Manufacturing Standards

Xometry, Inc.

Last Updated: 11/28/16

Unless we have agreed to other tolerances in your Quote, we will work to achieve and hold the tolerances noted below, which will vary per the primary manufacturing method you select.  Xometry has developed a comprehensive set of Design Guides to assist you in optimizing your design for manufacturing method ultimately selected, please consult them for key tips and tricks.  In the event of a conflict between the Design Guides and this set of Xometry Manufacturing Standards, these will control.

CNC/Machining

  • +.005”/-.005” local tolerances across most geometries.  Will vary for large parts, specifically when holding flatness over large parts after heat treatment.
  • Finish requirements for “As Milled” finish will have a minimum 125 surface finish for CNC parts.
  • Tapped holes not explicitly called out as Features on the quoted CAD model may be machined to the diameters specified in that model.
  • No surface treatments (e.g. anodize, bead blast, iridite, powder coat, etc.) will be applied unless you have paid for them and we have specifically acknowledged them.

Metal Additive Manufacturing

Xometry currently offers Direct Metal Laser Sintering (DMLS) and Metal Binder Jetting (BJ3D) to 3D print metals using additive manufacturing techniques.

DMLS

  • +/- 0.001” – 0.006” is typical for positive features, and +/- 0.004” – 0.006” for negative features such as holes, but will vary between geometries and materials (e.g. stainless versus aluminum).
  • Stress, supports and other geometry considerations may cause deviation in tolerances and flatness.  Items and geometries which require strict flatness are not a good fit for this process.
  • Theoretical maximum build volume of 9” X 6” X 6”.

BJ3D

  • Items and geometries requiring adherence to any tolerances are not a good fit for this process.
  • Shrinkage usually ranges from 0.8% – 2% during cooling depending on part size and geometry.  This shrinkage is often unpredictable and non-uniform. Part shrinkage may cause deflection of flatness and surfaces.
  • Internal geometries, such as holes and slots, may shrink by 3 – 5%.
  • Minimum resolvable feature size is 0.40”.
  • Theoretical maximum build volume of 29” X 15” X 14.25”.

Non-Metal Additive Manufacturing

Xometry currently offers SLS (Selective Laser Sintering), FDM (Fused Deposition Modeling) and PJ3D (PolyJet 3D) across a range of machine and material combinations.

SLS

  • +/- 0.005″ or +/- 0.002″ per inch, whichever is greater. Build area up to 13 x 13 x 20″ (13″ max dimension preferred)
  • Parts with thicker geometries, large broad parts, and parts with uneven wall thicknesses may deviate due to thermal shrinkage and stress.
  • Theoretical maximum build volume of 13” x 13” x 20″ (13″ max dimension preferred).

FDM

  • +/- 0.004″ or +/- 0.002″ per inch, whichever is greater. Build area up to 24 x 36 x 36″
  • Minimum resolvable feature size, including positive text features, is at least 0.035” (0.045” or greater is safest).
  • Theoretical maximum build volume of 24” x 36” x 36.”

PJ3D

  • +/- 0.004″, or +/- 0.001″ per inch, whichever is greater. Build area up to 19 x 15 x 7″
  • Theoretical maximum build volume of 19” x 15” x 7.”
  • Minimum feature size of 0.050” can be built with consistency.

Sheet Metal

  • +/- 0.010” – 0.020” is typical and highly dependent on geometric features like bends and weldments.
  • Xometry recommends staying above 14 gauge for best performance and designing with common gauge thickness.

Urethane Casting

  • +/- 0.010” or +/- 0.003” per inch, whichever is larger, is typical. Irregular or overly-thick geometries may cause deviances or deflection due to shrinkage.
  • A shrinkage rate of +0.15% can be expected due to thermal expansion of the liquid, and the response of the flexible mold.
  • Surface finish is external smoothed to a satin or matte surface. Grow lines may be present on internal or difficult-to-access features. Polishing or custom finishes must be clearly defined and agreed upon at the point of order.
  • We can offer urethane casted parts as large as 30” long.