Exciting applications, improved hardware unveiled at SPE thermoforming show.

Thermoforming's key role in the world's first all-plastics car was among the biggest news for the record crowd of nearly 1300 that attended the 8th annual SPE Thermoforming Conference and Exhibition, held in September in Nashville, Tenn. Plenty of new equipment was also on hand there, including pressure-forming machines, a servo-actuated plug assist, and a new pressure box that is adjustable both in length and width to accommodate a range of mold sizes. Also new are a zoned gas-catalytic heater panel and a U.S. source for halogen heating elements. New CAD/CAM software for CNC trimmer/routers was also on display

Thermoformed car body

A thermoformed chassis and body panels will be featured on the world's first all-plastic car, which is due to go into commercial production in January. The parts are being made initially in the U.S. for assembly in China. The four-door, five-passenger Paradigm car will weigh less than 2000 lb. Automotive Design & Composites (ADC) Inc. of San Antonio, Texas, designed the vehicle to have body panels and trunk formed from co-extruded sheet of ABS with an ASA cap layer that will hang on a pultruded composite frame. The body panels are being formed by MultiPlastics Corp., Mt. Pleasant, S.C., using a 8 x 16 ft rotary machine from Maac Machinery, Itasca, Ill.

The chassis will be made from a 1/4-in. sheet of either ABS or TPO vacuum-formed into a tub and reinforced with pultruded fiberglass tubing, says ADC president Michael Van Steenburg. The hood and other parts may be made from a 20-mm-thick sandwich of thermoformed PPO-alloy skins, glass fabric infused with thermosetting vinyl ester, and a urethane foam core. The bumper and front fascia will be thermoformed from a polyolefin elastomer sheet with a uv-resistant cap layer of DuPont's Tedlar PVF film. The dash and inner console will be thermoformed from soft vinyl over ABS.

Four prototype cars will be made for evaluation, and then China's Huatong Motors will assemble 5000 units at its Sichuan plant in the first year.

Plug assist goes servo

Three firms have introduced servo-actuated plug assist, which they say provides better control than pneumatic or hydraulic motion. Unlike fixed plugs, servo-actuated plugs can also be pulled back during the forming cycle in order to enhance cooling.

Lyle Industries Inc., Beaverton, Mich., offers servo plug assist on its entire FM series of machines. Servo drive allows the full toggle clamp tonnage to be used in holding the sheet in place, so no slippage occurs.

Servo-driven, up-acting plugs are offered on the updated V5.0 trim-in-place roll-fed machine from International Thermoforming Systems (formerly Irwin International) in Yakima, Wash. A patent-pending linear ball screw drive is said to provide more accurate plug-speed control than a crank or toggle mechanism. The redesigned platen accommodates a 52 in.-square tool (vs. 50 in. square previously).

Servo plug assist is part of the new KMD 52 B automatic punch-and-stack pressure former from Kiefel Technologies, Hampton, N.H. It has a 520 x 400 mm forming area and speed of up to 50 cycles/min. A new arrangement of heating elements reportedly improves efficiency by 15%. A new servo punching table fitted with draw spindles is said to yield higher cutting quality. And the new chain-rail system is internally cooled. Also new are a servo-driven stacker, quick-tool-change package (changeovers in 10-20 min), and a control panel that slides on a rail from station to station.

New cut-sheet machines

A new side-by-side pressure former from American Plastics Machinery Corp., Great Bend, Kan., is the largest double ender in the firm's Prime Choice line. The 4 x 6 ft model features a new load/unload station and optional top-mounted moving heaters that follow the sheet into the forming station before withdrawing.

Also new is the first single-station cut-sheet machine from Monark Equipment Technologies Co., Auburn, Mich. It is designed to form pre-printed or tight-tolerance parts. The new SV model has a single top oven with 40 ceramic heaters. The oven moves vertically up to 36 in. The 2 x 2 ft forming station has a fixed clamp frame and moving bottom platen that travels up to 14 in. on a four-post linear guide system. The machine handles sheet up to 60 mil thick and costs $65,000.

Also new from Monark is its first all-electric four-station rotary unit. Monark's rotaries previously all had three stations as well as hydraulic and pneumatic power. On the new model, an Allen-Bradley PLC controls AC variable-speed motors for indexing and platen movements. The result is said to be faster set-up and better control. Forming area ranges from 4 x 8 to 8 x 12 ft. Prices start at $300,000.

New and hot

Although gas-catalytic heating may save energy costs, zoned heating can be more costly to achieve than with electric ovens. A less expensive route to zoned gas heating is to create zones within one catalytic heater element, says American Catalytic Technologies, Branford, Conn. Its new Multi-Zone gas-catalytic heater costs up to 50% less than using a series of individual heaters. MultiZone heaters consist of a single large heater with a common preheat element. The unit is baffled internally, creating individually controllable sections within the unit. A separate gas line and feed control is provided for each of the baffled areas. Sized from 12 x 12 to 24 x 72 in., the burners can be custom profiled up to six zones.

American Catalytic also showed its new Electronic Pressure Management System (EPMS), a PLC controlled proportional valve used to regulate gas pressure electronically rather than with manual valves. EPMS adjusts gas flow from 0 to 100%. The values can be entered on a touchscreen or retrieved from memory.

Halogen heating elements, said to provide heat-up times as short as 0.2 sec and temperatures to 2000 F for quicker sheet heating will be offered in the U.S. next year by Ceramicx, an Irish supplier of ceramic and quartz elements. Ceramicx will sell halogen heaters through Steven Benjamin Inc., Springfield, Mass.

Tooling & trimming

The new Universal Pressure box, from Edward D. Segen & Co. Inc., Milford, Conn., allows width-wise adjustment of the pressure box as well as the more common length-wise adjustment. The side panel closest to the heater is water cooled. Model PXU200 can be adjusted from 11 to 20 in. wide and 12 to 23 in. long. Model PXU300 can be adjusted from 15 to 30 in. wide and 15 to 33 in. long. Price starts at $4650.

Save space and apply higher pressure with Segen's new Titan sheet-clamp assembly kit, in which a sealed nitrogen cylinder replaces the usual air cylinder. The nitrogen cylinder is of 0.75-in. diam. and applies 80-psi pressure, while an air cylinder has 2-in. diam. and provides lower pressure. The cylinder's smaller diameter permits closer positioning of the mold base and clamp frame to the oven. Unlike an air cylinder, the nitrogen version requires no plumbing of lines for actuation.

A new Windows-based CNC trimming package upgrade is available for Surfcam CAD/CAM so,ware by Surfware Inc., Westlake Village, Calif. It can be used for three- to five-axis part trimming and costs $2995. A complete Surfcam 2-Axis Plus design package with the trimming program and 3-D wireframe and surface modeling costs $7790, according to Surfcam sales agent Atwood CAM Resources Inc. in Cleveland.

Also new for trimming is a series of off-line roller die cutters from Tabco Products Inc., Pawtucket, R.I.. They come in sizes from 30 x 36 in. to 60 x 48 in.