LAKESIDE, Calif. -- The next time Mr. Fixit promises a turnaround of two weeks, you might want to get it in writing. In the optical calibration and repair industry, however, recent customer complaints indicate that even a written contract may not help. Jack Voas, principal engineer at Boeing Co.'s Military Transport Aircraft C-17 Div. in Long Beach, said that sometimes much of his light-measurement equipment is highly specialized and there is only one instrument available to do the job. Therefore, he can't afford a lot of downtime. As photonics manufacturers merge and expand, their calibration and repair customers often say they find themselves in a muddle of politics and paperwork. Instrumentation sent back to the OEM for service isn't returned for months. In many cases, that can mean a production-line slowdown -- or even a loss of sales. Jack Voas, principal engineer at Boeing Co.'s Military Transport Aircraft C-17 Div. in Long Beach, said that sometimes much of his light-measurement equipment is highly specialized and there is only one instrument available to do the job. Therefore, he can't afford a lot of downtime. Similarly, Don Myers, senior logistics engineer at GDE Systems of San Diego, said he had a calibration schedule for his light sources and mirror assemblies mapped out from one vendor for a year, but he still received nothing back on schedule. To solve these problems, many customers are turning to alternative sources for their service requirements. Myers was referred to Opto-Cal Inc., a firm that specializes in optical calibration and measurement services, and which recently teamed with Palentronix to offer electronic repair services as well. He said Opto-Cal was able to do all the new work and get his old calibration schedule back on track in 11/2 months. Voas said he doesn't send any equipment back to the OEM any longer, not just because of time problems, but also because of the cost. "They don't take it competitively," he said. Other users agreed that as specialists such as Opto-Cal grow, their customers could experience some of the same delays encountered with OEM service. Until then, however, these firms provide a new brand of calibration and repair solutions for those frustrated with their OEM's service -- or lack thereof.