TOS Enterprise question????

Discussion in 'Studio Scale Models' started by DarthJRW, Jul 23, 2005.

  1. DarthJRW

    DarthJRW Well-Known Member

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    hey guys

    im making a 3 foot vaccumformed model of the TOS enterprise.

    now ive got all the parts covered EXCEPT the saucer.

    could someone give some tips on how to make the saucer,like what material to make the mold out of ???

    thanks

    DarthJRW
     
  2. jakob2121

    jakob2121 Well-Known Member

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    seems like MDF would be the way to go.
     
  3. DarthJRW

    DarthJRW Well-Known Member

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    ya but with all the little dips and curves how would go about shaping it ??
     
  4. jonnytrooper

    jonnytrooper Well-Known Member

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    Hey, if you need any help, I can stop by sometime this week. Did you ever cast them in resin, or did you decide to vacuform the little greeblies?
     
  5. DarthJRW

    DarthJRW Well-Known Member

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    hey jonny

    the little greebles will be cast resin but i still cant find a way to get the saucer done

     
  6. phase pistol

    phase pistol Master Member RPF PREMIUM MEMBER

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    Well you'd have to turn a disc of wood on a lathe I guess?

    The saucer is symmetrical except for the teardrop shaped B/C deck on top...

    [​IMG]

    - k
     
  7. jonnytrooper

    jonnytrooper Well-Known Member

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    Reporting for duty sir, when should I come over. Hows tomorow?
     
  8. DarthJRW

    DarthJRW Well-Known Member

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    pm sent :D









     
  9. jonnytrooper

    jonnytrooper Well-Known Member

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    I'll talk to you tonight or tomorow then. Just sitting down to watch lotr, talk to you later

    -JT
     
  10. DarthJRW

    DarthJRW Well-Known Member

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    any other suggestions????
     
  11. jakob2121

    jakob2121 Well-Known Member

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    MDF would be easy, though you'd have to hand-shape it with a plane. Heck, you could make "steps" of various diameters and bondo the slope between 'em.
     
  12. star-art

    star-art Sr Member

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    Well, without trying to reinvent the wheel, there are basically three approaches that have been done in the past:

    1. Turn a very large disc out of Renshape or other wood substitute. Requires very expensive special equipment, limited by the size of dish needed.

    2. Make radial ribs, fill in with foam, then sand to shape. Difficult to get a perfectly even surface this way, but you can work in any size.

    3. Build a custom rig and turn the shape from hydrocal. This is what Custom Replicas did with their big 5.5-foot model. It works. And hydrocal should make a good master for vacu-forming -- just watch out for shrinkage. You might try to avoid making the plaster too thick so it won't crack or shrink. Place it on a strong backer board as well that won't flex under pressure and allow it to crack.
     
  13. DarthJRW

    DarthJRW Well-Known Member

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    how would i go about making the rig????



     
  14. star-art

    star-art Sr Member

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    Unfortunately I see the photo is no longer on their website. You start with a flat surface such as a table, in the center is a rod or tube. Over this mounts a scribing template which is a piece of rigid sheet metal in the shape of 1/2 of the hull profile. You would build up the center area with scraps or whatever to make the final plaster surface an even thickness.

    Apply the plaster when it is the consistency of whipped cream, then rotate the scribing tool in a circle to shape the plaster. This is tricky and requires some practice. Shape the plaster as much as possible before it is fully hardened. Keep building up layers until you are done, keeping in mind that additional layers will cure more quickly because the underlying layers will absorb the water from the new material as soon as you apply it.

    Be sure to use only high quality hydrocal plaster.

    If your finished model is 1/350 then the saucer won't be that big, so the very best approach is probably turning a master from Renshape if you can get access to a lathe that can turn bowls and dishes that large.

    Hope that helps.
     
  15. DarthJRW

    DarthJRW Well-Known Member

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    whats renshape?
     
  16. CaptCBoard

    CaptCBoard Well-Known Member

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    Renshape is one of a family of mastering materials intended to replace wood and aluminum, made of a filled urethane it comes in various thicknesses and densities. Model Plank, from BJB is a similar product but not as expensive as RenShape. That being said...

    I really hate to say this, but if you don't know about the plaster technique and you don't know what RenShape is, you probably don't have enough expertise to pull the job off without a whopping huge amount of experimentation. My recommendation is to find someone who already knows how these parts should be made and have them do the mastering. And second to that suggestion is, in the case of this particular part, you should definitely NOT be trying to vacuform over a postive master, but pulling the plastic into a negative. Getting the pull out of the negative will not only be much easier (basically it'll just jump out) but if you put any detail on the 'positive', it will come out much crisper since the finished surface of the plastic will have been against the finished surface of the mold. Pulling plastic over the positive itself means the contacting surface is on the inside and any detail will be 'mushed' due to the thickness of the plastic (even if its really thin...). Even if there isn't any detail being formed other than the general shape, its still better from a production standpoint to pull the plastic into a negative mold-- the parts will be very easy to remove and the mold will hold up much longer as there are no shrinkage stresses building up on it. If you are only making a few (less than 5 or 6) of these parts, it probably won't matter. But if this is going to be a kit where you make more than that, this is a consideration you need to be aware of.

    Scott
    CaptCBoard@AOL.com
     
  17. cobywan

    cobywan Sr Member

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    Smooth on sells resins that are specifically created for making vacuumfoming molds.
     
  18. DarthJRW

    DarthJRW Well-Known Member

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