1 Topic by JustSomeGuyTN

  • JustSomeGuyTN
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  • Registered: 2012-08-31
  • Posts: 158

Topic: Does anyone adjust their bed temps for different colors of ABS?

I had a problem with flat sides pinching in after about the first 5 mm (z) of a print.  I was printing natural ABS from Solidoodle at a bed temp of 100c.  I did a couple of test objects, each at a lower bed temp.  I finally printed one at 85C that has only very slight pinching, hardly noticable.  But with black ABS from Solidoodle I was running at 100c and the plastic was still curling back into itself like it was a rubber band.  Now the black could have been exasturbated by the nail polish remover I was using to clean the bed.  I am now using isoporal alcohol.  So I'm wondering if it would be a good idea to test and run each fillament at a different temp?

2 Reply by IanJohnson

  • IanJohnson
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  • Registered: 2012-08-07
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Re: Does anyone adjust their bed temps for different colors of ABS?

The bending in is due to the heat from the bed keeping the lower layers from shrinking as much as the upper layers, which aren't getting heat from the bed.  The lower bed temperatures work better because there isn't as much difference between them. 

Different colors might shrink at different rates .  What you could do is print something like a cylinder or box that is tall enough for the upper layers not to get any heat from the bed.  Run the same gcode for several colors and see if the dimensions at the top layers come out any different.

The best fix for the pinching is to keep the ambient temperature inside the printer as high as you can to keep the temperature more even throughout the print.