"Do you reckon you could make a sliding puzzle for us?" was how the opening line came across from local design service agency. Always ready to take on a challenge we set to and looked at what we would need to contend with in order to make such an unusual piece.
The client's wish was for a pair of sliding puzzles that were 1500mm square in size and fully functional in every respect. Given that this was yet again another Evans' first, we had to devise a production method that would allow us to accurately print, machine and then assemble all of the parts to create the oversized puzzles.
Not wanting to re-invent the wheel, we obtained a miniature sliding puzzle to check how it had been constructed. Once we had seen how the components worked together we started designing our own version, ensuring that we were able to work to the sizes and tolerances required to make this larger than life sized project.
The team initially created a scale size model to prove that their design could work and once that was agreed as workable, they then scaled the design from 80mm square up to 1500mm square!
Using heavy gauge plastics and solid sheets of foamed PVC the puzzle pieces gradually came to life. Possible the most demanding part was the printing of the tiles, which needed to be engineered to allow for the cutting tool clearance, but still appear to have been cut from one sheet when assembled. With the incredible accurate cutting table that Evans uses, keeping the accuracy spot on was not a problem. In fact, once the master grid was constructed, with the optical registration system capturing all of the targets, there was never any doubt as to the fit and function of the many parts.
With all of the elements prepared, the assembly commenced and consisted of using pin jigs, which were cleverly built into the internal framework of the puzzle. This ingenious system allowed us to very quickly and accurately fit all of the pieces together with a solid assurance that the alignment would be 100% spot on. To ensure that the pieces all moved smoothly and without hesitation, we applied titles, which ensured that when the tiles were moved they slid effortlessly within the boundary frame.
The end result was a perfect pair of gigantic sliding puzzles, each with 15 oversize tiles that could be moved around to build the correct picture. Our client was delighted, and the client's client was equally thrilled with the training aids that they had been able to obtain. | 
