I couldn’t have picked a better episode to chat with property master Craig Grant. Grant, who has been working on Murdoch Mysteries since its first season, is the dude who creates and builds all of the funky things featured on the CBC drama. During Monday’s “High Voltage,” he manufactured everything from Thomas Edison Jr.’s Vital Motion Plus–the episode’s deadly weapon–to the robotic arm, that odd, nose-plug contraption and the electric wheelchair (who else caught Grant’s cameo as the driver of that wheelchair?).

Turns out Edison Jr. really did use his famous father’s name to sell weird items to folks back in the day, including the items featured during Monday’s instalment. We got Grant on the phone to chat about his gig and an intriguing storyline about Brackenreid’s painting.

Let’s use Monday’s episode, “High Voltage,” as an example of a week in your work life. How far in advance do you get a look at a script and know what you have to manufacture?
Craig Grant: It’s a hard question to answer. Technically, we get the script two weeks in advance. We shoot 13 days per block–two episodes per block–and we usually get the scripts for the next block at the end of the two weeks. So, the next day we meet the new director and have concept meetings. Because of some of the things that I need to procure, the writers usually sneak down to my office and give me a little, ‘Hey, we might need this!’ or ‘We might be doing that.’ Technically I get them two weeks in advance. Realistically it can be a couple weeks to a month in advance.

‘High Voltage’ was written by Carol Hay, so she had told me early on that she was writing this episode about Thomas Edison Jr. and one of the reference photos we had was this wacky medical device that Edison Jr. had flogged. At the Edison booth, there was this guy with a leather pad on his chest and in another scene he had this weird contraption on his head and in his nose. Those we built based on photos based on a real Edison device. I found photos of those and–because they were leather and I’m not a sewer–I took them to a shop to have them built. They weren’t functional but they were identical to the real Edison devices that we had in the day. With Edison Sr.–people used to see the name Thomas Edison and think it was him and would send the pieces back to him because they didn’t work–he would send letters to them saying, ‘It wasn’t me.’

So all of that part of the storyline was true.
Right down to Edison forcing his son to change his name so that he didn’t do that in the future.

Was the Vital Motion Plus an actual item too, or did you create that for the storyline?
That was something that we came up with. And in one of the original scripts it was more of an upright, strap yourself in type of thing, and I thought it would be a lot of fun if we could do a chair because if you could have the springs, it would have that vibrating motion. Make it an electric chair, but make it more fun. The original script had that there were these electrodes attached and I said, ‘When you find the dead body, is it more fun to have him standing up, strapped to something, or slumped over in a chair?’ That was actually a wheelchair that I took apart and modified to end up with the look that we got.

When it comes to turning the wheelchair into a device, does the idea just pop into your head? Do you get any feedback, or are you left to your own creativity?
I’m lucky enough on this show that the powers that be just let me go. I pretty much get to design and build all of the props that you see on the show from the airplane a couple of years ago, to the electric car to this chair with almost no interference. Sometimes there will be a little back and forth, but most of the time I’ll show them what it looks like as it’s being built. It just flows out of me. I can’t draw, so I don’t do sketches or schematics. I will just start building, and I’ll drive around to places like Lee Valley and look at what they’ve got. There were some lovely little brass bits on the chair that I 3-D printed, and other pieces as got as surplus parts that I thought looked like they looked like electrodes. It just kind of comes.

And sometimes they come up with ideas that are better. I was going to mount the control box on the arm of the chair and it was decided that it would be better if it was separate so that you could walk around with it. It’s a collaboration.

You mentioned a 3-D printer. Are you using that technology a lot now?
I built a 3-D printer between seasons 7 and 8 and started to learn how to use it. The first thing I was building for myself was a life-sized human robot. Just because I could. In ‘High Voltage,’ as we move down the block, you end up at the prosthetics booth. The arm that is in front of them, moving up and down, was 3-D printed and it has six or seven servo-motors inside it. I was off-camera, operating that by remote control. That was just something I happened to build in the off-season and then when they were writing the episode they said, ‘It would be great to have a robotic arm.’ I said, ‘I’ve got one guys.’ I reprinted parts in black so that they looked like cast-iron, added brass and wrapped the arm in leather and put a glove on it. I hope you can’t tell that it was 3-D printed, but it was an incredibly high-tech piece.

I was the guy driving the electric wheelchair and that was something from back from Season 1. I told them it would be nice to update it a little bit and see it again in the medical convention and they said it would be nice if it could be driven so I did that. In the shot with the arm moving, I had to drive the length of the hall and as soon as I was out of camera I had to jump out and whip around a corner, grab the remote control and start controlling the arm. It was a little bit of fun sleight of hand. I have printed a number of other items that will be seen in future episodes.

You must have a lot of fun.
I love the show because of the freedom they give me, because of the builds I get to do. That aspect is a lot of fun and there are very few shows that would give a prop guy the freedom that I have here. On the other hand, our budgets are tight and manpower is tight. It makes the show harder every year.

Who painted Brackenreid’s painting?
Brackenreid’s painting will figure heavily in an upcoming episode. We have a whole episode around Brackenreid and Tom Thomson. It’s a really funny little bit between Brackenreid, Ogden and Tom Thomson.

Our scenic painters painted that piece and they did a whole bunch of versions of it. We ended up needing four copies of it. In the very first episode he was painting it at his house and if you watch the episodes carefully it has progressed. More has been added to it and we end up with a finished product.

We’ve talked about the big-ticket items that you build, but what about the small stuff? Are you responsible for everything from the medical stuff in Emily’s morgue to, say, the ledger at the Windsor House Hotel?
Yeah, a prop is anything they handle. Now, I get the ledger and then I talk to our graphics department and tell them I need 20 pages that we can flip through and need stuff written on the pages. We have a graphics guy who will do the graphics or depending on what is required and our timing sometimes we’ll do the graphics. I have a guy I work closely with named Steve that does all of Murdoch’s handwriting on the blackboard. He’s always there and Yannick doesn’t really have the time to write that stuff, so we do it. In the morgue, I do all of the bodies and the body parts and all of the instrumentation. All of those things fall under my domain as well.

Murdoch Mysteries airs Mondays at 8 p.m. on CBC.