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"There's a light, over at the Frankenstein Place . . . ”

Some of you might recognize that line from The Rocky Horror Picture Show. Brad and Janet saw that there were lights at the home of Dr. Frank-N-Furter and were given hope that there would be some relief from their troubles. It was literally the light at the end of the tunnel. Little did they realize – as the cliché goes – that the light was just the beginning of their troubles.

Well, there's been a lot of jawboning from the feds, and other sources, that the leading economic indicators are showing there's a light at the end of the tunnel of our economic woes.

According to a ThomasNet report by David R. Butcher, "Orders for durable goods rebounded sharply in July, representing their biggest gain in two years. Demand for motor vehicles alone rose 0.9 percent, on the back of the government's CARS program.

Manufacturers' orders for durable goods rose 4.9 percent last month to a seasonally adjusted $168.4 billion, the United States Department of Commerce reports today. That was the third increase in the last four months and the largest since the 5.4 percent bump in July 2007."

Sounds like the downhill slide has slowed and may have hit bottom, so we may be back on the upside of the economic growth curve. Keep your fingers crossed that the light at the end of the tunnel isn't an oncoming train.

• • •
It's time for a case history.

The Clean Plate Club

Machining a large polycarbonate plate wasn’t the problem for this shop, it was how to hold it in place. Taping it down worked, but entailed after-work cleaning. Then the shop found the answer in a vacuum.

What do teenagers know? Sometimes quite a bit. Two teens – best friends Carlos Barrientos and Lino Covarrubias – had an interest in machining and decided to turn it into careers. They began their own business, and today, with 30 years of machining experience between them, own Motiv Design Group, Inc., in San Jose, CA.

“We knew how we wanted to run our business and we are proud that we are still running it the way we want,” Barrientos said.

As with many start-up shops, there is the desire to own every piece of equipment available. Realizing it is easy to get overly equipped and deep into debt, the two co-owners were careful to buy only the machines and tools that would keep them competitive and benefit their shop’s bottom line.

During their experience, they learned what would work for their business and what would not. They had experience with CNC mills, so they purchased a CNC lathe to make their business more competitive.

“We learned that the best way to go was to keep work in-house,” Covarrubias said.

Soon after they bought the lathe, they purchased a CNC horizontal milling machine to expand their shops capabilities and respond to customer demands. They realized that the worst reply they could make to a request for a quote was not to bid because they didn’t have the capability to do the work.

Besides the machine tools, the duo realized that an integral part of their capability was proper workholding. For their work, they chose the Mitee Bite VacMagic vacuum chuck.

Going to Tape
Before buying the vacuum chuck, they tried different hold-down methods, such as tape-down, thinking that a vacuum chuck would cost too much, considering the extra investment needed in a compressor or pump. They knew a vacuum chuck would be the ideal solution, but they considered the investment too daunting.

The VacMagic workholding system allows pieces to be held for machining without the use of clamps

One of Motiv Design’s continuing orders was for one of its major customers and involved tooling a 3/16"-thick, 18½"×27½" polycarbonate window. Quality was a major priority. Using the tape-down method to hold the piece for machining caused problems. It required applying alcohol to the tape – which would get on the part as well – using a scraping tool to remove the piece from the work table, then removing the protective paper which had tape stuck to it, and reapplying a new protective paper.

If the alcohol smudged the window, they needed to wipe it clean. Sometimes they would scratch the polycarbonate while trying to pry the piece from the work table, reducing it to scrap.

The use of tape wasn’t as inexpensive as they thought at first, since it involved purchasing the two-sided tape, alcohol, and protective paper.

Where Motiv Design once had to use double-sided tape – and the mess involved with its use – it now uses a vacuum workholding system to keep polycarbonate workpieces stable during machining

A visit to a machine tool distributor during an open house familiarized Barrientos and Covarrubias with VacMagic’s vacuum holding system and convinced them it was the way to go. With the next order of the polycarbonate windows, they purchased the system. Their biggest concern was the system’s ability to hold the 20"×30" subplate.

“I spoke to tech support at the company and they suggested a few ideas about how to make it work,” Barrientos said. “But, they told me our needs might be beyond the limits of the system.”

Customization
Working with technical support from Mitee Bite, Center Ossipee, NH, they made their own subplate out of ¾" thick aluminum, following the specs for hole locations and slot locations. They planned to use the rubber gasket that came with the VacMagic, but it didn’t fit the perimeter of the plate, but to their surprise, the vacuum held the material while cutting without the gasket. They used pins to position the material in place and then remove them once the vacuum seal is established. The VacMagic holds both the subplate and the material. The vacuum workholding system works without the gasket.

Compared to using double-sided tape and all that entails, using the vacuum workholding system is cost-free after the initial investment.

The system made the job easier, cleaner, and faster. One area where they gained efficiency was not having to take the time to let the alcohol soak the double-sided tape to make it easier to remove, then cleaning the subplate of tape and alcohol. It’s about 90 percent faster to remove a finished part and load a new piece of material.

With the tape-down method, the finished part was removed from the machine, and then placed where the tape wouldn’t stick to anything. It required a lot of table space to keep parts from touching and sticking when there wasn’t time to peel off the old protective paper and apply new protective paper.

Carlos Barrientos [right] and Lino Covarrubias were teens when they opened their shop, Motiv Design

Carlos Barrientos (right) and Lino Covarrubias were teens when they opened their shop, Motiv Design

Now that tape is no longer used, parts can be stacked on top of each other without worry. Also, there is much less part scrap since completed parts don’t have to be pried off the work table which resulted in occasional scratches, ruining the piece. Original protective paper stays on the piece from the start until the customer removes it, insuring there are no scratches, fingerprints, or smudges on their parts.

The VacMagic system resulted in about a 40 percent savings for the job. Not only has it made the work more profitable, it lets anyone, no matter what type of experience they have in machining to setup – and run the job. Clamping the VacMagic to the machine table and connecting the air supply is quick and simple.

“The VacMagic paid for itself within a couple orders,” Covarrubias said. “With it we can respond to an RFQ for a part that can’t be clamped in a vice. Though we’ve only used the VacMagic for the one job, we plan to build more fixtures to help speed up production of our aluminum jobs.”
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