What We Check Before a Part Ships
What every part is checked for, what we deliberately do not do, and what ±0.5 mm means when a part has to fit something.
Every part is looked at by a person before it goes in a box — for the failures that actually happen on an FDM machine, and with the hardware fitted and the product assembled in the same pass. Here is exactly what gets checked, where you should test for yourself, and what our published tolerance means when a part has to fit something.
What gets checked on every part
- First layer and base: no lifting, no warped corner, nothing that has come off the plate.
- Surface: stringing, blobs, visible layer shifts, and under-extrusion that shows as gaps in the walls.
- Completeness: every feature present — no missing tab, hole, thread or lid.
- Colour: the right filament, and no mid-print colour change from a spool running out.
- Supports removed, with no stubs left where a hand or a surface will meet them.
- Hardware installed where the product calls for it: magnets, threaded inserts, screws.
A part that fails any of those goes back to print rather than into the box, at our cost, and the order carries on as Reprinting.
The standard
Would we be happy to receive this in a parcel we paid for? If not, it is printed again.
And thenA part that fails goes back to print, at our cost, and the order carries on as Reprinting.
Where the check stops
So you know what to test yourself before you list:
| Not done | What that means for you |
|---|---|
| Every part measured with calipers | Dimensional checks are done on parts that have to fit something, not on all of them. |
| Destructive or load testing | If a part carries weight or force, test a sample yourself before you list it. |
| Colour matched to a reference chip | Filament colour varies between batches. Order a sample if exact colour matters. |
| Surface finishing | We do not sand, paint, smooth or dye. Parts ship as printed, supports removed. |
| Food, skin or toy safety testing | We make no claim of any of these. Do not list a part as food-safe. |
- Every part measured with calipersWhat that means for youDimensional checks are done on parts that have to fit something, not on all of them.
- Destructive or load testingWhat that means for youIf a part carries weight or force, test a sample yourself before you list it.
- Colour matched to a reference chipWhat that means for youFilament colour varies between batches. Order a sample if exact colour matters.
- Surface finishingWhat that means for youWe do not sand, paint, smooth or dye. Parts ship as printed, supports removed.
- Food, skin or toy safety testingWhat that means for youWe make no claim of any of these. Do not list a part as food-safe.
The reliable way to a part you can trust every time is to design in the margin — fewer overhangs, thicker walls at stress points, clearance on anything that fits. The design check runs those rules on your numbers.
What the tolerance actually means
Parts are produced to ±0.5 mm or ±1%, whichever is greater. On a 40 mm feature that is ±0.5 mm; on a 200 mm one it is ±2 mm. FDM shrinks slightly as it cools, and that shrinkage scales with size, which is why the percentage matters on bigger parts.
The tolerance, applied
±0.5 mm or ±1%, whichever is greater
±0.50 mm
It will measure between 39.50 mm and 40.50 mm.
Band shown ten times larger than scale.
Design the hole at
6.2 mm
0.2 mm of clearance is the working rule for a slip fit. Within the tolerance that hole can measure 5.70 mm to 6.70 mm — so order one sample, try the real 6 mm part in it, and adjust before you list. A hole drawn at exactly 6 mm will not take it.
The tolerance is our published commitment on every part. Where one dimension is critical, say so when you order and we check that dimension. Choose assembly and we fit the magnets, inserts and screws ourselves, for $1 a part.
When something gets through
Checks catch most of it, not all of it. If a defect reaches your customer, open the order and choose Get help with this. That opens a support thread tied to that order, and the team works out whether a replacement or a refund is right. You refund your customer from your own store; we refund the make cost to your card if that is the outcome.
The mechanics of that, and who pays in each case, are in what happens when a print fails.
FAQ
Yes, every part gets a human look before packing: first layer and base, surface defects, completeness, colour, support removal and hardware. Parts that fail are reprinted at our cost. We do not measure every part with calipers, and we do not do destructive testing.
±0.5 mm or ±1%, whichever is greater. On a 40 mm feature that is half a millimetre; on a 200 mm part it is about two. Design clearance into anything that has to fit a bought component, and test a sample first.
Close, but filament colour varies between batches, and we do not colour-match against a reference. If exact colour continuity matters — a product sold as a set, for instance — order the whole set at once.
No. Parts ship as printed with supports removed. If your product needs a painted or smoothed finish, a service that offers post-processing is a better fit than us.
Open the order and choose "Get help with this". Our team decides between a replacement and a refund of the make cost. Your customer’s refund comes from your store, because that is where they paid.
Order one. Hold it.
A single sample costs one unit and it is the only way to know what your buyers will hold. Every part after it gets the same check.
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