Do Dimensions Change While Printing?

Discussion in 'Design and Modeling' started by PegasusDesigns, Oct 15, 2018.

  1. Hey everyone!

    I've always heard people talk about this, but I've never really thought it was possible. Many people have said that they've received 3D prints with certain dimensions changed like a model slightly longer than it should be and so on.

    I never really thought much of it until today when I received my order. I have a small 1:87 scale NG locomotive designed and I had it 3D printed. The kit is a multi-part kit and therefore the cab, chassis and bonnets/bodies are all different parts. They've been designed to slot together during assembly.

    Though this is my first time buying it, it's not the first time it is being 3D printed. I've had atleast 7-10 of these sold via my shop. None of my customers have had this issue, but mine turned up with the guides to slot the parts together being the same size as the actual part which is wrong. The guides are supposed to be smaller than the part. Basically the guides which can be considered as 1mm x 1mm raised detail have turned out to be 1mm x 2mm raised detail.

    Is there anything I can do about it? Unfortunately I cannot sand off the guide or the accompanying part as they both have very fine details that have printed quite well. Infact this 3D printed kit of mine is one of the best 3D prints I've ever received from Shapeways. It's just a pit that the dimensions of the guides have changed only on mine and it hasn't affected the 3D prints of my customers.

    I also received my kit with a few details missing. There was nothing in the zip-bag or the bubble wrap of the box as I checked very carefully.
     
  2. crashtestdummy
    crashtestdummy Well-Known Member
    Yes its possible an it happens with any manufacturing process. The amount of variation is called the tolerance in the manufacturing world. for example :
    Fine detail plastic
    ±0.1- 0.2 mm for every 100 mm

    So if your model is 100mm (or about 3.9 inches if you don't use the Communist measuring system) the part can be bigger or smaller then specified by .2mm or 99.8mm to 100.2 mm

    As for the missing parts contact customer service ASAP.
     
  3. Hello @crashtestdummy,

    Thanks for clarifying that. I've managed to work around the error by carefully sanding down half the required amount from each side. Now it is pretty much alright.

    I shall contact Shapeways' Customer Care as soon as I can.

    Regards