For the original chrome endoskeleton in "The Terminator," "We made a body cast of Arnold Schwarzenegger, poured melted clay into it, pulled out the clay form, sculpted it down to the skeleton form, made a mold from that and so on." On "Salvation," he compares, "We took the 2-D designs and worked them into a 3-D computer modeling program and sculpted it all digitally. It's absolutely faster. We still had to detail the parts by hand to give them that gritty, nasty look but it took months out of the process."
The T-800 makes a cameo appearance in the film, based on existing digital scans of the current governor of California that ILM integrated into the movie. Schwarzenegger signed off on it, once McG convinced him he wouldn't have to take time away from his day job.
Rosengrant built various types of Terminator, including several versions of the T-600, which as the primitive predecessor to the T-800 is "bigger, more Neanderthal and bulky but still very lethal and menacing," he says. No wonder nine-year-old Jadagrace said the model "freaked me out" It was a 7'4" fully articulated combination of rod puppet and radio-controlled animatronics with a moving head, eyes and limbs. It was featured prominently in many scenes, although the T-600 seen where Marcus first appears is actor Brian Steele in a body suit.
Rosengrant also created 1,400-pound (635-kilogram) T-1s and the Hydro-Bots, which he describes as a cross between "a psychotic crab and a deep sea fish with an eel body. It was a combination of animatronics and CGI, and we used air-driven pneumatic cables. It had to work in water, so everything had to be waterproof." He created two full Hydro-Bot models, other bits and pieces, and one that could ram through a helicopter. "That one was made from steel."
A scene where a writhing Hydro-Bot is examined on a table features a cameo appearance by Rosengrant as "the guy wrestling it." He did so with rods painted blue, which were digitally removed later on.
Not all the machines featured were computer generated, however. See which character played both man and machine in the next section.