Owrigami
Pentagon Module
I am re-posting this module which was created [discovered] in 1990. The main reason for re-posting this is that I found a more logical way to get that odd angle. The method is quite accurate but I do not think that it is Mathematically correct. The method is best illustrated by the photo diagram. Briefly, it shows the angles [in black] required for 4, 6, 8 modules assembly like stars, and coasters. Those angles radiate from the bottom left corner to the middle crease line. These angles can be easily generated by simple folds. Therefore, in order to get the angle required for a 5 piece assembly, logically, that angle should be in between 4 and 6. Can I logically assume that the bisector [circled and in red] the correct angle? Likewise, for a 7-piece assembly I take the bisector of 6 and 8 to be the correct angle. The interesting part here is that, that angle radiates from the corners to almost the middle of the opposite edge. I have assembled some 7 piece coasters quite accurately with this and will post them in due course. More details of this module was posted in 1993 - www.flickr.com/photos/61236172@N08/11003407114/in/datepos...
Pentagon Module
I am re-posting this module which was created [discovered] in 1990. The main reason for re-posting this is that I found a more logical way to get that odd angle. The method is quite accurate but I do not think that it is Mathematically correct. The method is best illustrated by the photo diagram. Briefly, it shows the angles [in black] required for 4, 6, 8 modules assembly like stars, and coasters. Those angles radiate from the bottom left corner to the middle crease line. These angles can be easily generated by simple folds. Therefore, in order to get the angle required for a 5 piece assembly, logically, that angle should be in between 4 and 6. Can I logically assume that the bisector [circled and in red] the correct angle? Likewise, for a 7-piece assembly I take the bisector of 6 and 8 to be the correct angle. The interesting part here is that, that angle radiates from the corners to almost the middle of the opposite edge. I have assembled some 7 piece coasters quite accurately with this and will post them in due course. More details of this module was posted in 1993 - www.flickr.com/photos/61236172@N08/11003407114/in/datepos...