The Cleaning Process

Discussion in 'Design and Modeling' started by theraincost, Mar 12, 2013.

  1. theraincost
    theraincost Member
    Hello,

    I have recently had a my first few creations fail because of insufficient escape holes and and inability to clean. Can anyone shed any light on the cleaning process so I can make the relevant changes?

    some more detail:

    One of my models is a standing low poly wolf and he has 4 legs each around 4mm in diameter. Is a 2mm tunnel up each leg leading to the interior cavity enough to clean out waste material. Each leg is around 60mm long



     
  2. stop4stuff
    stop4stuff Well-Known Member
    There's a video here that shows the print and cleaning process. Basically an operator needs to be able to blow the support powder out using an air jet.

    2mm tubes up the legs of your wolf should be ouk, but you may find some support material still in the model depending on how diligent the cleaning operator is.

    Paul
     
  3. theraincost
    theraincost Member
    Thanks for the link.

    That has answered my question perfectly.

    Fingers crossed my new versions make the grade.

    Thank you for the rapid response.
     
  4. NickHawkins
    NickHawkins Active Member
    I've recently had a (1/200 scale aircraft) model in WSF rejected for the same reason, the same model had been printed without comment before.

    Having watched the video I can't believe that models are now being rejected because Shapeways can't recover the unfused powder from the inside of a small model. It was clear that much more powder was blown around the workshop (and not into the collectors) during the rough cleaning process than could be recovered from the inside of a small model.

    Can anyone confirm if Shapeways are now enforcing the cleaning hole requirement for small WSF models to the letter?

    If so I will need to redesign several models to avoid disappointment for future customers (as I suspect many other designs will).
     
  5. Youknowwho4eva
    Youknowwho4eva Well-Known Member
    Unfortunately, for some rules, it's up to the reviewers discretion. Cleaning is less for reclaiming material, and more so we aren't shipping powdery models to customers.
     
  6. NickHawkins
    NickHawkins Active Member
    Thanks for the clarification.
    Sadly that means as a designer I have to allow for "worst case" reviewers, it seems to be a rather stochastic process.

    From my current experience of WSF it seems that anything trapped inside after shipping normally stays there unless you drill holes in the model (EG for mounting on a flight stand). Once painted there's normally no way anymore powder can get out.
     
  7. Youknowwho4eva
    Youknowwho4eva Well-Known Member
    A solution for variations in rejections is in the works.

    The problem with the left over powder, isn't so much for people that are expecting the powder. If a customer bought the item expecting a final product, and powder come out, there is a chance they wouldn't be happy, and could reflect negatively in there future shopping choices.
     
  8. NickHawkins
    NickHawkins Active Member
    My first rejection was because the hole was tiny, just enough to ensure the model was marked as hollow and I suspect was completely sealed by the fusing process. So I made it bigger...

    Would it be possible to have a standard for strong flexible that either requires either the large cleanable holes OR a tiny hole that will be sealed by the fusing process? Either way the customer gets a model with no dust (unless they cut it open).
     
  9. Youknowwho4eva
    Youknowwho4eva Well-Known Member
    I know that is an option for FD and FUD. But the support for those materials is not reusable.

    Just wondering, how small is your hollow area? Is it needed? I know any amount of material can save money, but it sounds as if your hollow area is very small?
     
  10. NickHawkins
    NickHawkins Active Member
    I'm designing 'toys' for wargamer's rather than precision scale models for collectors, as such there is a 'market expectation' regarding price that I try to meet.
    These are also models that may be used on fairly tall flight stands so minimising weight is of practical benefit.

    The biggest saving I have achieved is a 14cm3 model that only requires 3.5cm3 of material, this is exceptional. I'd guess that typical savings are 25% to 33%, a useful saving for something that is intended to be ordered in multiples rather than singles and as part of a multi-model order.