did you mean skoosh?
    Did you mean squash?
    Did you mean squish?
    Did you mean sloosh?

    Besides, my understanding of the word, is derived from Smoosh and Squash.

  3. #23
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    How much would it squoosh?
    Just a skosh?

  4. #24
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    As promised, here is a picture of the completed press.
    downsized_1116111907.jpg

    This shows the frame, guide rods and the 12 ton air over hydraulic bottle jack.
    Additionally, the all aluminum 40 count punch/die set is sitting on the moving platen.

    A "substance" is poured into the die part, the punch is aligned with the die,
    and the press does it's work, making 40 half inch tall by half inch diameter pellets.

    Those pellets are used in a larger "assembly",
    which eventually is propelled at a very high speed
    into the air a thousand feet or so.

    A chain reaction is initiated, resulting in the rapid expansion of the assembly,
    while simultaneously raising the external temperature of the aforementioned pellets,
    producing the effect pictured below.
    fireworks2.jpg

    By the way... there is a staggering number of costly licenses required to do this legally.
    And I have ALL of them.

  5. #25
    Technical Fellow jboggs's Avatar
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    Have you looked at DU or DX bushings from GGB (Garlock)? I've used them successfully in many applications. The thin plastic coating doesn't "extrude", and the steel backing makes it stiff. They're pretty thin though and aren't meant to extend beyond the housing bore.

    I'm still concerned about how much off-center loading your system will tolerate without binding or damage. In my experience die sets are used in presses in which the forcing mechanism is self-aligning, preventing any angular misalignment. You don't have that. But other folks have other experience, so we'll see. Nothing beats a live test

  6. #26
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    I added some UHMW to each side rail,
    and added a steel side to the moving platen,
    which slides on the UHMW.

    This was because tests showed that off-center loading was definately a problem.

    Seems to work fine now,
    although I have not tried a load placed at, oh, say, 2 inches from the left side.

    But the "design spec" called for only center loading.
    And those of us who will use it, know that.

    It does the job it was designed to do.
    Even so, I am not very happy with the execution of the design.

    It does not have that "quality piece of machinery" feel to it.
    And I do not know why, or how to fix it.

  7. #27
    Technical Fellow jboggs's Avatar
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    Paint it! That always works around here.
    Or maybe surround it in a nice 8020 frame with smoky panels.
    Don't forget the flashing light on top.
    And definitely add a knob or two so the operator can adjust something, anything.
    Hey - how about touchscreen controls?!?!

    If it works it looks great.

  8. #28
    Lead Engineer RWOLFEJR's Avatar
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    Curious about a couple things...
    How sturdy are the pellets after squooshing them? How long do they need to be held at some certain pressure? How easily do they come out of the holes? How many of these are you going to make? Are you pulling the mold pieces out each cycle and poking the peckers through to strip them out?

    Reason I ask all that is cause I'm wondering if ... depending on quantities... add a second plate and second cylinder. Then fix your mold parts along with a solid plate to act as a floor for the initial filling... press then let floor fall out and peckers poke the pellets out on continuation of upper cylinder stroke. Maybe tip the assembly so they fall into a chute and into a bucket etc.
    Lower moving plate would be the solid plate running up to a fixed plate with your cavities. (fixed plate is a plate with through holes) The solid lower plate smacks up to the fixed plate with holes tight and you fill your holes. (If at an angle then the depth of hole would need to accomodate the aangle of the dangle...) Then the upper cylinder lowers the peckers into the cavities. It has less presure than the lower plate so it won't overcome it. After pressed you lower the solid bottom plate and in doing so the pressure of the upper plate pokes the pellets out. (peckers are longer than the holes...) If at an angle they fall into a chute etc...

    Iff quantities are there... I'd replace the bottle jack with some nice cylinders and a tank and pump set. Variable dsplacement vane pump and a couple pressure switches... couple checks... maybe a timer... a few gages and Voila!

  9. #29
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    Hi Bob.
    The pellets are pretty stable; one can not crush them with one's fingers.
    Or at least not very easily.

    The press is held at maximum pressure (about 24,000 pounds) for about 5 seconds.
    The compound is wet when pressed.
    The punch/die sets are constructed such that water is allowed to flow out,
    while restricting the larger compound grains.

    The picture is a little deceptive; the punch/die set is upside down when in use.
    I am in fact pressing the compacted pellets out very similiar to what you suggest.

    The punch sits on the moving platen, and a spacer is placed between the punch and the die.
    This allows us to pour in (fill) the die with the compound to the top of the die,
    and gives us a pre-measured amount.
    The variances in volume are not critical in this application.

    The spacer is removed, the press is actuated, compacting the compound between the punch(es)
    and the fixed top plate. Pressure is held for 5 seconds or so, relaxed an inch or so, and the spacer
    is moved to above the die.
    Light pressure is applied, and the pellets easily press out the top of the die.
    The punches are .5" longer (taller?) than the die.

    We can make about 400 pellets an hour using this method.
    A 12" diameter "assembly" will use up to 600 hundred pellets.

    I have made other punch/die sets for other sizes and configurations.

    The production quantity is essentially limited by the number of punch/die sets.
    The highest count one I have built is a "40 up", which is shown in the picture.
    Tolerances are fairly tight; the 40-up punch can be inserted in the die in any configuration.
    (meaning, the punch can be rotated 180 and still fit.
    Or just the die can be flipped vertically and it all still fits/works.)
    The largest diameter one I have built is 3".

    It produces enough for our needs.

    TouchScreen controls... ya know... I could do that...

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