Fit tests before the tooling is ordered
A dimensional error in CAD costs nothing on screen. In an injection mould or 200 machined parts it gets expensive. A printed assembly sample shows you within days whether everything fits.
Samples in 2 to 4 working days
What a fit test shows
Questions only a physical part can answer.
Installation space
Does the part collide with cables, hoses or neighbouring parts?
Assembly sequence
Can the assembly be built in the planned order?
Tool access
Can the fitter reach every screw with a wrench or driver?
Clearance and interference
Do pins, bearings and lids seat the way they should?
Suitable materials
For pure geometry checks PETG or PLA is often enough. If clips or screws are tested too, we use PA12 or the later material.
- PETGTough everyday material with grade-dependent compliance options.
- PLAFast, affordable prototyping and visual parts.
- PA12Tough, low-friction nylon for functional mechanical parts.
- ASAThe outdoor specialist - ABS mechanics with true UV stability.
What we need for the fit test
- 01The assembly as STEP so we can see the mating parts.
- 02Which dimensions are critical and which only need to be roughly right.
- 03The later manufacturing process of each part.
- 04Whether you want variants with different clearances.
Why a cheap sample prevents expensive mistakes
Most assembly problems do not come from a single part but from the interface to other parts. A cable not modelled in CAD. A screw head that collides with the lid. A hole in the sheet metal part that is half a millimetre off.
A printed sample costs a fraction of a tooling change. That is why a fit test almost always pays off before injection moulding, casting or larger batches of machined parts are ordered.
Manufacturing data at a glance
- Location
- Schleswig, Germany
- Part size
- up to approx. 250 x 250 x 250 mm, larger parts split and joined
- Quantities
- 1 to several thousand, no minimum order quantity
- Tolerances
- approx. ±0.2 mm for PLA, PETG and carbon grades, ±0.3 mm for ABS, ASA and PC
- Layer height
- 0.10 to 0.30 mm
- Materials
- 20 engineering filaments from PLA to PA12-CF and PC FR
- File formats
- STEP, STL, 3MF, OBJ, IGES up to 200 MB
- Lead time
- 2 to 4 working days for samples, 4 to 15 working days for series
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Fit test FAQ
How accurate is a printed assembly sample?
Typically about ±0.2 mm for PLA and PETG. That is enough for most installation and collision checks. We discuss tight fits beforehand.
Can I test several clearance variants at once?
Yes. For example we print three holes with 0.1, 0.2 and 0.3 mm clearance side by side. You see directly which fit works.
Are samples larger than 250 mm possible?
Yes, we split the part and join it again. We place the split so it does not affect the test.
How do I get a price?
Upload your STEP or STL file in the instant quote. You see the price immediately, and we check the file for problems before production.
Which information is needed for Fit testing?
Send a STEP file where possible, together with quantity, operating temperature, load, environmental conditions and critical dimensions. This lets us define material, orientation, production strategy and inspection effort for the part.
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