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Development Docs (#58)

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Improved development docs and link to it from README.
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Adrian Schlatter
2021-10-09 15:26:08 +02:00
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parent 91eb1b0121
commit 4bb8c70987
5 changed files with 44 additions and 28 deletions
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docs/BSPPthread.md
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@@ -2,7 +2,7 @@
The general approach is described in [Creating Thread Specs](./CreatingThreadSpecs.md). We explain the math here. The following figure is of great help to understand what is going on. Black profile: theoretical parting line. The profiles we are going to create are red (internal thread) and blue (external thread). Note that the red and blue profiles are drawn assuming identical pitch diameters for both to clarify the figure. However, in reality external and internal threads do not have the same pitch diameter (see below).
![Parting line of BSP-parallel thread with simplified external and internal thread profiles overlayed](imgs/BSPthread.jpg)
![Parting line of BSP-parallel thread with simplified external and internal thread profiles overlaid](imgs/BSPthread.jpg)
The relevant translation in done in the function calculateThreadlibSpecs() in BSPP_thread.awk.
@@ -11,7 +11,7 @@ Steps:
- Pitch (P): Taken from table BSPP_thread.csv
- Pitch diameter: external threads aim for a somewhat smaller pitch diameter (DPitchExt), internal threads for a larger one (DPitchInt). threadlib aims at the center of the acceptable range given in BSPP_thread.csv. For external thread, we have to choose between class A and class B. We decided for class A.
- Major diameter (for external thread, think minor diameter for internal thread) is chosen in the center of the acceptable range given in BSPP_thread.csv => DMaxExt, DMinInt
- Support diameter (DSupportExt, DSupportInt): Must be on the right side of the parting line. Otherwise no requirements from the norm. We choose the pitch diameter +/- 2 * 5/12 * H, where H is the full heigt of the fundamental triangle and +/- depends on external / internal thread. This is the middle between intended major / minor diameter and the corner of the fundamental triangle.
- Support diameter (DSupportExt, DSupportInt): Must be on the right side of the parting line. Otherwise no requirements from the norm. We choose the pitch diameter +/- 2 * 5/12 * H, where H is the full height of the fundamental triangle and +/- depends on external / internal thread. This is the middle between intended major / minor diameter and the corner of the fundamental triangle.
- The valleys of the actual part will be defined by the support (see above). The valleys of the profile are chosen to overlap somewhat with the support => DValleyExt, DValleyInt (these correspond to Rrot).