3D printing Widgets

I tool have had brittle filament but not breaking during a print only some hours afterwards and it always breaks in two places simultaneously, 
First near the extruder and also near the spool. As it breaks with quite a "ping" I expect the shock of one going triggers the other.
As a result I have quite a collection of filament "pieces" each about a foot long.
 
Not found much use for them so far but I keep them just in case I do. 

That tilt / pivot is worth looking into for all sorts of projects.  Thanks a lot.

 

And another for the printing / CAD folk.  I noticed there was a video showing how to add surface detail to a CAD model to give the impression of rivets or hatches. Now the so-called rivets are sunk into the skin of someones engine cowl model rather than slightly proud as one would expect but the techniques for aligning such details with either a simple or a complex body. The video involves a number of steps but mostly takes it slow. If I was going to try this I would start with something simple to get the pattern of CAD interactions sorted.

Here is the link:

 

Folk, I just came across a site that explores options for using 'modifier' objects (like blocks
and columns) to alter both the form and internal attributes of 3D printed objects.  

Simple example is a downloaded prop.  It has an overly small shaft so in the slicer
add a modifier, in this case a cylinder body of the correct radius at the shaft position
and 'subtract' it.  That sort of thin is widely used.

The site also showed more than a dozen other things you can do with that kind
of body - like have a different kind of infil or a different density, or a different number
of perimeters or base layers or printing temperature.  

Mind boggling with some slicers you can take an imported STL and make it a modifier.

Ideas bubbling up - take a fuselage that has a gyroid infil and increase the
density near critical stress points or up the perimeters in a few critical places.
Or near where mounting bolts will pass.  If and when I get my man cave in
Wales I am certain to explore this....

For those who can cope with YouTube here is the link:


 

jon
Yes it is a very useful facility to locally alter the print attributes in a bigger component.
My only grumble is if you later modify the original CAD file you have to remember that a) it used a modifier, b) what additional characteristic were specified for it and c) what was the modifiers file name if indeed you did save it. 

On one of my "test" props I did do this so the hub & blade root were "solid" with a specified bead direction but the rest of the blade had two stages of reducing infill %. It certainly made a lighter prop with very little reduction in stiffness but I was concerned at having "step" changes in its internal construction giving potential stress points.
For a less highly stressed component the use of a modifier is very neat process.

Tony, you mentioned putting together a test rig for props.  I looked back over my old photos and found this of my printed rig.  It works with a kitchen scale to find thrust.  The surround was limited by the small size of my print bed but certainly could be scaled up. Surround did once catch a blade fault so well worth including.  I might be able to find the freeCAD files and could have a go at scaling it up if needed.