I want to get a measurement of the current being outputted to my feed stepper motor in real time. I believe I could use this information with the stepper's spec to estimate the torque output of the stepper at any given time (and thus determine the pressure drop across the hot end). What's the best way to achieve this? From what I've heard there's no convenient software in place that'd make tby rm446 - RAMPS Electronics
Is there a way to get my ramps board to display the voltage/current signals it's sending to one of my stepper motors in real time? Specifically I want to see the signal of my filament feed stepper motor as I tell my printer to do stuff via Pronterface (though if the solution involves another program that'd work too). I'm wondering if I could use this data to get the power/torque the motor is ouby rm446 - RAMPS Electronics
Interesting A2, I was not aware of the oxidize layer thing. I did notice this paper mentioned the layer to layer bond strength analysis assumed "perfect wetting" which I'm guessing means it ignores imperfect contact due to things like the oxidization layer you mention. I wonder with spherulites though, are those present in significant quantities on FDM filament? I remember that spherulites areby rm446 - General
It's out now! I got myself a copy and it does contain some complex/detailed formulas for things like pressure drop across the liquifier, temperature distributions, etc. A good chunk is how different processes affect mechanical strength. Over all I'd say its very useful if you're very interested in theoretical scientific approaches to what's going on and not afraid of dimensionless equations.by rm446 - General
Indeed DaveX, there is a lot that is uncontrolled with consumer/reprap 3D printing today, but that just means a theoretical model would be that much more useful. Even though material properties vary from spool to spool, I'm willing to bet the same spool will have consistent properties (well assuming you don't leave it in a humid bathroom for 3 months in the middle of its lifecycle). Outside ofby rm446 - General
I've commonly heard of acetone being called a "solvent" for ABS, but what does it actually do to the ABS on the polymer chain level? I assume it's not breaking down the polymer chains becuase ABS disolved in acetone seems to be recoverable once the acetone evaporates. On a similar note, does THF break down the polymer chains of PLA? I'm interested in this because I want to find a scientific exby rm446 - Polymer Working Group
Dang! I've been looking for something like this for the last couple of weeks. I'd love to have a more theoretical/quantitative model for whats going on in the FDM process. Unfortunatly it looks like this issue isn't out yet. It's marked as an "EarlyCite" article which means what we're seeing is just a preview. (For more info on that website's "EarlyCite" thing see this link: ). It looks liby rm446 - General
How do the developers of slicer software get there default settings? Are they just found via experimentation or are they based on some theoretical relationship between hot-end temperature, feed rate, and head speed? (or are they just tribal knowledge?) Basically I'm interested in learning the physics of what's going on with FDM printing in depth (I'm a mechanical engineer so feel free to be tecby rm446 - General