FAQ
Before you order,
settle these questions
Grouped into five areas: ordering, files and data, materials and compliance, process and accuracy, and lead time and logistics. If your question is not here, email us or submit an enquiry.
- 5 groupsQuestion groups
- 20 questionsFAQ
- 1 business dayResponse time
- NDACan be signed first
Ordering
How does a first project start?
Send part files (STEP / 3MF / STL), the application, quantity and accuracy requirements by email or through the enquiry form. We reply within one business day with material recommendations, finishing tier, unit price and lead time.
Can I sample before committing to a batch?
Yes. Validate assembly and fit with 1–10 sample parts, then scale on the same process to 10–500 units with no repeat tooling-type fees.
What does the quote include?
Material, printing, cleaning and post-cure, the agreed finishing tier, standard inspection and packing. Manual polishing, painting and 100% inspection are listed separately.
Is an NDA required?
Optional. For unreleased products we recommend signing an NDA before sending files; requirements sent by email are also treated as confidential.
Files and data
Which file formats do you need?
STEP or 3MF preferred (keeps solids and assembly data), then STL and OBJ. Include 2D drawings or notes for assembly relationships, tolerances or surface requirements.
What happens if a file has problems?
We run a printability check first, listing issues with wall thickness, non-manifold edges, minimum features and assembly clearance, with revision advice before printing.
Can I send only ear-impression scan data?
Yes. We rebuild the shell surface from point clouds or scan files; physical impressions can also be sent to us for scanning.
Do I need to prepare the model for printing?
No. Send complete solids — supports, thickening and process allowance are handled at the slicing stage.
Materials and compliance
Which materials can be used for ear-canal contact parts?
We recommend a medical-grade resin intended for biocompatible use, with the wear duration and contact area stated on the order. We supply batch and certification documents for the material.
Can I specify a particular brand of resin?
We can assess it. Provide the grade and technical data sheet, and we will confirm machine compatibility and post-processing parameters.
Can clear parts be genuinely transparent?
They can approach optical clarity, depending on structural complexity. Step sanding and polishing raise transparency noticeably; polishing is manual work and appears in the quote.
What if the finished parts need sterilisation?
State the sterilisation method first (e.g. ethylene oxide, irradiation). Resins tolerate sterilisation differently, so we recommend a grade accordingly and explain the risks.
Process and accuracy
What is the smallest printable feature?
XY projection pixels are 22 μm, with reliable detail around 0.15 mm; minimum through-hole 0.4 mm and minimum stable wall 0.6 mm. Below these values we validate with a small sample first.
How do I choose layer height? Is 25 μm always better?
25 μm gives finer layer lines and smoother curves but doubles the layer count. For most hearables parts 50 μm already balances detail against efficiency.
Will surfaces show layer lines? Can they be polished?
Photopolymer parts still show fine layer lines on curved surfaces. The standard route is sanding plus blasting for a uniform matte finish; clear parts can add polishing.
Can you guarantee ±0.03 mm?
±0.03 mm applies to features up to 30 mm and requires suitable orientation and finishing tier. Beyond that, or for special fit requirements, we assess separately and state the achievable range.
Lead time and logistics
How long do samples take? And batches?
Standard parts ship a first article in 24–48 hours depending on height and finishing; 10–500 unit batches typically take 3–7 business days.
Can orders be expedited?
Orders can be slotted in. State the latest acceptable arrival date and we will give a feasibility call rather than agreeing and slipping later.
How are parts shipped, and who pays freight?
SF Express or JD Logistics by default, with freight collected on delivery or included in the quote; batch orders can ship by freight. Details are stated on the quotation.
What if dimensions are wrong on arrival?
Share your measured data alongside the inspection record supplied with the parts. Where the deviation is ours we remake them free of charge; where it comes from the drawing or tolerance callouts we explain it and give revision advice.
Still have questions?
Send the question together with your part background and we will answer for your specific part rather than with generic copy.