I started work on a 3x3x4 shortly after the first 4x4x4 came out in 1982. Since I now had a 3x3x3 Rubik's Cube and a 4x4x4 Master Cube / Rubik's Revenge I also wanted a 3x3x4 and 3x4x4. It seemed obvious to me that both could be made from a 4x4x4 but I wanted to make one from scratch. I set about designing a mechanism which closely resembled that of a 4x4x4 Master Cube. Naturally though it also had some similarities to a Rubik's Cube. Over a number of years from time to time I attempted to construct my design. However without rapid prototyping or any sort of decent tools all I could do was try and sculpture the pieces from polyester resin. Making a mechanism this way is virtually impossible and eventually I gave up.
I still wanted to possess a 3x3x4 though and decided to cheat (as I saw it in those days) and simply used a 4x4x4 to make one in 1995. I didn't even think of cutting it down first. I just made the extra pieces from polyester resin and glued them on. Little did I know that this technique would be talked about many years on and considered as a recognised method to make fully functional cuboids. The puzzle itself is enormous and very heavy. I did include some spaces to the add-on parts and drilled some holes after casting but the thing still weighs a lot.
This was almost certainly the first fully functional cuboid transformation in the world. Like several of my early puzzles the quality is very poor and making it was about my desire to own and solve it. Not to make it look nice. I had no intention of showing it to anyone, it was simply for me to play with.
Rotational quality is ok but not brilliant. The extra weight put great strain on the fragile 4x4x4 parts and often they would break. Sometimes simply through assembly.
Years later Eastsheen released a smaller more suitable 4x4x4 and I was able to make a version much better in every way. That was my 3x3x4 (medium) that I made in 2006.
The puzzle does not change shape since it does not obey the rule- "A cuboid is capable of shape changing when ( two or more edge unit lengths are different and odd ) or ( two or more edge unit lengths are different and even ) excluding cuboids with a side of one".
In total I have made twelve fully functional cuboids. They are-
2x2x3 (micro), 2x2x4, 2x2x6, 2x2x7, 2x3x4, 3x3x4 (large), 3x3x4 (medium), 3x3x5, 3x4x4, 4x4x5, 4x4x6, 5x5x6.