- When Fluids Collide -
- Direct observation of the transfer of orbital angular momentum to metal particles from a focused circularly polarized Gaussian beam -
- parametric OpenSCAD model for a twisted box consisting of two parts that screw into each other. -
- Machine models and tool motions for simulating 5-axis machining -
CUI Encoders
Digikey corrected their mistake and shipped The Real McCoy to me today.
240 and 400 grit sanding
When not shopping online for lathe-electronics/parts I have been busy sanding the Pikanto moulds. First the last bits of 180-grit today, then all over with 240 grit, and finally started with 400 grit which I will have to continue with next in the next session. The flat bits and large gently curved areas of the hull are easy and quick to work with but as always the devil is in the details. The deck mould has a lot of edges and features that are tricky to sand, and all moulds have a sharp 90-degree edge which is easily damaged when handling the moulds.
The plan is to go 600-800-1200 grit next weekend and do a bit of polishing after that.
Mesa electronics 5I20 fpga-card
This PCI-card with an FPGA and 72 I/O lines will be used to control the lathe.
$199 from Mesa electronics
Links - 2009 Dec 3
- Development of a Multi-step Measuring Method for Motion Accuracy of NC machine tools Based on Cross Grid Encoder -
- Beginners Guide to HD Video in digital cameras -
- Canon EF 85/1.8 USM Review -
- Spinal Tap Amps -
- High-speed contouring control with NURBS-based C2 PH spline curves -
- Something to Chu On -
- Follow the Bouncing Water Droplet -
- Light Resonators Used To Move Nano-sized Objects -
- Mini Microbe Portraits From the Micropolitan Museum -
- Hull-form optimization in calm and rough water -
MPG
manual pulse generator.
Digikey FAIL
Spindle servo encoder shaft
The 1.75kW spindle-servo for the lathe only has resolver and hall-feedback. So I need to mount an incremental encoder with index pulse on it myself. The rotor for the hall-sensors attaches to the main motor shaft with an M6 bolt. Here I'm making my own M6 bolt with a long 'head'/shaft that will extend outside the back lid of the motor. I cheated a bit by starting with a 0.5" rod which already had an internal M6 thread. An M6 set-screw will form the bolt-part of the shaft, and is also used here to hold the part in the lathe. This was then turned down to ca 11mm to fit the hall-rotor, and 8mm for the part of the shaft that extends outside the motor and to which the encoder will mount.
Encoders are on order from digikey so they should arrive next week.
By taking it slow and measuring a lot the 1949 Schaublin makes parts with tolerances approaching 0.01mm!
Pikanto moulds
Our three-piece hull/deck-moulds for the Pikanto IOM (designed by Graham Bantock) are now ready. The next step is to sand the surface smooth and polish the moulds. We hope to mould a prototype hull before the new year.
Cake
