Summary

A Merman Model that is made from a bunch of derivatives

Instructions

You might need to scale this model to fit your printer, and reasonable scaling should produce good results.

You should probably print this with support material enabled, although if you modify the arm angle in blender you might be able to get it to print without support.

I removed my support up with a pair of wire cutters and did some smoothing with a nail file and a Rotary Tool. Be careful on the hands as the fingers are rather fragile.

I Printed with ABS White plastic

Be warned this model is not open scad friendly out of the box; blender is the recommended editing software for this model.

Yes, I am aware that one of the hands is at a questionable angle, this is easy to fix in blender; however, I like to call it an artistic signature.

Likewise, this model could use some more refinement and segment scaling and smoothing to look better. Nevertheless, this model was designed based upon the fact that printing acts like a mechanical filter that will remove most of the joint imperfections; However, feel free to clean it up in blender.

I like to run my printer slow and steady since my print deck has a tendency to dance around a bit so your configurations will vary.

I printed it with the following slicer settings

Layers and Perimeters
Layer height .3
Vertical shells 2
Solid layers 4 top and 2 bottom

Infill
Fill Density .25
Infill 1
Solid infill every 6
Fill angle 45
Solid infill threshold area 70

Speed
Perimeters 50
Small perimeters 50
Infill 50
Solid infill 50
Top solid infill 50
Support material 60
Bridges 50
Gap fill 40
Travel 60

Filament and Temperature
I was printing with 1.75mm filament with a bed temperature between 95C to 110C and a hot end temperature of 220.