J&T Blacksmiths Ltd and William Crawford & Sons, based in adjacent factories, depots and offices in Hillington, near Glasgow, called in administrators after running up debts of about £3 million, much of which is thought to be owed to HMRC.
Administrators Paul Dounis and Ken Pattullo of Begbies Traynor have made 46 staff redundant at the group, owned by the Curran family, which has combined turnover of £5.2m, to allow it to continue trading while a buyer is sought.
Mr Dounis said the group's problems were down to its failure to "react quickly to the lack of contracts available on the marketplace".
He said: "They kept an overhead base that was simply unsustainable.
"If your turnover is falling you need to adjust your overhead base and they simply weren't doing that quickly enough. The parts of the group that were profitable were carrying the parts that weren't."
The administrators, which took control of the business on February 19, are hoping for a quick sale to protect the remaining 42 jobs, and to help the group secure new contracts.
He said "serious interest" had been shown by prospective buyers and confirmed that competitors were keen to take on some of J&T Blacksmiths' key contracts, including a supply deal with ScottishPower.
Blacksmiths, established in 1979, provides steel works including fencing and fabricated staircases to contractors and utility companies. It is understood to have been performing less well than its subsidiary.
William Crawford & Sons works alongside Blacksmiths to allow the group to offer an integrated construction, repair and maintenance service.
Mr Dounis said the administrators had no plans to set a deadline for offers.
Before calling in the administrators, Crawford had employed 21 of the group's staff, 10 of whom have been made redundant. The rest of the staff moved over to Blacksmiths.
Mr Dounis said the group had employed 200 staff in its asbestos removal and surveying arm, which was sold prior to his appointment. He was confident its "solid customer relationships would make the businesses attractive to an acquisitive construction or manufacturing group".