# Technical data sheets

Interpreting manufacturer properties and processing guidance through test conditions, variant scope and the distinction between typical values and specifications.

Reviewed: 2026-11-02

Tags: sourcing, documents, product-data

A technical data sheet (TDS) describes a supplier's product, selected properties and application or processing information. Its evidence can support material comparison and process understanding, but the title does not establish that every listed value is a contractual acceptance limit or that every delivered batch was tested for it. Product identity, variant, test conditions and the supplier's qualifiers determine the meaning of the numbers.

For example, 3M's **February 2016** DP420 family sheet labels its data representative or typical and unsuitable for specification purposes. [3M DP420 technical data, p. 1](https://multimedia.3m.com/mws/media/1235389O/dp420-technical-data-sheet.pdf?fn=DP420.pdf)

## Original example: mass and volume ratios

The cited DP420 family sheet gives **base:accelerator = 2:1 by volume** and **2:0.97 by weight**. These are distinct bases. [3M DP420 mix-ratio table](https://multimedia.3m.com/mws/media/1235389O/dp420-technical-data-sheet.pdf?fn=DP420.pdf)

For an original calculation using those stated inputs, a hypothetical **100 g total** mixed amount corresponds to base mass 100 × 2/2.97 = **67.34 g**, and accelerator mass 100 × 0.97/2.97 = **32.66 g**. Applying 2:1 by mass instead would give 66.67 g and 33.33 g. The latter is not the sheet's stated weight ratio, even though both mixtures total 100 g.

For a hypothetical **300 mL combined dispensed volume**, the 2:1 volume ratio corresponds to **200 mL base and 100 mL accelerator**. This arithmetic does not convert those volumes into the masses above without suitable density information, nor does it establish a suitable manual mixing method or batch size. It illustrates why a ratio detached from its basis can misrepresent the source.

A ratio tolerance would require separate evidence. The arithmetic cannot determine whether a deviation is acceptable, whether the material cured properly or whether an altered mixture meets the product's performance claims.

## Typical, nominal and specified properties

A typical value characterizes expected behavior under the stated conditions; it is not automatically a minimum or maximum. A nominal composition can describe a formulation target rather than an exact batch analysis. A specification limit is an acceptance boundary only within the document or agreement that establishes it.

Ranges also have different meanings. A viscosity range, operating recommendation, measurement interval and statistical spread are not interchangeable. A sheet may include several kinds of information in adjacent tables without making them equivalent. Its notes and headings are therefore part of the technical claim, not optional decoration.

As explanatory synthesis, a useful comparison has a common property definition and compatible measurement conditions. Two numbers with the same unit can still describe different tests. A larger value is not inherently better if it reflects a different substrate, temperature, strain rate, cure state or failure mode.

## Measurement method can change the number

Henkel's **LOCTITE 243 TDS, April 2025**, lists viscosity at 25 °C as **1300–3000 mPa·s** for a Brookfield RVT setup with spindle 3 at 20 rpm, and **350 mPa·s** for cone-and-plate measurement at **129 s⁻¹**. The product is described as thixotropic. These values are not a contradiction resolved by choosing the larger number: their measurement conditions differ. [Henkel LOCTITE 243, p. 1](https://datasheets.tdx.henkel.com/LOCTITE-243-en_GL.pdf)

The same sheet presents separate cure-speed relationships for substrate, bond gap and temperature. An isolated “cure time” would omit those dependencies. A property measured after a stated cure also cannot be assumed to apply immediately after application. [LOCTITE 243 curing-performance scope](https://datasheets.tdx.henkel.com/LOCTITE-243-en_GL.pdf)

Test-method identifiers provide context, but the specimen and preparation still matter. Adhesive lap shear, peel and bulk tensile testing impose different loading and geometry. A lap-shear result is not a general allowable stress for every bonded structure, even after converting its units.

## A named example of test-condition boundaries

Wall Colmonoy's Nicrobraz 30 sheet, printed **©2021**, identifies **BNi-5** filler and reports room-temperature testing on **304 stainless steel brazed at 1177 °C**. Its **2T lap joint with 0.05 mm gap** has reported failure shear stress **120.7 MPa**; the **butt joint with 0.05 mm gap** has reported failure tensile stress **352 MPa**. T denotes parent-metal thickness. [Nicrobraz 30 TDS, pp. 1 and 3](https://metals.wallcolmonoy.com/hubfs/Wall-Colmonoy_Nicrobraz-30-TDS_July2021.pdf?hsLang=en)

These are different joint tests, not competing measurements of one universal “braze strength.” The supplier itself notes dependence on base material, thermal profile and joint design and the possible need for specific joint testing. A general product sheet can explain behavior without establishing an application-specific design allowable. [Nicrobraz 30 joint-strength discussion](https://metals.wallcolmonoy.com/hubfs/Wall-Colmonoy_Nicrobraz-30-TDS_July2021.pdf?hsLang=en)

## Product families and document age

The cited DP420 sheet distinguishes Black, NS Black, Off-White and LH; some properties are expected to be similar rather than separately measured. That distinction limits variant-level comparisons. [3M DP420 family scope](https://multimedia.3m.com/mws/media/1235389O/dp420-technical-data-sheet.pdf?fn=DP420.pdf)

A printed revision date identifies the source version, not a manufacturing or expiration date. The 2016 DP420 sheet here is a historical illustration, not a current-edition claim for every SKU. A recent webpage crawl does not establish a new PDF edition.

## TDS, SDS and batch-specific documents

A TDS and a safety data sheet answer different questions. ECHA describes an SDS as information about chemical properties, hazards and measures for handling, emergencies, exposure control and disposal. That hazard-communication role is distinct from a bond-strength table or processing window. Neither title makes one document a substitute for the other's subject. [ECHA SDS overview](https://echa.europa.eu/safety-data-sheets)

A certificate of analysis can report batch-specific results; a certificate of conformity attests against identified requirements. A general TDS may supply supporting technical context without being either document. The distinction concerns what the document claims about which population, not whether it has a polished layout or a signature.

## Processing information and actual outcomes

Recommended processing ranges describe conditions relevant to obtaining performance, not proof that a particular part experienced them. Oven setpoint, material temperature, dwell time and thermal history can be different quantities. Likewise, working time, fixture time and full cure represent different stages rather than interchangeable deadlines.

The resulting product or joint also depends on preparation, geometry and the actual application conditions. This is explanatory synthesis of the manufacturer examples above: the sheets make useful claims within stated boundaries, while finished-part performance remains a different evidential question. A value can be accurate in its test context yet insufficient for a broader service claim.

Sources were reviewed on **2026-11-02 PST**. The 3M and Henkel dates are printed in the cited PDFs. Nicrobraz's identified year is its printed copyright; the filename's month is not independently treated as a revision date. No manufacturer-family equivalence or current-edition claim is inferred beyond the cited document.

## Related reference

[Safety data sheets](./safety-data-sheets.md) · [Certificates of conformity](./certificates-of-conformity.md)