What to expect from your 3D print
Every printing process has a character of its own. Pick yours below to see how your part will look and feel, plus the design numbers to check before you upload a file.
What to expect from your FDM print
FDM builds your part by drawing it in melted plastic, one thin layer at a time. It's fast, strong and great value, and like every manufacturing process it has a character of its own. Five minutes here can save a reprint later.
How it will look & feel
Layer lines are normal
Parts are built in layers around 0.1 to 0.3 mm thick, so you'll see and feel fine ridges, most visibly on curved and gently sloped surfaces. This is the signature of the process, not a defect.
Every layer has a seam
Each layer starts and finishes somewhere, leaving a faint vertical line on the part. We position it as discreetly as we can.
Surfaces differ by orientation
The face against the build plate usually has a different finish and may be smooth, glossy or textured depending on the build surface. Top surfaces show a subtle fill pattern, and steep undersides are the roughest. We orient parts for the best overall finish.
Colour is approximate
Filament colours vary slightly between batches, and screen renders rarely match physical plastic. If colour is critical, ask us for a sample first.
Strength has a direction
Parts are strongest across the layers and weaker along the bonds between them (the Z axis). Tell us which way your part is loaded and we'll orient it to suit.
It's a functional finish
FDM is the workhorse process, perfect for prototypes, jigs and end-use parts. If you need a glass-smooth or highly detailed surface, our SLA service may suit better.
Quirks & limitations to be aware of
Support marks
Overhangs extending beyond approximately 45° from vertical may require support material while printing, depending on the material, geometry and print settings. Removing it leaves slightly rougher patches on those surfaces. We clean these up, but a trace can remain.
Warping on large flat parts
Plastic shrinks as it cools, so big thin flat parts can lift or curve slightly at the corners. Thin sheets wider than ~15 cm are most at risk. We can't guarantee these stay perfectly flat.
Fine strings & blobs
The nozzle can leave wispy strings between features or the odd tiny blob on a surface. We remove these in finishing; very occasionally a small trace survives.
Sag on bridges
Plastic printed across an unsupported gap can droop slightly on its underside. Short bridges are fine; long ones look better with a support or a small design tweak.
Design numbers that matter
Thinner walls can often print, but are at your own risk and aren't covered for reprints.
Overhangs beyond ~45° from vertical may need support and can show marks where it's removed.
Holes commonly print undersize. Increase the CAD diameter by this much as a starting point, or drill/ream critical holes after printing.
Leave this gap on each mating surface between parts that assemble together. Tighter fits may need fettling.
Minimum gap between surfaces that must move freely. Below this they can fuse.
Pins and posts below 2 mm diameter are fragile and can snap in printing or shipping.
Minimum stroke width for embossed or engraved text to resolve cleanly.
Typical tolerance: ±0.25% or ±0.25 mm, whichever is greater.
Before you upload
Export at real-world scale, in millimetres. The most common issue we see is files exported 10× too small. Double-check one known dimension before you upload.
Make it watertight. Your model should be a single closed shell: no gaps, no overlapping bodies, no zero-thickness surfaces. We check every file, but file quality remains your responsibility.
Don't over-resolve. Detail finer than the printer's resolution just makes files huge. A clean STL under ~50 MB is plenty.
Flag the important face. We choose the orientation for strength and finish. If a particular surface must look its best, add a note at checkout.
What to expect from your SLA print
SLA prints your part by curing liquid resin with light, one ultra-thin layer at a time. It gives the smoothest surfaces and finest detail of any of our processes, and like every process it has a character of its own. Five minutes here can save a reprint later.
How it will look & feel
Smooth as standard
Layers are just 0.025 to 0.1 mm thick, so surfaces come out smooth with layer lines that are hard to see or feel. This is the closest 3D printing gets to an injection-moulded finish.
Colour & translucency
Resins have their own colour range and it can vary slightly between batches. Clear resins are translucent rather than optically clear with our standard finish, and may show faint internal structure. Additional sanding, polishing and coating can improve transparency.
Keep it out of the sun
Resin keeps reacting to UV light. Parts left in direct sunlight will yellow slowly and can become more brittle over time. Paint or a UV-resistant coat protects outdoor parts.
Crisp, fine detail
Sharp edges, small features and engraved detail resolve beautifully. If your part is all about the detail, SLA is the right process for it.
Rigid, but less forgiving
Strength is even in all directions, but standard resins are stiffer and more brittle than printed nylon: they snap rather than bend. Tough and flexible resins are available if your part takes knocks.
It's the detail process
Ideal for visual prototypes, miniatures, patterns and precise small parts. For rugged end-use parts or large functional pieces, our SLS or FDM services may suit better.
Quirks & limitations to be aware of
Support nibs
SLA parts print on a lattice of supports. Where each support touches the part it leaves a tiny nib. We remove and sand these back, but faint marks can remain on down-facing surfaces.
Post-cure bowing
Parts shrink very slightly as they cure, and long thin flat sections can bow a little in the process. Adding ribs or thickness to flat spans keeps them true. We can't guarantee thin sheets stay perfectly flat.
Hollow parts need drain holes
Enclosed cavities trap liquid resin, which adds weight and can crack the part as it cures. We recommend at least two drain and vent holes, each at least 3.5 mm in diameter, to allow effective resin removal, or ask us to print it solid.
Cup shapes create suction
Bowl or cup shapes facing the build plate act like suction cups during printing, which can distort or tear the part. A small vent hole in the design solves it; we'll flag this if we spot it.
Design numbers that matter
Recommended minimum for handling and reliability. Thinner walls can print, but are at your own risk and aren't covered for reprints.
Holes smaller than this can seal over with resin during printing.
Every hollow volume needs at least two, so resin can drain and vent effectively.
Starting clearance between separate mating components. Tighter fits may need fettling.
Minimum gap for print-in-place or moving parts. Below this they can fuse; printing separately and assembling is better still.
Pins and posts below 1 mm diameter are fragile and can snap during cleaning or shipping.
Minimum stroke width for embossed or engraved text to resolve cleanly.
Typical commercial tolerance: ±0.2% or ±0.2 mm, whichever is greater. Not a guaranteed specification.
Before you upload
Export at real-world scale, in millimetres. The most common issue we see is files exported 10× too small. Double-check one known dimension before you upload.
Make it watertight. Your model should be a single closed shell: no gaps, no overlapping bodies, no zero-thickness surfaces. We check every file, but file quality remains your responsibility.
Hollow with intent. If you hollow a part to save cost, remember the drain holes. If you'd rather we handle it, send it solid and add a note at checkout.
Flag the important face. We orient parts so support nibs land on the least visible surfaces. If a particular face must be flawless, add a note at checkout.
What to expect from your SLS print
SLS builds your part by fusing nylon powder with a laser, with the surrounding powder acting as its support. That means tough parts, no support marks and real design freedom, and like every process it has a character of its own. Five minutes here can save a reprint later.
How it will look & feel
A matte, grainy finish
SLS parts have a smooth but slightly powdery, matte surface, a little like an extra-strong mint. There are no layer ridges to speak of, but it isn't glossy. Polishing gives a noticeably smoother feel.
No support structures
Parts are surrounded and supported by powder during printing, so separate support structures are not required and there are no support-removal marks. Overhangs, interlocking parts and many internal features can print without supports, provided enclosed areas and channels allow adequate access for powder removal.
White as standard, dyeable
The nylon is a natural white and can be dyed (black is the most popular). Dye penetrates only the outer fraction of a millimetre, so deep scratches can show white underneath.
Strong & slightly springy
Sintered nylon is tough with nearly equal strength in every direction. Thin sections flex before they break, which makes SLS ideal for clips, hinges and end-use parts.
A fine, slightly porous surface
SLS nylon has a matte, finely textured surface and may retain a light powder residue when fresh. It can absorb some moisture or liquids unless it is sealed or appropriately post-processed. Soap, water and a soft brush clean fresh parts right up.
The functional workhorse
Ideal for end-use parts, complex geometry and small production runs. If you need a glossy surface or ultra-fine detail, our SLA service may suit better.
Quirks & limitations to be aware of
Powder in holes & channels
We clean every part, but deep or narrow channels can hold stubborn semi-baked powder. A needle or drill bit clears it. For long internal channels, a mid-way escape hole in the design helps a lot.
Warping on large flat parts
Nylon shrinks as it cools, so big thin flat parts can pick up a slight curve. Thin sheets wider than ~15 cm are most at risk. Ribs or extra thickness help; we can't guarantee thin sheets stay perfectly flat.
Small side-facing holes may print slightly oval
Holes printed sideways are built from stacked layers, so small ones (particularly below ~5 mm) may come out slightly oval or undersize. Drill or ream precision holes to final size when your part arrives.
Very thick sections may need modifying
Large solid volumes can cool unevenly and are more susceptible to shrinkage or distortion, so we may recommend hollowing or redesigning very thick sections. Hollow cavities normally need suitable openings so unfused powder can be removed; we'll agree any changes with you first.
Design numbers that matter
Thinner walls may be possible depending on size, shape and surrounding geometry, but are printed at your own risk.
Smaller holes clog with powder that's tough to remove. A drill bit sorts them out.
Hollowed parts need at least two escape holes so unfused powder can get out.
Minimum clearance between mating surfaces. For critical fits, expect testing or post-machining.
Minimum gap between surfaces that must move freely. Below this they can fuse together.
Pins and posts below 2 mm diameter are fragile and can snap during cleaning or shipping.
Minimum depth and stroke width for embossed or engraved text to resolve cleanly.
Typical tolerance: ±0.3% or ±0.3 mm, whichever is greater. Results vary with size, geometry and orientation; agree critical tolerances before production.
Before you upload
Export at real-world scale, in millimetres. The most common issue we see is files exported 10× too small. Double-check one known dimension before you upload.
Make it watertight. Your model should be a single closed shell: no gaps, no overlapping bodies, no zero-thickness surfaces. We check every file, but file quality remains your responsibility.
Mind the bounding box. Pricing follows the space your part occupies, so orient your model flat to the axes rather than tilted in 3D space before exporting.
Space nested parts. If you nest parts to save cost, keep at least 1.5 mm between them in every direction. Closer than this and they can fuse or spoil each other's finish.
Not sure? Just ask.
If anything here raises a question about your design, get in touch before you order. We're always happy to look over a file and advise.