The time to catch an obsolete specification is during contract review, before there are commitmemnts to material and or sunk costs of material, production and inspection.

Not to mention the cost of scrapping out the production and starting a “Do Over.”

If you get iot right the first time, you don't need a "Do Over."
If you get it right the first time, you don’t need a “Do Over.”

There were over 19,116 cancelled or superceded specifications, commercial item descriptions and standards when I first prepared my list of Obsolete Federal Specifications for cold finished steel in 2004.

These specifications, standards and descriptions often specify mandatory product attributes. Sometimes the replacement standard or specification contain different product requirements.

If you placed your order to the obsolete specification, and the material is in fact delivered to the applicable requirements of the superceding specification, the failure to achieve certain attributes or properties may require a “do over” with new material ordered and a second production campaign. Or a painful engineering change/ waiver from your customer.

It is essential that someone on your team be the standard and specification expert, so you can avoid the waste and stress and expens of a needless “do over.”
Here is my list of obsolete specs that I continue to encounter in the steel bar business :

  • QQ-S-624 Steel Bar Alloy Hot Rolled and Cold Finished General Purpose
  • QQ-S-630A Steel Bar Carbon Hot Rolled Merchant Quality
  • QQ-S-631A Steel Bar Carbon Hot Rolled Special Quality
  • QQ-S-633 Steel Bars Carbon Cold Finish and Hot Rolled General Purpose
  • QQ-S-634 Steel Bars Carbon Cold Finish Standard Quality
  • QQ-S-637 Steel Bar Carbon Cold Finish Standard Quality
  • QQ-S-764 Steel Bar Corrosion Resisting Free Machining

See details for obsolescence dates and replacement specifactions for these in the chart below.

ASTM A 331-95 was cancelled on June 1, 2004. Its requirements were rolled into ASTM A 108. ASTM A331 had been the replacement for QQ-S-624.

obsolete specs copy

To read my original Production Machining  Magazine Article on Obsolete Federal Specifications click here. It contains a couple of links to some helpful sites that may help you determine a specification’s status.

Of course PMPA members have access to their own standard and specification experts through PMPA listserves and staff. A request for an assist always results in a prompt response from the appropriate supplier expert or an answer from PMPA Staff. Where do you go for an assist when wierd, strange, and unusual specifications appear in a quote package?

Do over

Why doesn’t the cost of these correlate to the investment needed to produce them?

Bread= $3.80/pound.
Cold drawn bars for machining right now ~$0.66-68/pound.

This great question came from a discussion I had with Ronnie Masliansky, General Manager, Marketing and Product Control, Arcelor Mittal Steel.

Arecelor Mittal Long Carbon North America is a PMPA Technical Member.

So why do you think that the price of these items doesn’t correlate with the investment needed to produce them?

On hot rolled bars to be cold drawn, the dark oxide surface is called scale.

What we see on the surface is "scale"- a combination of oxides of iron.

Scale is the name given to the oxides of iron that are formed on as wrought products as a result of mill operations (high temperature rolling or furnace treatment)

Rust is the commonly used term for iron oxide from weathering or corrosion.

Scale is

  • Hard
  • Brittle
  • High Coefficient of Friction

So we need to get it off the steel if you are to have any chance of keeping the tool edge sharp.

There are 3  oxides of iron:

Hematite   ( Fe2 O3)  has a microhardness of  ~ 1030 D.P.H., is red  in color, and is not soluble in acid.

Magnetite  (Fe3O4)  has a microhardness of  ~ 420-500 D.P.H., is black in color, and is not soluble in acid. 

Wustite  (FeO) has a microhardness of  ~ 270 -350 D.P.H., is blueish in color, and is soluble in acid. Wustite is the phase that makes up the innermost scale on the bars or rods.

Hematite and Magnetite make up the outer layers of the scale, and due to their composition, make up the larger mass of scale present. Due to their hardness and quantity they are the real dealbreakers for machining as they create tool edge wear.

One of the ways that Cold Finished Steel bars aid machinability is  by removing these hard abrasive oxides from the workpiece, so that they don’t destroy your tools and contaminate your cutting fluids.

Bar Coils