diff --git a/UrumbotXYZ/fixed_axis/README.md b/UrumbotXYZ/fixed_axis/README.md index ed2d767870a2a71e8c9d4bbc3d21c5a45ea1b96b..fe913d82e211809def501520ce351f1725bea956 100644 --- a/UrumbotXYZ/fixed_axis/README.md +++ b/UrumbotXYZ/fixed_axis/README.md @@ -115,10 +115,14 @@ Kevlar string wrapped around stepper axle, tension in string opposed by spindle #### Progress as of 4/27/22 - Kevlar string measured. Creep and hysteresis were below measurement sesitivity on my apparatus. Elastic constant K = 9.5kN. That is, for one meter, dF/dx = 9.5 N/mm. <a href="https://gitlab.cba.mit.edu/classes/865.21/projects/machinemetrology">Details.</a> - - With this string, wrapped directly around motor shaft, and using weight of the spindle as the sole downward force, it is possible to mill a reasonable PCB with the conical bit, and wax milling goes well. Measured dF/dz is much higher than before, 120 N/mm. + - With this string, wrapped directly around motor shaft, and using weight of the spindle as the sole downward force, it is possible to mill a reasonable PCB with the conical bit, and wax milling goes well. Measured dF/dz is much higher than before, 120 N/mm. - The xy stage by itself has dF/dy ~ 40 N/mm. With wax block on table, at the top of the block dF/dy = 30 N/mm. Extra compliance is due to rotation about the single x-beam as a function of sideways flex of bearings. - Applied kevlar string to the xy stage. Now the stiffness of the stage, dF/dy, has doubled to 80 N/mm. When the table is added, and a wax block attached, the stiffness at the top of the block is still low, about 40 N/mm. Now the 20mm width of the x-beam is the limiting design parameter. +[Youtube video of was milling](https://youtube.com/shorts/Uz45yHX_n6A?feature=share) +<img src=./img/milled_wax.jpg width=40%> +<img src=./img/adjuster.jpg width=40%> + #### Next steps. - Make a double-beam for the x-axis. This will triple the torque arm for the stage. diff --git a/UrumbotXYZ/fixed_axis/img/adjuster.jpg b/UrumbotXYZ/fixed_axis/img/adjuster.jpg new file mode 100644 index 0000000000000000000000000000000000000000..a2e3d1e1198cfb687d78d60c52b882f0af7be1c6 Binary files /dev/null and b/UrumbotXYZ/fixed_axis/img/adjuster.jpg differ diff --git a/UrumbotXYZ/fixed_axis/img/milled_wax.jpg b/UrumbotXYZ/fixed_axis/img/milled_wax.jpg new file mode 100644 index 0000000000000000000000000000000000000000..7161d5bd7e9b7133e18aab4e33d86c01b5985ea3 Binary files /dev/null and b/UrumbotXYZ/fixed_axis/img/milled_wax.jpg differ