Block folding or origami block (折り紙ブロック) as well as paper block (ペーパーブロック), origami handicraft (折り紙手芸), chinese modular origami and 3D origami are some of the designations of this particular type of origami. This particular type of origami is made with hundreds (literally) of the same small piece assembled in a shape of a particular model: animals, anime figures, fruits and just about everything one can think of.
This is the first “real” block folding posts following the mini pineapple one. The mini pineaple, final version, and swans are next! (:
This particular model was devised by me for one to understand how the pieces/ blocks “join” or are assembled together. I made it simple and with just 31 pieces/ blocks since if you want to understand it you don’t have to fold 300 or more pieces to just stare at them…
In some models there are some larger or smaller pieces to facilitate assembly but this post is just about the basics! You’ll need 31 rectangular pieces of paper. In the diagram I used 4 colours, as you can see in the photos, but you can do it in a single colour, two colours, or any number of colours! Publicity paper is fine too! The important thing is the paper resistance; the paper should be resistant but flexible enough or the model will be too sturdy to assemble and therefore will require glue.
The paper has a 1:2 proportion; for copy and printing paper 4×8 or 5x10cm paper, 1.50×3″ or 2×4″, is fine, the later being the better. If you have square coloured office notes, the ones without glue are better, you can just divide them in half, the size is just perfect! For magazine paper and similar papers you should use smaller papers: 2.5×5 or 3x6cm, 1×2″ or 1.20×2.40″. Anyway, if in doubt the bigger the paper, the better: it will be easier to fold and assemble. You can do another model with smaller pieces after you understand and assemble this first one (:
In the diagram file you’ll find the base diagram for the piece/ block and then the fish assembly. The assembly is first showed using standard representation of it (you can find similar representations in books about this type of paper folding) and then a summarised version of the assembly almost line by line. It starts at the fish head and then goes all the way up. Pay attention to where the pockets and flaps are according to the diagram; triangles with a line from base to the top are pieces/ blocks have half of them are left “free” to better represent fins.
If you like, you can use glue; if so, white glue for wood and DIY purposes, is good. Almost invisible when dry it doesn’t leave glue hairs/ strings and is easily reposition-able until dry.