ReChain self centering: Difference between revisions
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The not yet tensioned pre-assembly may be skewed in some slightly random way though. <br> | The not yet tensioned pre-assembly may be skewed in some slightly random way though. <br> | ||
This skew might or might not be ok. Just one thing to look out for. <br> | This skew might or might not be ok. Just one thing to look out for. <br> | ||
=== Geometry caused stress concentration (limiting compressive strength) === | |||
At the smallest scales with [[multi V-groove self-centering]] <br> | |||
the tip and base cutoffs to make just slanted sides contact <br> | |||
can become big relative to the remaining contact area <br> | |||
leading to undesired stress concentrations and thus to reduced maximal compressive stress. <br> | |||
This can also be an issue for self centering macroscale parts near the lower end of the manufacturing capabilities. <br> | |||
This an also bean issue of design not aiming for maximal preservation of material strength. <br> | |||
{{Wikitodo|Eventually add a sketch.}} <br> | |||
== Related == | == Related == | ||
Latest revision as of 12:30, 5 September 2026
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This page is part of the ReChain project. Short for Rebar CoreChain Systems. For an index of all pages of this project, see the category page ReChain. |
(wiki-TODO: Add the already made illustrative image. This shows details on do's and don'ts.)
One good design scheme:
- Trapezoids ridges going into V-shaped grooves.
- Only the flanks touch the flanks. The main coplanar surfaces do not touch.
- To avoid some slide-rotations always use at last two mating structures. (These may be parallel or normal to each other.)
- Eventually constrain all degrees of freedom of the pressed together surface contact. (This can involve more than two parts.)
3D printing context
FDM/FFF termoplastic printing
Not all flanks properly contacting due to printing inaccuracies
may perhaps be compensatable by some material flex when using polyamide (PA/nylon).
polyamide (PA/nylon) is challenging to print though (shrinkage, bed ashesion, heated chamber)
Fiber fill makes it better printable but removes the flex, so that defeats the purpose.
Fibers may help reducing creep issues tough.
SLA resin printing
SLA printing may be better as it's higher resolution and more accurate across the layers,
though one might want to go for smaller parts then and
choices for permanent high compression force tolerant material are likely more limited (2025).
Nanoscale APM & crystolecule context
Atomistic corrugations will certainly interfere with the
groove bases self centering approach in some way or an other.
When pressed together by ReChain Tensioning
and applying e.g. the "two mating line structures" method (as described above)
then maximally mismatched hill-on-hill alignment may be enforced and thus be ok too.
The not yet tensioned pre-assembly may be skewed in some slightly random way though.
This skew might or might not be ok. Just one thing to look out for.
Geometry caused stress concentration (limiting compressive strength)
At the smallest scales with multi V-groove self-centering
the tip and base cutoffs to make just slanted sides contact
can become big relative to the remaining contact area
leading to undesired stress concentrations and thus to reduced maximal compressive stress.
This can also be an issue for self centering macroscale parts near the lower end of the manufacturing capabilities.
This an also bean issue of design not aiming for maximal preservation of material strength.
(wiki-TODO: Eventually add a sketch.)