more exercises

README.md

@@ -2,9 +2,10 @@
 
 DEX is a small materials testing machine that should be capable of running tensile and compressive tests at up to 600N of force.
 
-| | |
-| --- | --- |
-| ![dex](images/2019-10-17_dex-01.jpg) | ![dex](images/2019-10-17_dex-03.jpg) |
+![dex](images/dex-iv-rhinocad-image.jpg)
+![dex](images/2019-12-12_dex-iii-iv-01.jpg)
+![dex](images/2019-12-12_dex-iii-iv-02.jpg)
+![dex](images/2019-12-12_dex-iii-iv-03.jpg)
 
 ## Operating Principle
 
@@ -32,38 +33,31 @@ CAD for the machine is available in this Repo, [under `cad/fusion`](https://gitl
 
 Part numbers are from [McMaster Carr](http://mcmaster.com) unless otherwise linked.
 
+... choice of sheet material: mill w/ composite, or laser w/ acrylic or delrin,
+
 | Part | Spec | Count | Notes | PN / Link | Cost / Per |
 | --- | --- | ---: | --- | ---: | ---: |
-| Delrin (Acetal) Cast Sheet | 24x12", 0.25" Thick | 2 | Fits on 24x18" w/ no mistakes | 8573K35 | $50.49 / 1 |
+| Acrylic Sheet | 24x12", 0.25" Thick | 2 | - | 8505K755 | $19.93 / 1 |
 | PLA 'Tough' |  | ~ 300g | Many 3DP Mechanical Bits | [Matter Hackers M6E9T65K](https://www.matterhackers.com/store/l/light-blue-pro-series-tough-pla-filament-175mm-1kg/sk/M6E9T65K) | $52.00 / 1kg |
-| 625ZZ Bearings | 5x16x5  | 24 | - | [VXB 625ZZ](https://www.vxb.com/20-625ZZ-Shielded-5mm-Bore-Diameter-Miniature-p/625zz20.htm) | $24.95 / 20 |
-| Bearing Shims | 5x10x0.5 | 37 | - | 98055A098 | $8.62 / 50 |
-| Carriage Shoulders | M4x5x6 | 12 | - | 92981A146 | $2.16 / 1 |
-| Reduction Shoulder | M4x5x10 | 1 | - | 92981A030 | $2.32 / 1 |
-| Idler Shoulders | M4x5x20 | 5 | - | 92981A042 | $2.33 / 1 |
-| NEMA 23 Stepper Motor | > 56mm Can Length | 1 | Spec Shaft with Pinion | [Stepper Online](https://www.omc-stepperonline.com/nema-23-stepper-motor/nema-23-bipolare-1-8deg-1-26nm-178-4oz-in-2-8a-2-5v-57x57x56mm-4-fili.html) | $14.83 / 1 |
+| 625ZZ Bearings | 5x16x5  | 13 | - | [VXB 625ZZ](https://www.vxb.com/20-625ZZ-Shielded-5mm-Bore-Diameter-Miniature-p/625zz20.htm) | $24.95 / 20 |
+| Bearing Shims | 5x10x0.5 | 26 | - | 98055A098 | $8.62 / 50 |
+| Carriage Shoulders | M4x5x6 | 13 | - | 92981A146 | $2.16 / 1 |
+| NEMA 23 Stepper Motor | 56mm Can Length | 1 | Spec Shaft with Pinion | [Stepper Online](https://www.omc-stepperonline.com/nema-23-stepper-motor/nema-23-bipolare-1-8deg-1-26nm-178-4oz-in-2-8a-2-5v-57x57x56mm-4-fili.html) | $14.83 / 1 |
 | GT2 Pinion | 20T | 1 | Spec Shaft with NEMA 23 | [Amazon](https://www.amazon.com/Saiper-GT2-Teeth-6-35mm-Synchronous/dp/B07MGMBX3N/) (or) [RobotDigg](https://www.robotdigg.com/product/226/20-Tooth-2GT-Pulley-10pcs-per-lot) | $9.96 / 5 |
-| GT2 Closed Loop Belt | 280T, 6mm Wide | 1 | - | [Amazon](https://www.amazon.com/280-2GT-6-Timing-Belt-Closed-Loop/dp/B014SLWP68/) (or) [RobotDigg](https://www.robotdigg.com/product/283/260mm-264mm-268mm-280mm-284mm-288mm-or-294mm-gt2-endless-belt) | $15.88 / 10 |
-| GT3 Open Loop Belt | ~ 1m, 9mm Wide | 1 | - | [Amazon](https://www.amazon.com/Ochoos-Timing-Rubber-Backlash-5Meters/dp/B07MWD9D7V/) (or) [RobotDigg](https://www.robotdigg.com/product/597/3GT-9mm-or-6mm-wide-open-ended-belt) | $15.00 / 1 |
-| 6806 Bearing | 30x42x7mm | 2 | x | 6806-2RS [VXB](https://www.vxb.com/6806-2RS-Bearing-30x42x7-Sealed-p/6806rs.htm) | $12.95 / 1 |
-| M3 Inserts | Tapered, 3.8mm Tall | ~ 300 | - | 94180A331 | $12.92 / 100 |
+| GT2 Closed Loop Belt | 200T (400mm long), 6mm Wide | 1 | - | [Amazon](https://www.amazon.com/400-2GT-6-Timing-Belt-Closed-Loop/dp/B014U7OSVA/) (or) [RobotDigg](https://www.robotdigg.com/product/286) | $15.88 / 10 |
+| 1204 x 400mm SFU Ball Screw Kit | | 1 | | [Amazon](https://www.amazon.com/SFU1204-Ballscrew-RM1204-Housing-Machine/dp/B076PCVC8F/)
+| M3 Inserts | Tapered, 3.8mm Tall | 200 | - | 94180A331 | $12.92 / 100 |
 | M4 Inserts | Tapered, 4.7mm Tall | 16 | - | 94180A351 | $14.96 / 100 |
-| M5 Inserts | Tapered, 6.7mm Tall | 4 | - | 94180A361 | $12.00 / 50 |
-| M3 Washers | 18-8 Standard Flat | 300 | - | 93475A210 | $1.62 / 100 |
 | SHCS | M3x16 | 100 | Pinning T- to the wall, and pulley endmatter | 91292A115 | $5.87 / 100 |
-| SHCS | M3x20 | 100 | Pinning T- to one another (?) | 91292A123 | $6.78 / 100 |
-| SHCS | M3x25 | 100 | Pinning T- and X-es together | 91292A020 | $7.23 / 100 |
-| SHCS | M3x45 | 8 | Pinning the 'squat' together | 91292A025 | $12.21 / 50 |
-| FHCS | M3x10 | 30 | Pinning blisters to faces | 92125A130 | $5.81 / 100 |
-| FHCS | M3x25 | (?) | - | 92125A138 | $11.50 / 100 |
-| Steel Dowel Pins | 5x8mm | 10 | - | 91585A506 | $8.40 / 25 |
+| M3 Washers | 18-8 Standard Flat | 300 | - | 93475A210 | $1.62 / 100 |
+| SHCS | M4x16 | 6 | Mounting Ball Nut | 91292A118 | $8.13 / 100 |
+| SHCS | M5x20 | 4 | Motor Mounting | 91292A121 | $9.03 / 100 |
+| Locknut | M5 | 4 | Motor Mounting | 93625A200 | $6.46 / 100 |
+| SHCS | M8x30 | 2 | Loadcell Fixturing | 91292A149 | $10.13 / 25 |
 | Feet | M4 Stud, 15x15mm | - | - | 93115K881 | $1.78 / 1 |
-| **Approximate Mechanical Total** | | | | | **$446.80** |
 | Loadcell(s) | 10, 30, or 50kg | 1 | Choose Range for Sensitivity | [Amazon 50kg](https://www.amazon.com/Pressure-Force-S-type-Sensor-Cable/dp/B01F6IOW3G/) [Amazon 30kg](https://www.amazon.com/Pressure-Force-S-type-Sensor-Cable/dp/B01F6IOWDG/) [Amazon 10kg](https://www.amazon.com/Pressure-Force-S-type-Sensor-Cable/dp/B01F6IOW4K/) | $39.00 / 1|
 | Loadcell Amplifier | HX711 | 1 | - | [Sparkfun 13879](https://www.sparkfun.com/products/13879) | $9.95 / 1 |
 | Power Supply | 350W 24V LRS-350-24 | 1 | - | [Amazon](https://www.amazon.com/MEAN-WELL-LRS-350-24-350-4W-Switchable/dp/B013ETVO12/) | $32.25 / 1 |
-| **Rough Control Total: Incomplete** | | | | | **81.20** |
-| **All Up** | | | | | **$528.00** |
 
 ## Control and Interface
 
@@ -94,7 +88,7 @@ Here we can see a desktop test - I am reading the X- position from my tracking s
 
 #### Vision on the Machine
 
-To get after this, next step here is to integrate a camera onto the DEX mechanically. The previous work taught me that (1) strong lighting is important, as is clarity of target-against-background. Some prep will be worth it. This is a fitting (haha) time to re-design the fixturing for the DEX, as the targets / camera / fixturing system will all need to agree with one another. 
+To get after this, next step here is to integrate a camera onto the DEX mechanically. The previous work taught me that (1) strong lighting is important, as is clarity of target-against-background. Some prep will be worth it. This is a fitting (haha) time to re-design the fixturing for the DEX, as the targets / camera / fixturing system will all need to agree with one another.
 
 ## Testing Notes