Q&A

Here you will find answers to the questions we are asked most often about TDC’s services and technologies.

If your question is not covered here, or if you would like to discuss something more specific, please get in touch through our contact form.
We are also happy to set up an online meeting if you would prefer to discuss things directly.
A member of our team will get back to you promptly.

1. Machining & Technology

Q. What materials can you process?

We have machined over 230 different materials, including metals, ceramics, glass, and resins.
We can also take on new materials and specialized composites.

You can see examples of our work on the pages below.

Machining Examples: our work broken down by material
TDC’s Surface Roughness Achievements: surface roughness by material

Q. Is there a size limit?

[Minimum size]
We have produced micro-cubes measuring 0.05mm on each side.
You can find the details under [Examples of TDC’s lapping process] on our About Lapping and Polishing page.

[Maximum size]
We can handle up to 600 x 1,500mm for grinding, and up to approximately 1,000mm (1 meter) in diameter for mirror polishing.

Q. Is there a weight limit?

We can handle workpieces weighing up to 1.5 metric tons (1,500kg).
Our factory is equipped with an overhead crane rated at 1.5 metric tons, so we are set up to handle large workpieces.
If your parts are on the heavier side, letting us know in advance helps us prepare.

Q. Can you also make the surface rough?

Yes. We can produce anything from a high-gloss, ultra-precision mirror finish to a matte finish (a frosted-glass look), depending on the surface roughness you need.
In addition to polishing, we also offer cutting and grinding.

[Capabilities and typical accuracy]

• Types of finish: Polishing (from mirror finish to matte), cutting, grinding
• Accuracy: For an ultra-precision mirror finish (Ra1nm or below), we can hold in-plane variation to around ±10%. With rougher finishes such as matte, the in-plane variation will be larger than with a mirror finish.

The result also depends on the material and the size of the workpiece, so please start by telling us the specifications you have in mind.

Q. Do you also handle surface treatment such as plating and coating?

Yes. We can take on polishing and surface treatment together as a single order.
For the surface treatment itself, we work with partner companies we have known for many years, and TDC serves as your single point of contact, managing the entire process.

[Examples of combined processes]

• Polishing + plating or coating
• Precision finish polishing after plating or coating

Bringing several processes under a single point of contact keeps the ordering and coordination work on your side to a minimum, and lets us deliver a high-quality finished product as a one-stop service.

Please feel free to ask us about surface treatment along with your polishing requirements.

Q. How do you measure flatness?

At TDC we measure flatness using the following instruments, choosing between them according to the workpiece.

• Non-contact measurement (laser interferometer): Handles sizes up to 18 inches. Captures even very fine variations in form.
• Contact measurement (CMM): Suited to large workpieces and complex geometries.

For a full list of our measuring instruments and their specifications, please see our Measurement Equipment page.

Q. Can you measure film thickness?

Yes. As part of the film-thickness control involved in our polishing work, we perform the following measurements.

• Plating thickness on metal: Eddy current coating thickness gauge
• Optical crystals and similar materials: Optical Nano Gauge (Hamamatsu Photonics)

We use these for quality checks on the work we polish, and we are also happy to take on measurement-only requests.
Please get in touch if your work calls for tight film-thickness control.

2. Lead Time, Cost & Stock

Q. How long is the lead time?

It depends on the size, quantity, and the work involved, but we can adjust to fit your schedule.

If you supply the material and we handle the polishing, it is typically a few days to a week.
If we handle everything from sourcing the material to the finished part, it is usually two to three weeks.

If you are working to a tight deadline, let us know when you get in touch and we will do what we can to accommodate it.

Q. How much does it cost?

We calculate the price from the machining time required, taking into account the difficulty of the work, the material, the size, and the quantity.
Turnaround on quotes varies depending on what is involved, but we normally get back to you within a few days, so please feel free to reach out.

Q. Do you keep items in stock?

Our products are made to order, built to the specifications you give us.
If your timeline is tight, we will do what we can to adjust, so please talk to us about it.

Test pieces and shims are items we normally keep in stock, and they are available for same-day shipping.
If you would like to order from stock, please send us a message through our contact form.

You can read more about our ultra-precision shims on the page below.

Ultra-Precision Custom Shims

3. Support & Shipping

Q. Can I speak with an engineer?

At TDC our sales staff act as your customer support team, so questions about the technical side, lead times, and quality can all be handled through a single point of contact.

Our support staff have a technical background and handle inquiries in English, so you can discuss specifications with them much as you would with an engineer.
If you would rather speak with someone technical than with a salesperson, please do not hesitate to reach out.

Q. Which countries can you work with?

As a rule, we can work with customers in any country we are able to ship to.

To date, we have worked with customers in 18 countries around the world.

Online meetings are also an option if you would like to talk through your requirements.
Please feel free to reach out through our contact form.

Q. How are orders shipped?

We ship worldwide using international couriers such as FedEx, DHL, and UPS, selecting the carrier according to the size and nature of the shipment.
For large or heavy items, we arrange shipping on a case-by-case basis.

If you have a preferred carrier, we are happy to use it. Just let us know.

TDC Information