On Call Welcome again to On Call, The Register’s Friday column in which we take great delight in telling your tech support stories – mostly the ones involving bizarre behavior and heroic fixes.

This week, meet a reader we’ll Regomize as "Wilson" who once worked as the boss of a welding shop attached to an engineering consultancy.

Wilson set the scene by telling us this story came from the early 1980s, when AutoCAD was replacing drawing boards.

"We had a new structural engineer who those of us in the shop quickly identified as an idiot with a degree," Wilson wrote.

One day, said idiot decided that the computers used to run AutoCAD needed to be cleaned and that the welding shop was the place to do the job.

"After opening them up on a steel plate work platform, with high amperage welding being done on the other side of the same table, he took an air hose to blow out the dirt," Wilson wrote, before explaining that the compressed air used in welding shops contains some extra ingredients.

"It’s at 90 PSI and is 80 percent air, 15 percent water, and 5 percent oil," Wilson said. "When he hit the boxes with this mess, he blew memory chips and any other loose bits completely out of the motherboards."

• Help desk read irrelevant script, so techies found and fixed their own problem
• User found two reasons – both of them wrong – to dispute tech support’s diagnosis
• User insisted their screen was blank, until admitting it wasn’t
• Vendor’s secret ‘fix’ made critical app unusable during business hours

Despite the obvious damage, the idiotic engineer kept going.

"He wasn’t happy with doing just one PC, he ‘cleaned’ them all," Wilson wrote. "It was great fun watching him try cleaning all the steel grinding dust and dirt off the loose parts after picking them up from the floor, using the fab table and a rag soaked in acetone."

None of the five computers the engineer cleaned survived the process, necessitating replacements.

"Lots of work-in-progress engineering files were lost and the senior engineer was ready to kill him," Wilson said.

The company let the idiotic engineer go a couple of months later for deleting AutoCAD from his computer to make room on its hard drive for a game.

Last Wilson heard, he was employed by a large US-based aircraft company.

Have you seen dilettantes destroy tech? If so, click here – gently – to send On Call an email so we can share your tales of destruction on a future Friday. ®