How to determine the right temprature for a material

[uma 0]

Folks,

I would like to know about what kind of tests people do to find the right temperature for different material. I am finding that different material (PLA) work well at different temperature. In fact, i found that temperature impacts the bridging quality as well. (I kept the same temperature when i went from blue to green only to find that my part was unusable, i attribute this to temperature because the same part printed well with blue).

So, I want to know what kind of tests people do to identify the optimal temperature for a particular material. Any best practices that you follow, please share in this thread.

 

[gr5 2,230]

This is a good question for google groups. You should post it there also.

https://groups.google.com/forum/?hl=en#!forum/ultimaker

 

[3dmaker4u 0]

My procedure is as follows:

 

1. Start with 220 Celsius.
   
2. Set extrusion speed at 40 mm/s (that's what I'm using for most prints).
   
3. Extrude 20 mm.
   
4. Check quality of the extruded wire: it should be smooth, glossy and strong.
   
5. If not, increase temperature in 5 Celsius steps, repeat 3 and 4 above and check here.
   
6. If extrusion tend to be rougher, it means temperature is too high, go back to 215 Celsius, repeat step 3 and 4, downwards in 5 Celsius steps and check here.
   
7. After a few iterations, I get a range of good extrusion temperature, where the lower limit is signaled by rough extrusion (usually well before the extruder starts skipping steps).
   
8. Thea actual temperature depends mainly on the printing speed, but if the filament does not ooze excessively, I can easily print with one temperature from 20 to 80 mm/s.
   

Well, please note that I'm not using an UM, but I thing the procedure is machine independent.

 

[uma 0]

@3dmaker4u, thanks for your suggestions. I shall try it out and post back

 

[3dmaker4u 0]

Oops! I just saw an error. The speed in my previous post is NOT extrusion speed, but rather the... printing speed! Or the retraction speed for some

Then, you have to calculate the actual extrusion speed that is obtained as follows:

Notations:

Df = diameter of the filament

Dn = diameter of the nozzle

Ps = printing speed

Es = extrusion speed

Then:

Es = Ps * ( Dn / Df ) ^ 2

For example: Df = 3 mm, Dn = 0.4 mm, Ps = 40 mm/s results in Es = 40 * 0.01778 = 0.711 mm/s or 42.67 mm/min.

I apologize for any inconvenience.