Making a paper maché kitchen knife
Published October 15th, 2018
I made this paper maché kitchen knife prop to go with one of my evil gingerbread people that I made for Halloween 2018!
I made the basic shape for the knife out of three layers of foam board. I took our biggest kitchen knife and traced it onto foam board, and then drew a slightly more exaggerated shape around that and cut it out. You'll see for the blade portion I only included the back edge of the blade; that way the back edge will be thick, but of course I want the blade edge to be thin.
I traced the handle two more times and cut 'em all out.
I cut out two pieces of poster board to create the edge of the blade. I taped them around the middle piece of foam board, and taped the other two foam board handle pieces in place.
I covered the entire knife handle in very thin strips of masking tape (not shown) to smooth out the edges a bit. I covered the blade with a piece of shipping tape on each side; this is to help prevent the poster board from warping when I add...
Paper maché
I then covered the knife with tiny pieces of paper maché — one layer all over and a couple more at the connection of the blade and the handle. You can read about my paper maché process and materials here. The short version is: I use Roman PRO-543 universal wallpaper adhesive (paid link) and alternating layers of newspaper and brown wrapping paper.
Painting
Before painting, I covered the knife blade in three light coatings of spray gesso (not shown), to smooth out the texture of the paper maché a little bit. I don't use gesso for all my projects, but I do use it when I want a surface to be very smooth. I normally don't mind seeing the subtle texture of the little scraps of paper in most of my projects, but I wanted the knife blade to be as smooth and uniform as I could get it. Anyway, the gesso helped!
When that was dry, I spray painted the whole knife silver and let that set for a day.
I then used a piece of very thin (1/4") masking tape to create a line along the edge of the handle. I protected the blade with newspaper and masking tape, and I spray painted the handle black. I removed the masking tape to reveal the line of silver down the handle.
The masking tape didn't work perfectly (it rarely does) so the line was a little blurry, but I fixed it with some silver and black acrylic paint and a small paintbrush. Even though the masking tape doesn't always work perfectly, it's still great for giving you a very clear guide to work with when finishing your painting by hand. Trying to paint a straight line like this with no guide would be a nightmare!
Oh yeah, I also painted silver dots on the handle.
I then did a very light dusting of black spray paint on the blade, let that set, and then I hand-painted a silver edge along the blade. The dusting of black is there to let this silver edge stand out as even brighter/shinier.
I brushed a coating of clear gloss onto the blade to make it nice and shiny. All done! I'm really happy with how this came out!
I glued the knife into my gingerbread lady's hand with a hot glue gun. Check out my article about my evil gingerbread people for more pics!