1 Topic by GoolGaul

  • GoolGaul
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Topic: ABS --> PLA --> ABS

Hey all,

Until now, I have been printing exclusively in ABS.  I think I want to do some PLA prints as well.

I've seen the differing temperature requirements of the 2 materials, and it got me wondering how you would switch from one to the other.  wouldn't the higher ABS temperature burn or liquify the PLA?  WOuldn't the lower temps for PLA not even melt ABS?

I haven't seen much info on this...

2 Reply by IanJohnson

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Re: ABS --> PLA --> ABS

They can meet in the middle around 190.  Just don't keep PLA hot for longer than necessary.

3 Reply by GoolGaul

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Re: ABS --> PLA --> ABS

ahhh, why didn't I think of that?

How much filament needs to be extruded to "flush" out the previous material?

I would think that small remnants of PLA would liquify leaving some inconsistencies in the ABS, and conversely, small amounts of ABS could clog the nozzle at lower PLA temps...

4 Reply by IanJohnson

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Re: ABS --> PLA --> ABS

I usually do a straight 100mm shot.  If you are following a dark color with a light color, it might take more than that.

5 Reply by solijohn

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Re: ABS --> PLA --> ABS

IanJohnson wrote:

I usually do a straight 100mm shot.  If you are following a dark color with a light color, it might take more than that.

We use a bit more in the shop. Perhaps 500mm, just to be sure.

Former Solidoodle employee, no longer associated with the company.

6 Reply by Gordym

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Re: ABS --> PLA --> ABS

I agree. 100mm does not clear the old stuff when I change my filament. I set my first blow out at 300mm, then reset it to 100 and run that until the new color is close to what it is supposed to be.

SD2
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MK5 V6

7 Reply by GoolGaul

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Re: ABS --> PLA --> ABS

yeh, I print black ABS, but I will probably be using either white or natural (?) PLA.