Questions, answered properly.

Design around ±0.3 mm. That is the honest working figure, not a best case from a calibration cube. Holes come out slightly undersized because of how molten plastic behaves going round a corner, so a 5 mm hole often measures nearer 4.8 mm — add clearance, or drill it afterwards. If a dimension on your drawing has a tolerance tighter than that, printing is the wrong process and we will say so.

Usually, if it is designed for the process rather than adapted from a metal part. A printed part is strong across the layers and weaker along them, so which way up it prints matters far more than how much plastic is inside it. Past roughly 40% infill you are paying for material and time and getting almost no extra strength. See orientation and print strength.

PETG starts to soften somewhere around 80°C. In practice that means it is fine outdoors, in a garage, in a car interior through a UK summer, and around the cooler edges of an engine bay. It is not fine bolted to an exhaust, sitting in an oven, or going through a dishwasher on a hot cycle.

Up to 256 × 256 × 256 mm in one piece. Bigger than that gets split, and we will tell you where the split should go — a well-placed seam usually gives a stronger part than forcing a single piece into an awkward orientation. There is no lower limit beyond the £5 minimum part price.

STL is what the quote tool reads, binary or ASCII, and it is what every CAD package will export. STEP and 3MF are also fine — email those rather than using the tool. If all you have is a sketch or a photograph, that is a modelling job; see below. Full comparison: STL vs STEP vs 3MF.

Two options. Search Printables, Thingiverse or GrabCAD for your equipment make and model — a surprising number of replacement parts already exist and are free. Failing that, send us photographs with a ruler or caliper in shot and every measurement you can take, and we will quote to model it. Simple clips and brackets are quick; anything with curves, threads or a precise mating face is a real design job and priced as one.

Yes, every time. We slice it and look at what comes out. Holes in the mesh, walls too thin to survive, features that will need scaffolding through a visible face — all of it is easier to spot before the machine starts than after. If something looks wrong you get an email the same day, not a broken part a week later.

You do, entirely. We keep it only as long as the order needs, we do not reuse it, and we do not print it for anyone else. In return you are confirming you have the right to have it printed — we do not knowingly reproduce someone else's copyrighted or patented design.

For the vast majority of parts, yes. The tool reads your actual geometry and works from real material and machine costs, not a per-gram guess. Very thin walls or a shape needing a great deal of support can move the number, and in that case we contact you before anything is printed and you decide. What we never do is make the part and then present a bigger bill.

Because print time, not plastic, is most of the cost. A tall thin part with barely any material in it can occupy a machine for six hours; a squat solid one uses more filament and finishes in two. On top of the geometry there is a £5 minimum part price and a £5 handling fee per order, which covers the checking, the packing and the postage admin. That is why ordering four parts at once costs far less than four separate orders.

Card, through Square. The details go straight to Square and never reach our servers — we see that a payment succeeded and nothing else. For repeat trade work we can invoice instead; ask by email.

Yes. Fifty parts is routine. Repeat runs of something we have printed before are quicker and cheaper because the file is already set up and proven on the machine. If you expect to reorder, tell us at the start and we will keep the setup ready. See ordering multiple parts.

Standard (0.20 mm) unless you have a reason not to. Draft (0.30 mm) is cheaper and faster and perfectly strong — take it for anything hidden or purely functional. Fine (0.12 mm) is slower and dearer and only earns its keep on lettering, small detail, or a face somebody is going to look at closely. More: layer height and infill.

Black as standard, in the price. White for a small surcharge. Anything else, pick "Other" in the quote tool and tell us what you are after — we will confirm whether we can get it before you commit. We do not paint, sand or polish; parts go out as they came off the bed with the supports removed.

2–3 working days from payment for a normal order, including the post. Large batches take longer and we will give you a real date rather than a hopeful one. The machines run overnight, which is what makes that timescale honest rather than optimistic. Detail: how long printing takes.

• Free — collect from Mildenhall, Suffolk
• £3.95 — Royal Mail tracked, most UK addresses in 1–2 working days
• £7.00 — larger or heavier parcels

Every order gets a tracking page and an email at each stage, so you never have to ask where it is.

If the print failed — warped, split layers, a poor surface — we reprint it and you pay nothing more. Tell us within 14 days. If the model itself was wrong, we will show you what the slicer saw and quote for the fixed version. What we cannot refund is a part that is exactly what you specified but turns out not to fit, which is why a single test print before a batch is always worth the fiver.