CuraPlugin: Flowthermostat
Contents |
Flow Thermostat Plugin for Cura
This plugin adjusts the heater temperature to match the reduced flow when using the built in Cool feature. This allows for faster and more high quality prints.
Features
- Stops overheating of the top of tapering objects
- Stops filament overheating in heat block during slow printing
- Automatically adjusts the print temperature so that it is proportional to the flow of plastic through the nozzle
- Allows you to use your high speed settings for all objects, big and small (!)
- Takes the guessing out of choosing your maximum print speed
- Lets the user choose a different temperature for the first slow layers - Will be split off into a separate plugin
Instructions
This plugin takes your good profile settings and uses them to find as good settings for the slower speeds set by the Cool feature. This means that the instructions begin with finding one good print profile.
- Find a good high print speed and temperature combination (Cura profile) without using the Cool-feature. (When you have the Cool-setting on you no longer know what the real feed speeds are.)
- Now find a good layer cool time that works with your good profile.
- Set your profile in Cura, if you have many, preferably choose a good high speed profile for large objects, the plugin will make it work with smaller objects as well.
- Set your preferred starting layers temperature.
- Copy and Paste some values from your Cura profile into the plugin window. (Sorry about this.)
- Enter a lowest possible printing temperature for the current type of filament. Usually the temperature when the threads lose adhesion and the print becomes porous no matter how slow the feed speed is.
- Prepare print and Print as usual.
* The Thermostat slope constant is calibrated for a standard Ultimaker hot end, if you use something else you might need to change it.
Under the hood
Quick summary: The constant thermostatSlope is the linear relation between increasing flow and increasing print temp to achive the same print result at different print speeds. Calculated as thermostatSlope = (Delta temp ) / ( Delta flow ) This is done beforehand and the relation is assumed to be similar with all PLA colours.
Feed is linearly proportional to flow since nozzle and layer height is constant during the print.
In short plain text, if you know one good temp and speed combo you can calculate them all, for all layer thicknesses and speeds.
For the restless, some inspirational forum reading
Graph found in the thread above
Feel free to peek into the code as well, I am not a programmer by trade and this is my first attempt at Python, so you have been warned.
Download and installation
Follow link to select version and download: http://wiki.ultimaker.com/File:FlowThermostat.py
Installation instructions is found on the download page.
Future versions
Ideas for improvements
- Later versions will extract known profile data from the Gcode instead of having the user paste it in.
- Automatic conversion system for keeping your good print properties while changing layer thickness and/or nozzles diameter
- A list of calibrated Thermostat slopes for different hot ends. (I need to see your Flow/Temp graphs for this!)
- Data output to the Gcode as comments. Temp/flow, Feed speed/height and such. Possibly as a separate plugin.
- Create a converter for layer thickness temp translation
Implemented ideas
- Add a minimum print temperature option to the interface V1.1
Feedback
All user feedback is much appreciated. Post bugs, ideas for improvements or tell about you your experiences and that will help with improving it.
I am very keen to see your graphs of your flow rates and temperatures. More data will make this plugin much better.
