How to get a replacement part 3D printed from a broken original
The short answer
If the part is broken and the spare is gone, a 3D printed copy is often the fix. You need a 3D file of the part. Look for one online first. If no one has shared a model, measure the broken original and model it, or have someone model it for you. Then upload the file for an instant price. We print from files, so the broken part is your reference, not something we scan.
Step 1: check whether a file already exists
Many common replacement parts have already been modelled by someone else. Knobs, battery covers, clips, appliance feet, caravan latches and blind fittings turn up all the time.
- Search Printables, Thingiverse and MakerWorld with the brand, the model number and the part name.
- Read the comments. People often say whether it fitted or needed a tweak.
- Check the licence. Most free models are fine for a personal replacement part.
- Check whether the maker still sells the spare. Sometimes the genuine part is cheap and the better option.
If you find a file, download the STL or STEP and skip to step 4.
Step 2: measure the original
Good measurements are most of the work. A cheap set of digital calipers from a hardware store makes this far easier than a ruler.
- Measure the overall length, width and height.
- Measure every hole: its diameter and the distance between hole centres.
- Measure wall thickness and the size of any tabs, slots or clips.
- Measure what the part fits onto as well, such as the shaft a knob slides over or the panel a clip grips.
- Take photos from every side with a ruler in shot.
If the part is in pieces, tape or glue it back together before you measure. Guessing the missing bit is where most fit problems start.
Step 3: turn the measurements into a 3D model
Simple parts are very doable yourself. Free tools like Tinkercad handle boxes, cylinders and holes. FreeCAD and Onshape go further for parts with more detail. Export a STEP if your program can, because it keeps the exact geometry. An STL is fine too.
A few rules make a printed copy work:
- Keep walls at least 1.2 mm thick.
- Holes print slightly small. Make them a touch bigger, or tell us the size they need to be.
- Detail finer than about 0.5 mm won't print cleanly, so leave out tiny text and fine texture.
- Look at where the original broke. Add a little thickness or a rounded corner there so the copy doesn't break in the same spot.
If modelling isn't for you, ask a handy friend, a local makerspace or a freelance CAD designer. You can also describe the part in the notes when you request a quote. We don't offer a full design service, but if it is a simple measured part we may be able to help, and we will tell you either way.
Step 4: pick the right material
Think about why the original failed and where the new one will live.
- Snapped clip or bracket: PETG or PCTG. Both bend a little before they break.
- In the sun or a hot car: ASA. See why PLA warps in a hot car.
- Rubber foot, seal or grommet: TPU 95A.
- Indoors and mainly for looks: PLA.
Most original parts are injection moulded. A printed copy behaves a little differently because it is built in layers and is weakest between them. We orient every part for the best result, so you don't need to. The which material help page covers the common cases.
Step 5: get a price and order
Upload the file to the quote tool. Check the size shown under the file name against your measurements. If it looks 25 times too small, switch Model units to Inches. Pick a material and colour and the price updates as you go.
Use the notes for anything that has to fit, such as "the hole must slide over a 6 mm shaft". We check every file by hand before printing, and if something looks wrong, we email you first.
There is no minimum order. Each order has a $16.50 inc GST setup fee and each part is priced the same whatever the quantity, so it is often worth printing a spare at the same time. Standard orders are dispatched in 3 to 5 business days, express in 2, and we post anywhere in Australia. You can pay by card, or ask us to check the price first.
Is 3D printing the right fit for this part?
We don't print food contact or medical parts, and printed plastic is not a substitute for safety-critical parts. Very fine detail, parts under constant heavy load and parts that sit right next to engine heat may need a different process. If you are not sure, the help centre has more answers, or email us before you order.