Oops...Seems your browser is blocking cookies. Please adjust your settings to accept cookies.
... Empty cart
Added to your cart

{{vm.userCart.LastAddedItem.Name}} Qty: {{vm.userCart.LastAddedItem.Quantity}} Price: {{vm.userCart.LastAddedItem.Price}}

Total Items: Subtotal:

Proceed to checkout

General Guidelines

Wall Thickness

Rubber-like | Wall Thickness

In general, we recommend a wall thickness of at least 1 mm. Large parts may require larger wall thicknesses or added ribs or fillets for reinforcement. 

For the Extra Smooth finish, we recommend a minimum of 2 mm. Please check all details by clicking on guidelines for extra smooth models in the menu on the left.

Please note that the Rubber-like material has a hardness of Shore A 90, which means it is a hard material on the Shore A hardness scale. To get a flexible design, it is advised to keep the walls below 5 mm. In general thinner walls will be more flexible and thicker walls will result in less flexible and harder sections.


Hollowing & Holes

Rubber-like | Hollowing & Holes

We advise hollowing out a solid model as much as possible, and when the wall thickness exceeds 20 mm. We recommend a wall thickness of 1-2 mm and the inclusion of at least two holes with a minimum diameter of 10 mm for powder removal.

It is possible to create holes or perforations and ducts. The recommended minimum diameter size of these holes is 2 mm but some post-production will be needed to remove excess powder. Some residual powder may be stuck on the inside of complex ducts. It is advised to design a strip or chain through the duct to help in dislodging the powder once the part has been printed. In general, complex holes or ducts require larger diameters in order to achieve thorough removal of the unfused powder.

Lattice Structures

Lattice structures allow you to change shock absorption characteristics, on top you can reduce weight and material. Keep in mind that you must maintain a minimum gap of 5 mm between the lattice beams so the unfused powder can be removed.

Interlocking Parts

Rubber-like | Interlocking Parts

It is possible to print interlocking parts and assemblies in a single build. Parts that are printed together should have a minimum clearance of 0.5 mm.

Embossed and Engraved Details

Rubber-like | Embossed and Engraved Details

For embossed or engraved textures, we advise a minimum thickness of 0.25 mm. For legible engraved or embossed text, we recommend letters with a minimum line thickness of 0.5 mm, a depth of 1 mm, and an overall height of at least 2.5 mm.

Guidelines for Grouped Models

It’s possible to have several individual shells within a single 3D file. If the shells are part of interlocking elements, such as chainmail, for example, consult the rules indicated in the “The Right Space Between Your (Moving) Parts” a paragraph earlier. If the shells in your design are not interlocking or intersecting, additional design rules and considerations can be found below.

O Part, Where Art Thou?

O Part, Where Art Thou?
If a single file contains several shells that are not connected or interlocking, this can cause considerable challenges for our production team. First, identification of all your parts or shells may be challenging. When producing your design, your parts are combined with parts from other orders in the 3D printer. Most printers have a fixed printing volume. To save time and costs, we fill up the machine with as many ordered parts as the build will allow. This virtual 3D layout is then used for printing. Once the printing process is finished, we end up with a block of powder with all the different parts inside. If you have uploaded multiple small, unconnected shells, you can see how it could be very difficult to go back and recognize all the different shells contained within the powder block. Therefore, to solve this issue, we only accept models that are connected. Due to the nature of the material, we do not accept parts that are enclosed in a container or box. Continue reading below for more details and some important consequences of these options.

Connecting Parts

Connecting Parts

One way of making sure all the shells in your design stay together and can be processed as one part is to connect the different shells with support beams. It is important that the parts are well connected and that the connection beams are strong enough. Use a minimum wall thickness of 3 mm as anything thinner will not be strong enough to support the different parts of your design.

The heavier/bulkier your individual parts are, the thicker the connecting beams should be. If the connections between the parts are too weak, there is a risk that your parts might get lost. You can prevent bulkier shells by hollowing them out. Just don’t forget to provide several large drainage holes so that the powder on the inside can be removed – otherwise, your part will not become lighter. The part’s wall should be less than 5 mm thick.

It’s also advisable to have 4 firm connections per shell. The larger the shells, the more difficult they are to connect properly. That’s why the sum of the dimensions of the imaginary box (X+Y+Z) around your design should be less than 350 mm.

Combining Parts on a Ring

Combining Parts on a Ring
If your parts have holes through them, another way to keep them connected is by combining them on a ring. Putting your parts on a key-chain style loop ensures that we can process your designs as one part. However, when grouping your parts with this method, we can no longer orient them individually or define the correct space between them. So to avoid any problems during the build, prepare your design with a minimum of 1 mm spacing between each part. The minimum thickness of the connecting loop should be 3 mm. Make sure to limit the number of parts on the loop as too many items or large and heavy parts will have a greater chance of causing the loop to break. Designs, where the chance of breakage is too high, will not be allowed.



Once printed, each model will need to be cleaned with a brush and sandblasted to remove the excess powder stuck to your model. This is the same for grouped models but in these cases, access to all of the parts is more difficult. Please be aware that some residual powder might be present when receiving your parts. To clean your parts further, the residual powder can be removed with a brush or compressed air.

Please be aware that grouped models are only offered in natural finish. Because of the limitations stated above for these types of files, a good result cannot be guaranteed. Other finishes can be achieved through various post-processing techniques but will require perfectly cleaned and fully accessible parts, which is not possible for grouped models enclosed in a container immediately upon printing.


The techniques for combining multiple parts into one file that are described above will not allow us to make accurate quality inspections, to provide optimal cleaning of each part by our production team nor to pack and protect each individual part in the best way for shipment. Grouped models are only offered in natural finish. Choosing these options implies that you accept these conditions and don’t mind getting your hands dirty to do some extra cleaning of your parts.

Guidelines for Extra Smooth Models

For this finish, your model is put into a chamber with a solvent that seals the surface by removing the porosity and change the grey color to black.

Pending post processing

Pending post processing

Due to nature of this post processing technique, your part will need to be suspended during this step. If your design has holes with a diameter above 1.5mm or hooks, we will use these for hanging. Large parts will require more suspension points than small parts due to their weight. If there are no holes or hooks foreseen, we will use metal wire or clamps to hang your part in the processing chamber.

Please be aware that these touch points will always leave a small marks on the model as these points will not be smoothed.

Wall thickness

Wall Thickness

The Extra Smooth finish is the result of an automated chemical smoothing process, which uses a solvent to seal the surface of the part by removing porosity. As the solvent reacts and is receptive to material, the best result can be achieved with bulky parts with homogenous wall thicknesses.

We recommend walls above 2 mm for the best result. Walls of 1 mm or below are less optimal as they will be smoothed less and have a higher chance of getting deformed during the process. Parts with a significant variation in wall thickness are likely to appear to be smoothed in an uneven way. So homogeneous wall thicknesses are recommended.

For the same reason, we strongly recommend filleting (rounding off) or chamfering perpendicular and sharp corners to ensure a homogeneous result. The larger the radius, the softer the transition will be as well as the outcome.

For surface details, we recommended embossing over engraving for the same reason.

Interlocking parts

Interlocking parts
As parts will be suspended in the processing chamber, chain mail or any other interlocking designs will stick together once the smoothing process is done. This is because during the process the different parts will be touching each other and will melt together because of the solvent. We therefore will not accept these types of geometries.

Variations & Accuracy

As the process is dependent on a lot of different aspects like orientation of the part, position in the smoothing chamber, other geometries in the chamber, etc some variations can be expected in smoothness especially for cavities, the inside of tubes and internal channels and as well as in color.

As the post processing technology is still in its trial phase, we cannot guarantee an accuracy similar to the natural finish which you would typically expect. The manufacturer of the smoothing process indicates a general accuracy level of ±0.4%. From our experience we see that the accuracy is highly geometry dependent and cannot assure the manufacturer's accuracy claim. For this reason, we do not ensure a perfect fit for matching or mating parts.

Design Specifications

Minimum Wall Thickness
1 to 2 mm (depending on finish)
Minimum Details
0.25 mm

±0.9%(XY) up to ±1.8% (Z) with lower limits on ±1 mm (XY) up to ±1.5mm (Z)

Maximum Size
  • 274 x 370 x 380 mm (Natural)
  • 150 x 150 x 150 mm (Black dye)
  • 256 x 340 x 360 mm (Extra Smooth)
0.5 mm
Enclosed Parts?
Interlocking Parts?