Can fast printing affect filament color?

I tried to print a bit faster on few of my last prints. By faster I mean 3000mm/min, when usually I print 2000-2300 mm/min.

The result was that a white filament became a bit yellowish, like the white got too much heat and got burned a bit.

I printed with the same spool of filament before and got a very white result and the only thing I changed was the speed.

Has anyone encountered something like that?
I'm not sure I see why the speed matters for the color (does it change the heat the filament gets somehow?)

ABS white filament.
240 degrees on the hotend.
E3D V6 lite, bowden.

240 does seem a bit hot for ABS, did you try printing at slightly lower temps?

The filament should not receive more heat if printing faster, in fact it should be the other way around (in extreme cases you might not have time to melt it all the way through). May be something else going on, e.g. a thermistor that's loose and showing a lower temp than you actually have = more heat. I'd try reducing the temperature and printing again to see if you get the white again.

For what its worth I have a spool of white ABS on my printer right now that I print at 240c also like a dream without discoloring.
I print it at 40mm/sec

thank. I also always print 240 and never had such a problem.

Another print is about to finish in 3 hours. I printed it slower and it looks very white again,
I'll keep you posted once I get it out of the machine and compare it side by side.

Printing speed does affect colour, and its most likely because slower prints leave plastic in the hotend for longer. Check out Velocity painting by Mark Wheadon on twitter [twitter.com]

OK so the print is out and it seems the color is the same, so it rules out the printing speed.

My first guess would be as Anvoice wrote - thermistor not in place showing wrong temperature.
I hope it is not the case as V6 lite musn't get more than 245 degrees.
I'll get to it in the evening.

Any other thought? What may cause something like that?

If you have Black filament, you'll want to extrude with a lower temperature than you would with a natural "White" filament thermal resistance found in PLA and ABS. The necessary difference in temperature would be a few degrees (Celsius). However, there are many other factors, such as moisture and manufacturing techniques that can take precedence over color differences. (http://www.protofab.in)

Edited 1 time(s). Last edit at 02/11/2017 03:34AM by kairamatthew.

I think I proved it is not a matter of temperature.

I printed yesterday a white cylinder. starting 240 (deg-Celsius) and decreasing 10 degrees every 10mm down to 210 degrees.
Also printed average speed (2400mm/s)
The color came very uniform. There was not even a slight change.

Still a bit yellowish.

I find it hard to believe that it is a matter of old material, because I opened it out of vacuum less than a month ago and the prints in the beginning came very white.

So I still haven't figured it out.

... could be, there's a "bleacher" additive mixed into the filament, which is sensitive to temperature changes

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