Mold-making/Resin-casting with a Shapeways model...

Discussion in 'Finishing Techniques' started by magengar, Jan 15, 2013.

  1. magengar
    magengar New Member
    Hi everyone, I'm new at this hobby. I'll start having some of my own objects printed soon.
    I want to try the White Strong Flexible material (WSF) for my mold-making/resin-casting projects.

    My question is:
    Will the white-strong-flexible material printed model hold up well inside
    a silicone rubber mold as the mold cures?

    (Before I begin the mold-making process I must coat the original object with
    a mold Release Agent. The Release Agent will prevent the silicone from sticking
    to the original object, thus making it easier to remove the object after the
    silicone rubber mold has cured.
    I'm worried about the possibilities of the Shapeways object getting damaged
    from the chemicals in the silicone rubber while the mold is curing.
    The mold takes about 18 hours to cure... I usually let it cure for 24 hours maximum
    before I remove the object from the mold.
    For reference, I'm using the Alumilite silicone rubber mold-making kit.
    )

    High Strength 3.jpg

    Thanks in advance. :)
     
  2. stonysmith
    stonysmith Well-Known Member Moderator
    Simply put, WSF is nothing more than Nylon. I might be totally off base, but I can't imagine that the 'rubber chemicals' will do any damage at all to the nylon, especially given that you're going to be coating the nylon with the release agent.

    If you want to test it, go find a nylon coat hanger and try casting a section of it.

    The one thing you need to consider is that the printing process produces a porus matrix, rather than solid. It will suck up quite a bit of the release agent, but that shouldn't hurt what you're trying to accomplish.
     
  3. magengar
    magengar New Member
    Thank you, Sir! I'll give that a shot before I go ahead with an object from Shapeways.
    I noticed some of the WSF materials seem rough-textured... I shouldn't have any
    problem lightly sanding the surface smooth and perhaps sealing the surface
    with a coat of acrylic so that the silicone won't get absorbed into the object.
    I know that once I get my first object printed at Shapeways I'll become addicted! :D

    Again, Thank you! :D
     
  4. sherman
    sherman New Member
    i have been making moulds of models since 1985 and have moulded all sorts of things.
    i have now started to mould 3d printed models as well in the white nylon.
    it will be ok in a silicone mould as there is no presure but thin pieces may break off when demoulding it.
    i have also vulcanised some white nylon in a vulcaniser as 90 degc and 10 tons of presure but these were solid parts and it had no detrimental effect at all.
    you will not be able to sand down the 3d print to make it smooth however esp in areas of detail.
    i make a mould then a cast and then modify that cast instead, costs more in moulds but it is worth it in the end.
    good luck with it, it is a steep learning curve.
     
    Last edited: Jan 18, 2013
  5. magengar
    magengar New Member
    Thanks guys... I welcome tips and suggestions,
    they're all helpful.

    Casting from the Shapeways-printed object and
    then modifying the resin copy is a good idea.
    I usually end up modifying and touching up my
    first resin cast object, anyway.
    I can just use the Shapeways object as a template
    to start the basic sculpt for things I'd otherwise find
    impossible to sculpt from scratch with clays and putties.

    As a hobby, I collect Japanese action figures and model kits
    of anime robots from the '70s and '80s anime tv shows...
    ...some of my robot figures may need replacement parts,
    or I'd customize some of my beat-up robots with my own
    custom-made parts.
    Then there's just the one occasion in which I don't wanna
    modify a newly-bought robot figure, but I'll cast its body parts
    to make a resin copy of the robot figure, or, I'd use the parts
    to make enemy robots for the hero robot figure. lol :D

    McMAZ_final01.png
     
  6. sherman
    sherman New Member
    good luck with ti, if you need any advice on moulding ect please email me
    sales@sandsmodels.com
    see my stuff on
    www.sandsmodels.com
    thanks
    shaun