Setting an unbeatable record: NO flush at all :)

So I got the idea to print a silly dragon just to try some dual color filaments. I used three different such filaments, so two filament switches at thirds of the total height.
Then I got the idea that if I’m using dual color filament anyway, why flush at all?! So I set the flushing multiplier to zero as well as removed all flushing from the Change Filament G-code. Not sure if the latter was superfluous with a zero multiplier.

Printing now, I’m going to bed. Will post pictures of results tomorrow.


So a bit late…

I can’t spot the exact points where the filaments switched (and the print was basically flawless). Chances are they ended up in infill (or the prime tower? But it’s just 3.06 g in total). This experiment had the side effect that it shows the two “Bambu PLA Basic Gradient” filaments are mostly just silly pastel colors (actually I think they do shift, but too slow for this model) while the “Bambu PLA Silk Dual Color” was closer to what I expected (and also close to the DIY dual color filament I tried, which worked much better than I expected although 45g is a bit too little - I think it could be double that on a print bed.

But my experiment also proved that the idea worked as expected: When looks doesn’t matter (or shifts are even wanted) we can turn purging off entirely. Maybe we should have an option for it in the slicer. Or maybe just setting the multiplier to zero would be sufficient, without editing any G-code. I need to try that for completeness. I think I will just use black and white, and print a small vase in spiral mode so the swicth is easier to find.


On a different note I have this idea for a cheap KISS filament joiner with (I hope) perfect welds quick’n’easy: Just take a small heatsink (about the same size as a hotend one) with more than 2 mm thick “base”. Drill a 1.8 mm hole in the base (actually I will try 1.75 mm first) and stick two pieces of filament in there so they meet in the middle. Heat the heatsink to 250°C with a torch, soldering iron or whatever, then let cool (or help it cool) while gently pushing both filaments inwards. Done. You need to use short(ish) strands since this construction will require you to pull one end out through that hole - there’s no slot for taking it out sideways. The upside of that is the welds should be perfect in terms of size/shape.

I’m pretty sure that would work fine, and very easy to use with a really good success rate. I’ll keep you posted.

If it works well, I’ll probably mount a Bambu heater and thermistor on it and build a trivial circuit for keeping it at 250°C when a button is pushed, or something like that. And a fan? lol

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we tried something like this too, where we were ok with the filament sort of gradually shifting from one colour to the next
we even turned off the priming tower since it wasn’t necessary, and iirc this model doesn’t have infill? (its one of the lamps from the bambu store).
zero flush, no waste, but we still couldn’t really see a blend where the filament changed. this was with standard bambu matte filaments, not gradient or dual colour ones