Fortunately, computer-aided design (CAD) is a recognized tool in the electrical industry. Until recently, architects, contractors, and engineers have exchanged electronic files for coordinating the architectural, structural, civil, mechanical, electrical, plumbing, and fire protection systems. However, a good thing never lasts for long.

More often, architects refuse to issue CAD files to subcontractors, delaying project scheduling and impairing coordination efforts, while denying clients the opportunity to receive as-built drawings on electronic media. Our industry must address this growing problem and get back to business with CAD.

It seems progressive contractors are penalized for implementing computer technology in their businesses. Architects expect contractors to bear the cost of electronically scanning or digitizing blueprint drawings to convert hard copy media to electronic media. Scanning creates an inaccurately scaled image file. Digitized drawings (.dwg) are to scale; however, they take an average five days for completion. They’re also $200 per D-size sheet. Furthermore, you can’t include these costs in a competitive bid, and project scheduling doesn’t allow sufficient turnaround time for this conversion process. Surely manual drafting isn’t the solution.

The majority of blueprints issued are produced from original vellum drawings plotted from CAD stations. If blueprints and CAD files are one in the same, they should be issued with the same frequency and guidelines.

If unethical altering is a real concern, we need to consider discontinuing the use of erasers, white out, copy machines, and yes—even pencils. One solution may be to issue the architects and engineers a disclaimer form, waiving liability of the issuance of electronic files. Yet, many firms still refuse to issue CAD files.

We have all this technology and nowhere to go. Architects, let us reopen the information highway and get back to business, with CAD.

Brockton Knowles
CAD Manager, Bergelectric Corp.
Los Angeles, Calif.

Vacuuming Dirt Out

I enjoyed your article in the September, 1998 issue, “Maintaining The Bottom Line.” However, there is one correction I would like to point out. In the second sentence under Motor Controls, the author writes: “blow out dirt weekly.” You should never use compressed air to blow dirt out of electrical equipment. You could cause more problems by blowing fine dust particles that could settle on contactors, relays, coils, inside circuit breakers, etc.—basically cleaning the outside and contaminating the inside. If dirt is a problem, you should de-energize the control equipment, and vacuum it out.

Rudy H. Matthaei, P.E.
TU Services
Dallas, Texas