Stainless Steel Thin Sections Suggestions?

Discussion in 'My Work In Progress' started by tunabreath, Feb 7, 2013.

  1. tunabreath
    tunabreath Member
    I have a part here which has been deemed unprintable and I'd like some suggestions on the simplest (and least expensive, volume-wise) way to make it printable.

    Attached is an image of the feature in question, a camming groove. The backing material to keep the cam from slipping off is very thin. Would adding one or two evenly spaced ribs on the back side of the groove to support the material be sufficient? (bring thickness up at the ribs to 1.5-3mm), or will I have to increase the thickness of the whole part in that section? (will have to be ground off later, the total thickness of the part is controlled)
     

    Attached Files:

  2. bartv
    bartv Member
    I doubt it - we require the 3mm minimum wall thickness everywhere..

    Bart
     
  3. tunabreath
    tunabreath Member
    Has the exclusion procedure for stainless steel parts recently been made more strict? The part shown above was printed once successfully (received by me) as it is shown in that picture (no reinforcement to the thin section) under a previous revision/file:
    http://imgur.com/jwzrZ

    Another part was printed twice (one under the current revision to a customer, once to me under a previous revision), but is now considered unprintable:
    http://imgur.com/3Mseo
    http://imgur.com/q7fvUuk
    (the red highlighted ribs have to be removed before use)
    http://imgur.com/hlAoj2S

    How far reaching are the advanced design rules for the stainless material? (what kind of maximum unsupported distance vs thickness, ribs/support options, etc.)
    Is a 3mm flat unsupported section preferable to a 2mm thick ribbed/cross structure?
    If I have to increase the total thickness on all of these parts, it's going to increase the cost quite a but, but also really increase the amount of material that has to be removed before installation.

    I'm not sure what the best way to proceed is.
     
    Last edited: Feb 9, 2013
  4. AmLachDesigns
    AmLachDesigns Well-Known Member
    But then again --> 61705

    If you search through the steel models, I am not sure that they all adhere to this 'rule'.
     
    Last edited: Feb 10, 2013
  5. bartv
    bartv Member
    @tunabreath: I don't think we've become more strict. Sometimes we find that we need several tries to sucessfully print a model though, and we may decide that it is becoming too expensive to produce (as in: we're actually losing money on the production).

    @tunabreath, @AmLachDesigns: Yes, it's true, I was a little too quick with the '3mm' remark. Successfully esigning for steel is a little more complicated than that - for example you may be able to print thinner structures provided that your structure is sufficiently self-supporting. Please have a look at the steel guidelines here:

    https://www.shapeways.com/materials/steel-design-guidelines

    Unfortunately not all these rules are easy to quantify and we rely on operators with a lot of experience in this material to make a judgement call on printability..

    Bart
     
  6. AmLachDesigns
    AmLachDesigns Well-Known Member
    I find this quite confusing: I cannot imagine moving any structure made of wet sand without it breaking. How is the print moved? Is it on some kind of transport plate or must the technician pick it up directly somehow?

    I am interested in making something that would be essentially a flat plate (approx. 180mm x 100mm), pierced in places and with raised detail in other places. The whole thing would be near and in some places below 3mm thick. Is this feasible or totally impossible?

    Thanks
     
  7. stonysmith
    stonysmith Well-Known Member Moderator
  8. AmLachDesigns
    AmLachDesigns Well-Known Member
    Thanks for that, I think I get the picture now.

    I will have to re-think this particular idea, clearly.