Printing ABS upon PLA

[veedee 4]

I want to try something that I can't find on the internet and this forum.

We all know that ABS printing requires an heated bed or so (I don't have one), but what if I put down some layers of PLA for the -sticking tot the bed- part, and go on printing with ABS upon the first PLA layers.

I was thinking to do this manually, like inserting a piece of PLA into the extruder, and right after that insert the ABS filament. While printing, I manually tune up the temperature of course.

Someone tried this before? Does it work? Or will it ruin the print(er)?

 

[joergen 2]

The heated bed for ABS is mostly to keep the ABS near the glass transition temperature, since it will shrink more when it cools down to room temp. printing PLA first doesn't change any of the shrinking/cooling related properties of ABS.

 

[nick-foley 5]

This definitely works. I've used the same technique to get a variety of materials to stick to the bed.

One reason I'm excited to get a dual extrusion kit from Ultimaker is to have PLA + another material in my machine, so that I can always print a few base layers of PLA and then print whatever else I want on top and not have to worry about bed adhesion.

Of course, like Joergen says, you still need to have your print settings tuned to the material you're going to be printing in, but for many objects and materials, the burden of getting it to stick to the bed is 80% of the problem, not getting it to print correctly once it is actually stuck.

 

[othar 0]

it's strange because in general, ABS didn't stick well on PLA. It's often use (when you use dual extruder) to print ABS model with PLA support. The PLA can be easely removed from the ABS.

 

[nick-foley 5]

I think the copolymer mixture that happens as the two filaments blend in the nozzle is probably why it is sticking so well.

Dual extruders probably wouldn't produce that sort of mixing, now that you mention it. Still, it will probably be similar to creating a micro-heated bed whenever you print the first few layers as an adhesion layer.