Manufacturing Standards

Orders with Xometry will meet the minimum workmanship standards outlined below (as applicable to the process). We adhere to manufacturing standards ISO 2768 (medium/fine) for metal parts, 2768 (medium) for plastic parts, ISO and ANSI/ASME for threads. If your project requires a level of workmanship that goes beyond the standards listed below, please clearly list the requirements in your engineering drawings, purchase orders, or specifications.

Mill Steps, Tooling, and Chatter

• Surfaces without finish = as milled, can show tool marks but surfaces will be free of defects, including burrs, chatter, tool gauges, and will meet surface roughness specifications.
• Indicated critical surfaces will be free of mill steps and marks across the entire surface.
• Milled surfaces will meet surface roughness specifications.

Chips, Burrs, and Sharp Edges

• All exposed edges will be free of burrs, sharp edges, and metal slivers.**
• **Sheet cut parts are not fully deburred unless specified through a selected finish.

Foreign Object Debris (FOD)

• Surfaces will be free of cutting fluid, metal chips, foreign objects, and other debris.

Threads & Tapped holes

• Threads will be fully formed and cut to specified size and class indicated in provided drawings.
• Threads will be free of defects, notable damage, and contamination. Their shape will comply with the manufacturing standards (diameters, lengths, pitch, thread shape, chamfers)

Countersinks

• Countersinks shall be round and made to print specifications and allow the proper designed fit with the mating screw.
• Countersinks will be free of burrs, chatter, or other tooling defects.

Finished Surfaces Cosmetics

• Paint coverage on surfaces will be uniform, including adjacent materials of assemblies.
• Finished surfaces will be free of defects, including chips, scrapes, or other damage.

Plated Surfaces

• Plated surfaces will be uniform, including adjacent surfaces of assemblies.
• Plated surfaces will be free of machining marks, scratches, pits, protrusions, or visible bare metal.
• Some minor defects may be permissible in certain situations if they do not compromise the protective finish.

Painted Surfaces

• Painted surfaces shall be consistent and continuous in the finish.
• Painted surfaces shall be free of visible machining marks, scratches, abrasions, dust particles, fisheyes, orange peel, or bare metal.
• Painted surfaces should be reviewed against this standard at a distance of 50 cm at 1X magnification.

Mating and Flexible Features

• Xometry is not responsible for the fit of mating parts.
• Xometry is not responsible for the function of snap tabs, clips, or living hinges.

Model, Drawing, and Quote Discrepancies

Xometry is a model-based company, but there are times when a drawing may supersede what is derived from the CAD model. We put together a matrix to help you understand which file and which information we use as the source of truth to manufacture your parts. Unless you specify a requirement in the notes field of the Xometry Instant Quoting Engine®, all requirements will be derived from either the drawing, the CAD File or the quote itself.

A drawing is required for supporting information that a model cannot capture. Examples of this are GD&T callouts, tap sizes, inserts, surface roughness requirements better 125Ra µ, and both general (tolerance block) and specific tolerances.

Customer Order via the Instant Quoting Engine

Xometry’s Instant Quoting Engine is the leading information provider when the customer orders via our online Platform. Several options can be selected (see table aside).

Please note that while the matrix aside generally describes what document we will follow to manufacture your parts, your order may be placed on hold so our engineers can contact you to work out any discrepancies that may affect the cost, lead time, or manufacturability. To prevent such delays, the best practice is to carefully review your quote, ensure it matches your drawing requirements, and ensure you have uploaded the correct documents. In instances where a discrepancy is intentional, please make note of this in the part notes section while building your quote. Our engineers will update the instructions for our manufacturers once all discrepancies are cleared up.

A drawing is required for supporting information that a model cannot capture. Examples of this are GD&T callouts, tap sizes, inserts, surface roughness requirements better 3,2 Ra µ, and both general (tolerance block) and specific tolerances.

CNC Machining and Turning Standards

• For features of size (length, width, height, diameter) and location (position, concentricity, symmetry) ISO 2768 is standard unless otherwise specified.
• As machined surface finish is 3.2 μm Ra or better. Machine tool marks may leave a swirl-like pattern.
  Sharp edges will be broken and deburred by default. Critical edges that must be left sharp should be noted and specified on a drawing.
• Clear or transparent plastics will be matte or have translucent swirl marks on any machined face. Bead blasting will leave a frosted finish on clear plastics.
• General tolerances for orientation and form features are outlined below unless we have agreed to other tolerances in your Quote. These features include parallelism, perpendicularity, cylindricity, flatness, circularity, and straightness.

General Tolerances for Linear and Angular Dimensions

Form tolerances apply to metal machined components. Plastic and composite materials are typically double the tolerance amount.

Sheet Cutting Standards

• Thickness tolerances are independent of cutting tolerances, as they rely on the raw stock material’s tolerance range.
• Edge-to-edge tolerances is ±0.1 mm nominal on the top face of the plate/sheet.
• Thicker materials may have a tolerance deviation on the bottom face due to tapers inherent in laser cutting, waterjet cutting, or plasma cutting.
• Xometry cannot guarantee flatness callouts for sheet cut materials.
• Holes of 2 mm or smaller in diameter may be slightly larger than standard tolerances and not perfectly round due to material pierce happening near the hole’s profile.
• A small bump of material or a different edge condition may be present at the lead-in and lead-out in a cutting profile.
• Tabs may be present on parts under 5 cm to hold the workpiece during manufacturing using waterjet or fibre laser machines.
• Pre-finished or textured sheets, such as brushed or polished stock may have only one side with the cosmetic finish.
• Protective film may be shipped on cut products to prevent damage of cosmetic finishes.
• The edge condition of sheet cut materials will have vertical striations versus smooth edges.
• Large burrs and tabs will be removed, but parts are not manually fully deburred before shipment unless explicitly requested or an advanced finish, such as chem films or coatings, is requested.
• Some cut materials may show a small halo discolouration from backsplash or overspray near the cut edges.

Sheet Forming Standards

• Forming and bending: ±0.5 mm
• Bend to hole or feature: ±0.3 mm
• Linear dimensions excluding locations to bends: ±0.3 mm
• Angularity: ±2 degrees
• Surface roughness (blank material): Ra 3.2 μm max
• Surface roughness (timesave): Ra 3.2 μm max
• Based on technology sharp edges will be broken but not fully manually deburred. Critical edges that must be left sharp should be noted and specified on a print.
• Specific sheet metal designs require custom tooling and will be flagged for a manual quote: hems, curled flanges and rolled sheets, stamped parts, and welded assemblies. If your part includes these features, please allow our manual quote team to review and provide you with an accurate cost and lead time.

Sheet Metal Tolerances Continued

Flat Parts

Sheet metal parts that utilise stock material gauge thicknesses and require no bending or milled features. All flat sheet metal parts can meet a ±0.3 mm tolerance.

Simple Bend / One Surface

When designing parts with some type of bend with a standard bend radius, sheet metal tolerances are required to open. For simple bent parts, Xometry can offer a ±0.3 mm tolerance for dimensions across a single bend. The bend radius itself is constrained to a ±1.0°.

Multiple Surface Bends

For dimensions measured over multiple bends, Xometry can offer a ±0.5 mm.

Sheet Metal Tolerances Reference Table

SLS 3D Printing

• ±0.3% for parts bigger than 100 mm (±0.3 mm below 100 mm)
• Parts with thicker geometries, flat or broad parts (>18 cm), and parts with uneven wall thicknesses will be prone to significant deviations or warp due to variable thermal shrinkage and stress.
• Modelled threads or precision features may have limited functionality as printed. Tapping or the addition of threaded inserts is recommended for the best function. The material thickness should be at least 2 mm to ensure successful thread cutting or threaded insert implementation.
• Guaranteed tolerances may be possible with a manual quote review, and must be approved on a case-by-case basis.
• General tolerances apply before secondary finishing or post-processing unless otherwise specified.
• Standard-size holes will be drilled out if accessible, holes smaller than 1 mm, irregular, or deep holes may shrink or sinter shut.

HP MJF 3D Printing

• ±0.3% for parts bigger than 100 mm (±0.2 mm below 100 mm)
• Parts with thicker geometries, flat or broad parts (>18 cm), and parts with uneven wall thicknesses will be prone to significant deviations or warp due to variable thermal shrinkage and stress.
• Modelled threads or precision features may have limited functionality as printed. Tapping or the addition of threaded inserts is recommended for best function.
• Natural grey colour may be inconsistent depending on feature size and build orientation. Dyed black is recommended for production parts.
• Guaranteed tolerances may be possible with a manual quote review, and must be approved on a case-by-case basis.
• General tolerances apply before secondary finishing or post-processing unless otherwise specified.
• Holes smaller than 0.5 mm, irregular, or deep holes may shrink or sinter shut.

SLA 3D Printing

• Guaranteed tolerances may be possible with a manual quote review, and must be approved on a case-by-case basis.
• Modelled threads or precision features may have limited functionality as printed. Tapping or the addition of threaded inserts is recommended for best function.
• Tolerances for Standard and High-Resolution options are described in the table below
• General tolerances apply before secondary finishing or post-processing unless otherwise specified.
• Residue of supports and marks of supports after removal shall be present.

DMLS 3D Printing

• ±0.2% (±0.1 – 0.2 mm)
• However, Xometry does not guarantee tolerances on the first order of a new design. Tolerance expectations can vary across different materials (e.g. stainless steel versus aluminium).
• Internal stresses during build, support strategy, 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.
• Modelled threads or precision features may have limited functionality as printed. Tapping or the addition of threaded inserts is recommended for best function.
• Expected surface roughness is 150-400 µin RA, depending on build orientation and material used for the build.
• General tolerances apply before secondary finishing or post-processing unless otherwise specified.

FDM 3D Printing

• ±0.5% for parts bigger than 100 mm (±0.5 mm below 100 mm) for both standard and industrial resolutions
• Guaranteed tolerances may be possible with a manual quote review, and must be approved on a case-by-case basis.
• Xometry chooses optimal build orientation taking into consideration overall surface quality and minimum build time unless otherwise specified.
• Minimum resolvable feature size, including positive text features, is at least 0.9 mm (1.1 mm or greater is safest).
• Modelled threads or precision features may have limited functionality as printed. Tapping or the addition of threaded inserts is recommended for best function.
• Holes smaller than 2 mm, horizontal holes and protrusions will build slightly oblong due to stair stepping from layers.
• General tolerances apply before secondary finishing or post-processing unless otherwise specified.

Polyjet 3D Printing

• ±0.1 mm for the first 25 mm is typical, plus ±0.05 mm for every 25 mm thereafter.
• Minimum feature size of 1.2 mm can be built with consistency.
• Rubber-like materials represent an approximation of shore A values and may vary between geometries.
• General tolerances apply before secondary finishing or post-processing unless otherwise specified.

Carbon DLS™ 3D Printing

• ±0.1% (±0.1 mm)
• However, Xometry does not guarantee tolerances on the first order of a new design. Tolerance expectations can vary across materials (e.g., elastomeric versus rigid).
• Stresses during build, support strategy, and other geometry considerations may cause deviation in tolerances and flatness.
• Parts with thicker geometries, flat or broad parts, and parts with uneven wall thicknesses may be prone to significant deviations or warp.
• Modelled threads or precision features may have limited functionality as printed. Tapping or the addition of threaded inserts is recommended for best function.
• Improved tolerances may be possible with a manual quote review, after successful completion of a prototype build, and must be approved on a case-by-case basis.
• General tolerances apply before secondary finishing or post-processing unless otherwise specified.
• Areas with support structure may show raised bumps where the structure was removed. In certain materials, like EPX and SIL, supported areas may be more visible because post-processing options are limited.

Plastic Injection Moulding & Compression Moulding

The injection moulding and compression moulding tolerances are based on the DIN 16742-2013 standard.

• Typical mould machined tolerances are ±0.127 mm.
• Tighter tolerances can be requested and may increase the cost of tooling. Additionally, many tight tolerances require the mould to be manufactured, sampled, and groomed.
• Part-to-part repeatability is typically under ±0.1 mm.
• Lead time stated is for the first T sampling shipment. The remaining production time is confirmed after T sampling approval.
• Typical first article shipments are 5 pieces but may vary based on size, origin, and material.
• Xometry cannot guarantee a perfect colour match per Pantone / RAL or any other colour system. If an exact colour match is required, a customer must provide a Colour sample to Xometry by sending a flat piece of the targeted colour on the Quotation stage.
• All quotes are based upon the assumption that designs have an adequate draft, radii, and coring for manufacturability.

• Cores, side actions, and tooling strategy are determined by Xometry unless explicitly discussed.
• Gating, ejection, knit lines and parting lines are at the discretion of Xometry unless explicitly discussed.

Die Casting

• The die casting tolerances are based on the ISO-8062-3-2007 standard.
• Typical mould machined tolerances are ±0.0254 mm when machining the mould.
• Tighter as-moulded tolerances can be requested and may increase the cost of tooling. Additionally, many tight tolerances require the mould to be manufactured, sampled, and groomed.
• Critical toleranced features and surface finishes may require post-machining and should be noted in the quote prior to order. Post-machined features will follow Xometry’s CNC manufacturing standards.
• Xometry will produce die cast components according to the net-shape (as-cast) model provided by the customer. These models must contain appropriate material for any additional post-processing efforts, such as post-machining. It is recommended to provide the as-cast 3D model as well as the final model with any accompanying technical drawings.
• Part-to-part repeatability is typically under ±0.1 mm.
• The standard finish for die-casting is as-cast and cannot guarantee a specific Ra value without additional processing.

• The lead time is for the first T sampling shipment. The remaining production time is confirmed after the first T sampling approval.
• Typical first article shipments are 5 pieces but may vary based on size, origin, and material.
• All quotes are based upon the assumption that designs have an adequate draft, radii, and coring for manufacturability.
• Cores, side actions, and tooling strategy are determined by Xometry unless explicitly discussed and presented via Design for Manufacturer (DFM) report
• Gating, ejection, knit lines, and parting lines are at the discretion of Xometry unless explicitly discussed.
• Parting line(s) on die cast parts will be visible as a thin ridge travelling across the part.
• Cast parts may have one or many gate vestiges, which are trimmed, sheared, or ground off.
• Ejector pin marks will be present on die cast parts, resembling round flats.

Vacuum Casting

• Tolerance of 0.3% from the part’s nominal size. Irregular or overly thick geometries may cause deviances or deflection due to shrinkage.
• Surface finish is externally 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.
• Xometry might offer VDI-like surfaces on your final product for texturing effect of your prototype.
• Sharp corners and text may appear slightly rounded.

Thermoforming

Thermoformed part tolerances are determined by the coefficient of thermal expansion of the resin, extrusion conditions, type and temperature of the mould, consistency of the forming process, the method of trimming, and quality of trimming fixtures.

• For moulded-in dimensions of parts from a machined aluminium mould, use ±0.38 mm for the first inch, adding ±0.03 mm for each subsequent 25 mm
• For moulded-in dimensions of parts from a cast aluminium mould, use ±0.70 mm for the first 400 mm, adding ±0.025 mm for each subsequent inch.
• Trimmed dimensions, regardless of the mould but using CNC trimming equipment should have a general tolerance of ±0.38 mm. For hole diameters use ±0.13 mm.