'Saw' Trap Builder Recalls The Most Gruesome (And Funniest) Traps

'They probably unloaded enough blood for 10 human bodies,' Jason Ehl tells MTV News of one especially bloody death.

With a cool $24.2 million opening weekend, fans of the storied "Saw" franchise celebrated the final installment, "Saw 3D," by getting to theaters and making it the #1 movie at the box office. The final chapter topped "Saw VI," which earned a modest $14 million its opening weekend, but finished fifth overall in the franchise's opening records.

Given the fact that the seventh film is likely the last, MTV News sought out one of the unsung heroes of the "Saw" series — trap builder/ engineer extraordinaire Jason Ehl — to talk barrels of blood, reveal a few of his "greatest hits" and find out why three of the films' directors refer to him as a "mad scientist."

MTV: What was your filmography leading up to "Saw"?

Jason Ehl: It's funny, because the first year I did "Saw," I just came off of "Thomas the Tank Engine" and [TV's] "RoboCop." ... I came from family, sort of G-rated stuff, and then the very next day, you would be coming home and then having to clean all the blood off your clothes. It was a wacky mix of models and miniatures and all that kind of stuff ... [but there] was really nothing comparable to "Saw" before we started "Saw."

MTV: What intrigued you initially about the "Saw" films?

Ehl: I started on "Saw II," and there were two things I worked on: the puppets and the reverse bear trap. To be honest, I hadn't seen the first "Saw" movie. I just got a call from one of my regular clients about this kind of cool movie that's come to town and "Would you like to do a few things on it?" It was after that build that the intrigue started, because it was, with my engineering background, the best job you could ever expect. It's in the movie industry and you get to sort of make cool little machines. When I was a kid, I used to — do you remember Mouse Trap? I've never played a game of Mouse Trap, but I played with Mouse Trap ... so essentially, to me, "Saw" is like Mouse Trap.

MTV: How many calculations are involved in designing the traps and whether humans can survive them?

Ehl: On paper or on the books and stuff like that, all the traps kind of started like that. Like, if we refer to one of the movies that just came out, one of the more heavily engineered traps would be the very opening trap, and it started out as a single saw, and then based on the changes and story development, it turned into what you see on film. The reason why it was heavily engineered [was] to keep up with the schedule that had to be built when the change happened. You have to engineer on top of what already exists to make what we want to happen rather than just engineering on a flat paper starting from scratch. There's that, which I would say is the extreme case, and then there's when we're on sets, "Wouldn't it be great if this happened? And, by the way, it plays tomorrow morning." So paper and trying to calculate it doesn't fly, and it's a matter of going back to the shot at midnight and hoping something will make it happen.

MTV: What have been some of the most challenging or interesting traps to build?

Ehl: On the last one, we had some big ones, such as the rail car. The challenging part, a lot of the times, comes from a lot of the departments [working] independently, and then all their bits in the 11th hour have to come together and then hopefully work together. So that one was a bit of a challenge in the sense that I couldn't build everything in-house. We kept it there and then brought it to set and made it go. It was the matter of, this has to go to a trained yard and work with whatever is existing there. ... I would say the most challenging ones were when everyone and multiple departments have to come together and make it all happen in a short period of time.

MTV: Any other examples?

Ehl: Also in "Saw 3D," the throat-puncturing trap. That was me, prosthetics and the carpenters department. That one went through a lot of changes along the way. The only thing that you can count on, there will be a lot of changes, but the due date never changes. Everyone has to keep up with the due date and keep up with what everyone else is doing so that their thing locks into my thing, which works with someone else's thing. The most challenging thing to do — less from a mechanical point of view and more of a logistical point of view — when things are happening so quickly.

MTV: Are you ever surprised at what traps people come up with? Do you have a favorite?

Ehl: This last round, my favorite was probably that throat one, because it was an elegant setup. The mechanical bits were nice and simple, and it has a nice blend of some mechanical engineering, some electrical engineering. The other thing that I remember, back to traps and how pleasant they are and how hard they are, is just the time on set. The actor was great, took one for the team and would sit in the trap for hours and everyone was just pleasant and just moved along and got it done.

MTV: Are you surprised by how gruesome it gets, or are you so totally desensitized that the traps make you chuckle?

Ehl: [Laughs.] The triple saw trap at the beginning [of "Saw 3D"], the effects team had gone through three 5-gallon pails before we even got halfway through, and someone was like, "Do you know how much blood is in the human body?" We're at a few pints here and there. When you walked across the floor, everything was red and everyone's shoes. That's why I laugh, because all I remember is, our feet were sticking to the floor like you were in the oldest movie theater you have ever been in, and you stay too long and you're, like, glued to the floor.

MTV: So on that one, did you use more blood than is actually in the human body?

Ehl: Oh, yeah! Big time! On that one, that was for visual effects, and it was just crazy. They probably unloaded enough blood for 10 human bodies. One trap, the meat-scale one, one [actor] said he had to lay in his blood for a day, and he actually got glued to the floor. When we peeled him up, it peeled the paint off the floor. He was stuck there. [Laughs.] So that's how I see the "Saw" movies as far as scary. It's just stuff like that when you're on set and see an actor stuck to the floor.

MTV: How much do you pay attention to putting someone in a trap and having it work the way it's portrayed?

Ehl: The buildup of building the trap is a lot of that. I know [production designer] Tony [Ianni] would spend hours researching whether or not this would do what it's supposed to do. They would call in experts from whatever fields. Like when they were going to electrocute the person in the bathtub, they called in an electrical engineer and said, "Would this happen? And if it wouldn't, how would you recommend this should be?" Kind of so it would be realistic. Doctors, engineers, all that kind of stuff are referenced in. Just Internet galore, looking up references to industrial accidents and actual stats and things like on the blood amount to make things seem realistic. Like the one with the saw that we talked about was for sheer spectacle. The reality of that one was blown out of proportion.

MTV: What was the most painful or gruesome trap?

Ehl: The hair-pulling trap was pretty gruesome. When we're trying a fresh trap, I would go on the Internet and read what people like and would write. There was this thing with the best "Saw" traps ever, and the ones that people really chime in on are almost like the simplest ones, like the needle pit, which from a trap point of view is the simplest it gets. For the prop guys, there were thousands and thousands of needles that needed to be made, but really, it's the simplest concept. The trap where the lady put her arms in the glass closure and her wrist gets cut when she tries to get her wrists out. But the hair one, it was built simple. Just a whole bunch of spinning wheels and elements, and it was pretty gruesome.

Check out everything we've got on "Saw 3D."

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