The Scottish Fisheries Museum in Anstruther asked Wendy from The Malting House Design Studio to create some interactive exhibits. One of the items was to be a massive floor jigsaw. She wanted to know if I could help and if so, how best to make it.
Wendy wanted to make the jigsaw as large as possible. As my laser cutting bed is 1200 x 800mm, she chose to work with that. She wanted to make the jigsaw chunky and robust. As the laser can cut 9mm thick mdf, ply and Perspex, we discussed the merits of each.
Mdf feels like a jigsaw and cuts well. Thick plywood is less good for cut work. Knots in the laminated layers prevent clean cut throughs as the wood is more dense, and this can ruin a job. Perspex is good for cutting, but edges can be sharp and could hurt children. As the jigsaw needed to be printed with artwork, the decision came down to material properties and printability.
We agreed that mdf was the best material as it could be sprayed white before printing to make sure the colours popped. It would laser cut well, and the pieces would be safe to handle.
Artwork for printing
Wendy planned to create and adapt all the artwork required herself. She had a picture by Jurek Putter for printing onto the jigsaw, and the first step was to print the mdf board at the right size.
I suggested that we should make the mdf board a bit larger than the jigsaw needed to be. An extra 5mm in each direction would making the board 1210 x 810mm. If the edges became scuffed during printing or shipping, if wouldn’t matter. I would laser cut the final shape when I cut the jigsaw pieces so all the edges would look the same.
Wendy arranged to have the image printed a little bigger than 1200 x 800mm with 2 to 3mm bleeds at each edge. This standard printing practice would make sure that the jigsaw would be printed right to the laser cut edges.
Laser cutting a jigsaw
To laser cut the jigsaw, I needed a vector file with lines that the laser would follow to cut each shape.
My top tip for Wendy was to have sets of horizontal and vertical lines that the laser would cut once only. The laser can cut 9mm mdf in one pass. Cutting the same line twice means that the back can be damaged by heat and flaming if the material catches even momentarily. Working this way reduces production time and improves product quality while keeping costs down.
Wendy wanted the jigsaw to contain lots of interesting shapes that were not necessarily fully interlocking. She wanted to have four shapes, a barrel, a cross, a bird and a window incorporated into the design. I agreed that she could have whatever she wanted if she stuck to my vector artwork design tips!
All our careful preparation paid off. Wendy made the outline rectangle of the jigsaw 1200 x 800mm and asked that the Jurek Putter mark at the edge of the artwork was included. The jigsaw cut cleanly and beautifully. The picture at the top is of the jigsaw on the laser after cutting. It filled the whole machine bed. Laser cut mdf edges are black and they contrasted well with the picture side and the white back of the puzzle.
Wendy was delighted with the results, and so was the Scottish Fisheries Museum.