add N23 CAD, 90block cad

README.md

 # Roller Coaster Gantries
 
+Parametric, low-complexity fabrication linear axis designs using ubiquitous hardware.
+
+## Gantry for NEMA23 Motor, 1/4" Aluminum
+
+![RCTN23-025ALU](images/RCTN23-025ALU.png)
+
+[RCTN23-025ALU Fusion CAD File](cad/RCTN23-025ALU_v49.f3d)
+
  - kinematic mounts are three button head cap screws on 20mm grid w/ reciprocal / wherever-u-like mount ins 
  - all axis have scroll-along top plate w/ connection to motor plate, final scroll kinematic triangle 
  - all axis have scroll-along bottom beam plate w/ 20mm grid w/ last scroll kinematic triangles 
 
-## BOM
+### BOM
 
 ### Hardware 
 
@@ -21,107 +29,8 @@ FHCS | Flat Head Cap Screw: similar to SHCS but have triangular heads, used when
 BHCS | Button Head Cap Screw: rounded head socket heads !
 PLSTCF | Plastic Thread-Forming Screws: have triangular lobed threads and torx drive caps, wonderful in plastics as the beefy threads mean no inserts required. 
 
+## 90 Degree Block for 1/4" Aluminum 
 
-``` OLD DOC: move this to /kunits/README.md and /kunits/images ```
-
-Scratch / Landing page for the roller-bearings and 2d-sheet-stock axis system.
-
-With RCT, we break axis into individual kinematic elements - and roll those elements into machine designs. 
-
-![gantries](/images/one-two-three.gif)
-
-A reasonable system for beginners, and easy to manufacture (with another CNC mill). Particularely, this system begets the [Madison Park Vocational Machine](https://gitlab.cba.mit.edu/jakeread/mpvm)
-
-![mill](/images/mpvm-v03.jpg)
-
-## Building Axis and Machines from 'Kinematic Elements'
-
-Machines are made of degrees of freedom, and those degrees can be assembled from 'Kinematic Elements' i.e. here I have one Motor / Pulley Unit, as well as Lateral (into the gantry) and Cross (across the gantry) supports. I'm doing a mediocre job of explaining this, but here are some images:
-
-To scratch a machine together, I pull elements into Rhino as .step files, and lay them out into axis - here's one linear degree of freedom:
-
-![basically](/images/kunits-basic.png)
-
-Then I assemble those axis together, keeping track of where I'll be adding plates of material:
-
-![units xz](/images/kunits-before-form.png)
-
-Then I go about filling in detail design, adding tabs etc to bring beams and chassis together.
-
-![one](/images/kunits-one.png)
-
-![two](/images/kunits-two.png)
-
-![three](/images/kunits-three.png)
-
-![four](/images/kunits-four.png)
-
-## Fabricating Axis 
-
-I then mill these axis on our shopbot, or any CNC mill you like - the N17 size elements can likely be laser-cut with acrylic or similar (delrin would be nice, but is expensive and a bit toxic to cut, so goes the lore). 
-
-![cam](images/mpvm-rhino-cam.png)
-
-I do CAM in Fusion with a .step I export (after flat-packing) from Rhino.
-
-![mill](/images/mill.jpg)
-
-## Assembling Axis
-
-I typically assemble machines one axis at a time. That's not saying much, but here's an image to get a sense of how the hardware goes together:
-
-![one](images/rct-one-rob.jpg)
-
-The 'adjustable' elements use a captured nut to pre-load bearings against gantries. TODO is better documentation of this, but here's an image of the flexure in simulation to get a sense for what I mean:
-
-![sim](images/preload-sim.png)
-
-# CAD for You
-
-### RCT Elements NEMA17 Size 
-
-CAD For these elements is available in the repo [cad/elements/rctElementsN17](cad/elements/rctElementsN17)
-
-This set assumes you're building with 1/4" HDPE or similar, Nema 17 Motors with GT2 Pulleys of 6mm width, and have access to a set of M3 Socket Head Hardware and 'MR115' or '5116' trade names or similar, 5x11x4mm. Lots of those.
-
-### RCT Elements for NEMA23 Size
-
-CAD For these elements is available in the repo [cad/elements/rctElementsN23](cad/elements/rctElementsN23)
-
-This set assumes you're building with 3/8" HDPE or similar, Nema 23 Motors with GT2 Pulleys of 9mm width, and have access to a set of M5 Socket Head Hardware and 'skate bearings' - 608ZZ or similar, 8x22x7mm. Lots of those.
-
-## Hardware Notes
-
-! to add here
- - hardware stackups, BOM, tuning note 
-
-## Notes for Jake
-
- - RCT Mod
-  - tabs on rail supports still no bueno 
-  - std. order side-wall taps / wall-to-surface -
-  - of course the belt tensioning needs help ... fold-over or something ? glue it down? single track? 
-  - belt tender assy - 3dp walls, bearings to hold-down, m4 screws on to carriage at edges ?  
-  - motor rotational tensioning: pin one 
-
-  - and make tools for drill, tap 3dp 
-   - also drill / tap m6 / m4 verticals 
-   - m4.3 or similar nice for m4 thru on motor 
-
-
-  - order up tiny clampz 
-
-## BOM
-
- - [N17 Bearings](https://www.amazon.com/5x11x4mm-Replacement-Precision-Bearings-MR115-2RSBU/dp/B00Y5W3JYS/)
- - [N17 Pulleys and Belts](https://www.amazon.com/DerBlue-Meters-Aluminum-printer-Rostock/dp/B0714R39BC/)
- - [N23 Bearings](https://www.amazon.com/608-2RS-Skateboard-Bearing-Rolling-bearings/dp/B073ST742Z/)
- - [N23 Pulleys and Belts](https://www.amazon.com/2GT-Timing-Belt-10Meters-Pulley/dp/B01COEMZC0/)
-
-# Machines using RCT Gantries
-
-![mill](/images/mpvm-v03.jpg)
-[Madison Park Vocational Machine](https://gitlab.cba.mit.edu/jakeread/mpvmachine)
+![RCTBLK-90-025ALU](images/RCTBLK-90-025ALU.png)
 
-![smallgantry](images/smallgantries-fab.jpg)
-[Small Gantries Workshop Machine](https://gitlab.cba.mit.edu/jakeread/smallgantries)
\ No newline at end of file
+[RCTBLK-90-025ALU Fusion CAD File](cad/RCTBLK-90-025ALU_v6.f3d)

kunits/README.md

-``` OLD DOC: move this to /kunits/README.md and /kunits/images ```
+``` OLD DOC: depricated hardware ```
 
 Scratch / Landing page for the roller-bearings and 2d-sheet-stock axis system.