We all need to change filament from time to time, either because the reel we’re working on has run out or simply because we’d like to print in a different hue, or with translucent material, or print in wood. And if you’re like us, you’ve probably found that the first few layers of your first print with the new filament come out in the old filament.
So here’s our step-by-step guide to changing filament reels, to ensure you get a consistent print with the first new batch:
1. Heat up and wind out
Before you pull the old filament out, heat up your printer to its typical printing temperature, then turn the extrusion wheel to push a little filament out of the printer.
If you just try to yank the filament out when the machine is cold, you’re likely to snap it off in the print head and that could cause problems later.
2. Change the reel
Use the extrusion wheel to wind the filament back a couple of inches, then pull it out. You should find it winds back onto the reel easily.
Next, feed your new filament through the Bowden cable. You’ll be able to push it through manually for most of the way, until it hits the hot end, where it will stop.
3. Wind some more
Use the extrusion wheel to push some more filament through the print head, and you’ll see the old filament still squirting out. A surprisingly large amount of filament remains in the print head – or, at least, it seems that way when you’re squeezing it out.
4. Look for the change
As you wind the extrusion wheel, you’ll see the new filament starting to come through. At first it will be blended with the old filament, before it starts to show its true colour.
5. Keep on winding
Even though you’ve started to see the new filament colour, keep winding a few more turns to make sure none of the old filament is left in place to pollute the print.
Once you’re sure that what’s coming out is entirely the new material, you’ll be able to print with that filament without worrying about the old colour leaking through.