Navigator #12, August 2002

Rapid Tooling

Vista Technologies has officially opened its Rapid Tooling Center for business. Vista can now get you spec material parts, FAST! The Rapid Tooling Center is using high-speed milling for injection plastic mold making. Lead times as fast as 7 days, but consistently within 2-4 weeks. Vista has already completed successfully over 100 molds during the last year.


The high-speed milling center is very accurate and fast. This demo was cut in less than ten minutes with the accuracy to produce a .005” wall thickness for the entire border.


This is a two-shot, over mold application. First, the blue sizers were injection molded over the nitinol rods, and then the white handles were over-molded onto the nitinol rods with the attached sizer. This was a seventeen-mold project, with first parts being shot in nine calendar days.

With high speed machining, Vista can cut mold halves faster, more precise, and with a better surface finish than conventional tooling. The high-speed mill is a Mikron 700. It runs at 42,000 RPM’s, without any coolant. The tolerancing of the machine is .0002”, which is the most accurate method of any rapid prototyping equipment used for rapid tooling.

Vista is cutting 7075 Aluminum for its mold inserts. There are several benefits to using aluminum for the mold inserts. First, the cost in material is cheaper than tool steel, the aluminum machines up about twice as fast as tool steel, and the molds can run without coolant lines because the aluminum dissipates the heat well at the press. All these features save time and money.

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This impeller mold shows the complexity that can be achieved with high-speed machining. Aluminum tooling and high-speed machining allows for the creation of inserts and deep pulls that were not available in the past. There was no EDM work done to this mold.


Above is another example of a mold with a hand pick-out.
This hand pick-out allowed the undercut feature to be molded. These plastic parts were supplied to the customer in less than two weeks.

Aluminum tools are great for filling the niche of low volume, spec material parts. The quantities can vary from 2,000 to 10,000 parts due to the geometry and material required. Even though we can produce much higher quantities, most of our customers are just looking for 50 –100 parts.

Rapid Tooling is becoming a new norm for the industry. Companies need spec material parts faster for specific testing like UL and drop testing. Rapid Tooling has only become available in the last 2-3 years due to technology in equipment, software, and progressive thinking by a few individuals.

Aluminum molds are preferred over sintered molds, because there are no secondary operations on the tools, they have better accuracy, and hold tighter tolerance. Prototype aluminum tools are also preferred over conventional tooling, because they do not add the extra step of machining the electrode and E.D.M.ing of the mold insert. Aluminum tools can be modified over and over. These tools can be welded up, inserted, and re-machined with ease. This will eliminate the cost of remaking entire molds along with the lost time.

Quick Quip "Luck is what happens when preparation meets opportunity" -ELMER LETTERMAN