Guides / Sourcing

How to Write an RFQ for a Machined Tungsten Part

Updated September 26, 2026 · Reviewed September 26, 2026

Tungsten parts get quoted slower and less accurately than steel or aluminum parts when the RFQ is missing information a shop needs to even start. Because tungsten grade, blank sourcing and process choice are so interconnected, gaps in the RFQ cost more time here than they would on a simpler material. This is a working checklist for what to include, plus the mistakes that most often send an RFQ back with questions instead of a quote.

Why tungsten RFQs need more detail than most

For a steel bracket, a shop can usually infer material grade, source the stock themselves and quote from the drawing alone. Tungsten does not work that way. The grade determines which process applies (standard CNC versus grinding and EDM), how the shop sources or presses the blank, and whether the part is even within the shop’s capability. A vague RFQ on tungsten does not just slow the quote down, it often gets no quote at all, because the shop cannot tell if the part is one they can run.

The checklist

1. Exact grade. State pure tungsten, heavy alloy with ASTM B777 class if known, W-Ni-Fe or W-Ni-Cu, or tungsten copper by ratio such as W70Cu30. If you only know the density you need, state that and let the shop or sourcing service recommend a grade.

2. A STEP file and a dimensioned PDF drawing. The STEP file lets a shop program the part without redrawing it. The PDF carries tolerances, surface finish callouts, thread specifications and any notes that a 3D model alone would not show clearly.

3. Tolerances on the features that matter. Tolerance only the dimensions that affect fit or function. On tungsten, every unnecessary tight tolerance adds more cost than the same tolerance would on steel, because inspection and scrap rates are higher.

4. Quantity and repeat volume. A one-off part is usually cut from bar or plate stock. A quantity in the dozens or more may justify a near-net sintered blank, which changes both the price and the lead time. Tell the shop your expected volume even if the first order is small.

5. Material source. State whether the shop should buy and certify the blank themselves or whether you are supplying certified material. Both are common; the RFQ just needs to say which.

6. Certs and tests required. Material certification, density testing or radiographic inspection all add cost and days to the schedule. List what your customer or application actually requires rather than defaulting to every test available.

7. Magnetic requirement, if any. If the part must be non-magnetic, for example near MRI equipment or sensors, say so explicitly and specify W-Ni-Cu. A shop defaults to whichever binder is standard for them, which is often W-Ni-Fe.

8. Region preference, if any. If you need the shop in a particular region for logistics or compliance reasons, state it. Otherwise leaving the region open widens the pool of shops that can quote.

Two RFQs for the same part, and why one gets quoted faster

Consider a shielding insert, roughly 40 mm across, that needs to be non-magnetic and dense.

A thin RFQ might read: “Need a tungsten shielding part, see attached sketch, qty 20, ASAP.” This tells a shop almost nothing it needs: not the grade, not a usable drawing, not whether magnetism matters, not a real deadline. Expect this to sit unanswered or come back with a list of questions before anyone quotes it.

A complete RFQ for the same part reads like the sample in the next section: exact grade and binder, a real drawing with tolerances, a quantity with repeat volume noted, and a stated magnetic requirement. The difference between the two is not effort, it is including the handful of facts a shop actually needs to say yes or no to the job.

What a complete RFQ looks like in practice

A well-specified tungsten RFQ reads something like this:

Material: Tungsten heavy alloy, ASTM B777 Class 3, W-Ni-Fe. Quantity: 25 pieces, expect repeat orders quarterly. Drawing attached (STEP + PDF), critical tolerance ±0.02 mm on the bore diameter, general tolerance ±0.1 mm elsewhere. Material certification required. Region: no preference.

That single paragraph gives a shop everything it needs to quote without a round of clarifying questions, which is usually where the delay happens on less complete requests.

Common mistakes that slow down a tungsten RFQ

• Saying “tungsten” without a grade. As covered above, this is the single biggest cause of delay, since grade decides the process and often the shop.
• Attaching a picture instead of a dimensioned drawing. A photo or a rough sketch cannot carry tolerances, and a shop cannot quote what it cannot measure.
• Leaving quantity as “TBD” with no range at all. Even a rough range, such as “probably 10 to 50,” lets a shop reason about blank strategy. A completely open quantity field usually gets a generic, conservative quote or no quote.
• Requesting every possible test “to be safe.” This inflates the quote for tests your project may not need. List only what your application actually requires.
• Not mentioning repeat business. A shop pricing a one-time order of 20 parts prices differently than one pricing 20 parts every quarter. If you expect to reorder, say so, since it can change both price and blank strategy.

What to write when you do not know the exact answer

Not every buyer has every field nailed down before the first RFQ goes out. The table below covers what to write instead of leaving a field blank.

If you do not know…	Write this instead of leaving it blank
The exact ASTM B777 class	The target density, or the application, so the shop or mill can recommend a class
The exact tolerance	Your best estimate, marked “to be confirmed,” rather than no tolerance at all
Final quantity	A realistic range, such as “10 to 50,” and whether repeat orders are likely
Whether you supply material	State that this is undecided and ask the shop to quote both ways
Required certifications	State what your customer or program generally requires, even if the exact document list is not final

A field marked “to be confirmed” with a reasonable estimate is far more useful to a shop than a blank field, since it lets them quote something close to the final part instead of guessing or declining to quote at all.

What happens after you send it

Once your RFQ is complete, it goes into a short anonymous preview that shops see before your contact details are released: part type, grade, size, quantity and tolerance, nothing that identifies you or your company. We match it with up to three shops that cut that grade and size, and they contact you directly, typically within 24 business hours. You never pay to send an RFQ or to receive quotes.

Once the RFQ is written, the guide to custom tungsten parts covers the quote, price terms, delivery and acceptance.

If you are still deciding on a grade before you finalize the drawing, what each tungsten grade allows covers the tradeoffs between pure tungsten, heavy alloy and carbide. If cost is the open question, see what drives the price of a machined tungsten part. When your drawing is ready, send your RFQ using the checklist above.

Frequently asked questions

Sources

• Wikipedia - Tungsten
• ASTM B777 - Standard Specification for Tungsten Base, High-Density Metal
• Wikipedia - Request for quotation

Keep reading

• MIL-T-21014 vs ASTM B777: How to Convert an Old Tungsten Heavy Alloy Callout
• How to Source Machined Tungsten Shielding and Counterweights