Design nylon parts that can be cleaned, assembled and used: wall thickness, powder escape, moving clearances, snap fits and the finish to specify.
A laser supplies local energy to selected polymer powder while the surrounding bed carries the geometry. The same thermal history that removes attached supports also makes cooling, refresh ratio and powder removal part of the process definition.
Prepare
Parts are oriented and packed in three dimensions. The system brings the powder bed close to its processing temperature.
Fuse
A laser traces the selected region of a thin powder layer, joining particles where the model is solid.
Repeat
The platform indexes and a fresh powder layer is spread. Unfused powder surrounds the parts instead of attached support structures.
Recover
The build cools before parts are excavated. Used powder is sieved and blended under the material/system workflow, then parts are cleaned.
This is the polymer SLS sequence described by Formlabs. Laser strategy, atmosphere, refresh ratio and cooling schedule are system/material-specific and can change properties, colour and dimensional behaviour.
SLS can suit ducts, clips and housings with geometry that is difficult to machine. Choose the exact powder and finishing route before freezing the design.
Shape
Loose powder supports the build without attached supports. Undercuts and nested features still need cleaning access; thermal distortion and orientation remain relevant.
Fit
Allow for dimensional variation, surface texture and the path used to remove powder. A visible CAD gap is not proof that the joint will move.
Load
Compare orientation-specific data for the named powder. Tensile strength alone does not predict a clip’s impact resistance or cycle life.
Batch
Parts can share a three-dimensional build. Savings depend on geometry, packing, cooling and finishing, rather than a universal break-even quantity.
A minimum feature proves that material can form. A working wall also has to resist handling, cleaning and the load in your assembly.
A short feature and a tall free-standing wall can need different design allowances. Check height, span and access for cleaning.
Ribs, a return edge and shorter unsupported spans can improve stiffness. Leave room to remove powder or supports.
Schematic illustrations; not to scale. Confirm the design for the chosen material, process and final use.
| Feature | Starting point | What to check |
|---|---|---|
| Walls | 0.8 mm starting pointStratasys Direct SLS wall study | The study found 0.6 mm possible but less stable. Increase thickness or redesign for long spans and loading; this is not a structural rating. |
| Pins | 0.8 mm exampleFormlabs Fuse 1, Nylon 12 | Short printable pins can still break during depowdering. Length and root geometry matter. |
| Through holes | 1.0 mm exampleFormlabs Fuse 1, Nylon 12 | Depth and cleaning access matter. Use a machined bore where concentricity or a fitted pin matters. |
| Separate mating parts | 0.2 / 0.4 mm gap examplesFuse 1 interface below / above 20 mm² | Clearance recommendations are not dimensional tolerances or interference-fit specifications. |
| Printed-in-place joints | 0.3 / 0.6 mm gap examplesFuse 1 interface below / above 20 mm² | Powder must be removable throughout the joint. Test the real interface before a batch. |
| Text and logos | Bold features; approve a sample | Face orientation, blasting and later smoothing change legibility. |
These examples apply to the cited process. A different powder, reinforcement, machine or geometry may require larger features; confirm the drawing requirements with the quote.
“Nylon SLS” covers products with different ductility, stiffness, atmosphere needs and printer compatibility. The powder-handling route belongs with the mechanical datasheet.
| Material family | Product examples | Selection direction | Performance evidence to compare |
|---|---|---|---|
| PA12 | Formlabs Nylon 12 EOS PA 2200 | General housings, brackets, ducts and repeatable functional prototypes. | Compare printer, atmosphere, refresh ratio, orientation, conditioning and surface state; a PA12 family name does not normalize the data. |
| PA11 | Formlabs Nylon 11 EOS PA 1101 | Ductile clips, impact-led geometry and flexible thin sections. | Use elongation and impact data from the named process, then test bend radius, conditioning and cycle life on the real mechanism. |
| Glass- or carbon-filled PA | Formlabs Nylon 12 GF Formlabs Nylon 11 CF | Stiff fixtures, stable housings and temperature-led tooling candidates. | Compare modulus with elongation and impact. Filler type, loading and orientation change behaviour; “filled nylon” is not one material. |
| TPU | Formlabs TPU 90A EOS TPU 1301 | Flexible ducts, padding, grips and lattice candidates. | Name hardness, section, compression set and tear requirements; apparent softness depends strongly on geometry. |
These manufacturer products are examples, not a FabDigit availability statement. Confirm printer compatibility, powder condition, finish and required material traceability with the order.
Use the live library to connect polymer grades with manufacturer powders and original sources. Powder, printer, refresh workflow and current order availability are confirmed with the quote.
5 material grades 32 manufacturer products
Explore the indexed grade and product pages here. A quote confirms the material, machine, finish and sourcing available for a specific order.
More SLS material products
A hinge, a snap and a press fit impose different loads. One clearance or tensile-strength value cannot describe all three.
| Mechanism | Design decision | Validate on the part |
|---|---|---|
| Cantilever snap | Lengthen the arm; radius the root | Specify insertion force, retention force and cycles. Thickness, undercut and deflection work together; no universal geometry guarantees thousands of cycles. |
| Living hinge | Compare PA11 and PA12 grades | Ductility does not establish a lifetime multiplier. Test bend radius, orientation, conditioning and fatigue. |
| Repeated screw assembly | Consider an insert or captured nut | Use the hardware supplier’s hole and boss specification; test pull-out and tightening torque. |
| Tapped or forming-screw hole | Choose the actual thread system | Tap drills and forming-screw pilots differ. Do not size every hole as one fraction of screw diameter. |
| Bearing or locating pin | Define the finished fit and datum | Request reaming or machining where needed, with fixturing that does not distort the part. |
| Constant preload | Account for creep and moisture | Check retention after the intended temperature, humidity and time under load. |
Powder removal is part of the geometry. Hollowing is useful only when the shell still works and the cavity can be cleaned.
Hollow geometry does not guarantee a hollow delivered part. Unfused powder, liquid resin or support can remain inside.
Provide accessible openings and a path through the cavity. Opening size depends on process, material, channel length and cleaning method.
Schematic illustrations; not to scale. Confirm the design for the chosen material, process and final use.
Wall distribution, cooling, orientation and moisture affect size. Identify critical features instead of applying one tolerance to every surface.
Required
Excavation removes the powder cake; blasting clears adhering powder and evens the grain. Both operations can stress fine pins and flexures.
Confirm: blast media/pressure, protected details, channel cleanliness and whether loose powder is allowed internally.
Colour
Dye penetrates a near-surface region rather than turning the full wall into one colour. Powder, pretreatment and colour all affect the result.
Confirm: named material, approved colour/texture sample, scratch exposure and final dimensions after the dye cycle.
Surface
Vapour or chemical smoothing modifies the polymer surface and may improve cleanability or appearance. It also softens edges and text.
Confirm: material compatibility, internal access, edge retention, fit, sealing and any regulated cleaning requirement.
Interface
Reaming or machining can create a functional seat; coatings add build. The part needs a datum and enough local stock or wall thickness.
Confirm: workholding, machining allowance, coating thickness, masking and inspection in the final conditioned state.
| Requirement | Useful specification | Why it matters |
|---|---|---|
| Dimensions | Datums, critical bores and allowed variation | Layer height is not accuracy. Do not add a blanket shrink allowance to CAD without agreement. |
| Flatness | Free-state or installed inspection condition | A shell can move when released from a fixture; ribs do not guarantee a flat part. |
| Dye | Substrate, colour and surface sample | Dye penetrates near the surface. Deep scratches or machining may reveal the base colour. |
| Vapor smoothing | Final fits, legible text and any leakage test | The surface is modified; do not infer watertightness from appearance. |
| Strength | Named powder and test conditions | Printed orientation and moisture conditioning affect the properties relevant to the load. |
DyeMansion reports about 0.2 mm dye penetration for EOS PA 2200 on its DM60 process; this is not a universal depth for every nylon or dye route.
SLS normally needs no attached supports because powder surrounds the part. Orientation still affects dimensions, texture and properties, and internal features must allow powder removal.
There is no universal SLS minimum. Stratasys Direct recommends 0.8 mm as a starting point in its wall study; the exact powder, machine, orientation, span and load determine the final design.
Yes, suitable nylon grades can serve these mechanisms. Validate flexure geometry, load, orientation and conditioning. A more ductile PA11 grade does not establish a fixed cycle life or a tenfold advantage over PA12.
Dye penetrates a surface region rather than the entire thick cross-section. The depth depends on the powder and finishing process; a cut or deep scratch can expose the base colour.
Compare specific materials, geometry, quantity, finished appearance and inspection requirements. Both can make functional nylon parts; neither has universally better accuracy, strength or cost.
Identify critical dimensions, functional limits and the measurement condition. Confirm achievable limits for that geometry and finish on the quote; use drilling or reaming for fits the printed surface cannot meet.
Send your model with quantity, critical dimensions and the intended use. The quote confirms material, finishing and inspection requirements for your part.
