Feedback and Questions
- Eva Ulbrich
Are there printers which can print with several colors?
Yes, there are. However, unfortunately it is rather complex because for eg. FDM, every material needs to be heated up to the melting point. In case you used the same nozzle, for different colors you would have to extrude some material all the time to have pure colors since some of the material always remains in the nozzle. In case you had more than one nozzle, you could use one color per nozzle. Unfortunately, these printers are a lot more expensive. So in case you want to have parts in different colors it is best to print first one color, then exchange the filament material, and then print all parts in the next color and so on until you have all parts with different colors. Afterwards, you can assemble them and/or glue them together if you want.
What is the material we use called, what features does it have?
The material often used with FDM is PLA - Poly Lactic Acid - which is often made by using corn. https://en.wikipedia.org/wiki/Polylactic_acid it is biodegradable in industrial recycling processes. It can be reused but other materials are better suited for that. It does not emit poisonous gases when heated and it is not bending around much when being print like other materials - this makes it easy to use. Please do not use it for very hot things though: the glass point - when it starts to get soft - is at 60 degrees. Do not make a cup with it for hot coffee! The hot coffee will melt your cup and even if it is not poisonous, you still might want to avoid drinking melting plastik!
I dont remember all of this, can we have a video?
We are working on that :) We will provide it as soon as we can.
How hot should I heat up my nozzle to insert the filament?
Wait until the nozzle heated up to the temperature where you would melt the filament material. Only afterwards, take out or put in filament - otherwise, it will be stuck. You should find the needed temperature at your material - for PLA it is often around 200 or 210 degrees. Every color needs to be handled differently though, only slightly but still different. For example, one color could need 205 degrees while another color could need 215 degrees for proper melting. The reason is, that the colors added to the material also change the attributes of the material just a little.
Can we at the beginning of the course download something from Thingiverse and print it out meanwhile?
3D printing takes a looooot of time. So yes, we can do this for really small things. A small toy house takes already half an hour to print and not every print always works. We could sit for a really long time so we suggest to print something small and easy to print like a cookie cutter.
You always talk about rotation. Why should we rotate?
Several reasons make it useful to rotate alot. We work with two dimensional screens so we do not really see three dimensional on our screens. However, the items we work with are three dimensional. So perspective can sometimes deceive you and show things a bit different that they really are. You do have little visual information how close or far away or how big things really are. So rotate your workplane, rotate items also sometimes to get better printing results or reduce support material or printing time.
How long should the printer run, is it a problem if it runs through the entire day every day?
The longer the print, the more errors can occur. You should at least stay at the printer for the first few layers but it is recommended to stay near the printer all the time because in case the print goes sideways, you should be able to stop and restart to not loose time and material. If you run the printer very intensely, you might need to change the nozzle every half a year.
Can we reuse material?
In general, 3D printing is eco friendly and material can be reused to an extend. PLA, the material you are using, is however, not the best material to reuse. ABS or PETG - two other materials - can be reused more easily. They can be granulated and reused up to nearly 100 percent. The biggest challenge in reusing material is that it needs to be collected color by color. Every color and material brand causes slight changes the materials attributes and they should not be mixed if possible.