it's getting better

On Tuesday Torsten found some time to experiment with our printer. 

The results are looking good, we got less warping than the last time we tried. 

One factor to reach this was to turn of the fan that cools down the print. Due to this the layers ould cool down more slowly. It's not perfect yet, we need to do some further settings but we got ideas for this. 

As one point we can extend the time the printer must use per layer to print to give the material more time to settle down. And the temperature of the heated bed is not really precise.

To keep the temperatur on the printing surface more constant, we will isolate it. Therefor we will use corrugated cardboard, as mentioned in by Nophead. The cardboard will be coated with a layer of adhesive aluminum tape and will be clamped under the heated bed. 

To shorten the time we need to reach the set temperature we will also lay a piece of corrugated cardboard as insulation on the top of the printing surface. We just need to remove it before the print start :) 

As mentioned before we're not sure with the temperatures on the printed bed. We didn't measure it till now and depend on the temperature the thermistor is giving us. But the thermistor is down on the headed bed, not on the upper side of the glass. So we need an adequate thermometer to measure if we got the wanted 110°C on the surface.

Calibration angle - you can see the warping ends

The overhang on the left seems to be thru the waping too,other edges are straight

the Backside

The first 'real' part - ripped of the bed while printing

With the well done angle, Torsten tried to print the first 'real' part. He decided to try a pulley, one of the smallest parts from our printer. Due to the warping the egdes lifted off the surface, so the hotend ripped it of the printbed after a few layers.