When most investors hear "Williams," scandal-tarred energy behemoth, The Williams Companies (NYSE:WMB) probably pops to mind. But some investors may know a much smaller Williams: construction company Williams Industries (NASDAQ:WMSI).

The latter Williams has also been in the news in recent months, but in a good way. It recently won bids to help build the Springfield, Va., highway interchange, which has been under perpetual construction, and to erect a span of the replacement Woodrow Wilson Bridge.

For years, each of these construction projects has been a traffic bottleneck for the nation's capital. So, any company involved in getting traffic moving again can count on both positive press coverage and a boost in its stock price. And Williams has certainly benefited. Its stock price is up 72% over its 52-week low of $3.01.

Even so, the stock is volatile. In the two years I've followed the company, its stock has swung from $3 to $9 to $3 to Friday's close of $5.17. And, as I expected, Friday's fiscal second-quarter earnings announcement sent the stock down yet again.

Despite revenues rising 1.9%, Williams' second-quarter loss increased by 5.9%. Conversely, for the first half of the year, revenues declined 4% and losses declined by 25%. (One is tempted to conclude that the less business the company does, the better.)

As usual, for this mostly family-owned company, Williams was straightforward with shareholders about its troubles, attributing its poor performance to worsening gross margins in its manufacturing division -- historically one of its most profitable.

The decline in margins was largely because of increasing steel prices. While many people hoped President Bush's repeal of tariffs on imported steel would lower costs for steel users such as Williams, the rise in the euro's value has in large part negated any price advantages. Moreover, Williams says that some of its domestic steel suppliers are refusing to honor their contractual obligations to provide steel at agreed prices.

Company President Frank Williams, III, even went so far as to warn, in the earnings announcement, that the increased price of steel might force Williams to decline its award of the Springfield interchange project. It was that contract which sparked the most recent rise in Williams' stock price.

The risk of that project's loss caused Williams to take a 30% tumble in afternoon trading today.

Fool contributor Rich Smith owns shares in Williams Industries, but none in The Williams Companies. The Fool has a disclosure policy .