Bowden wheel grinding noise and failure to load material


Hi Guys and Girls,

I was printing a 24 hour long print and was 20 hours into said print when Failure occured,

I pre oiled all sliders and foam pads, making sure all was well for the long print time. I did think there was enough filament to complete the job. at 84% I checked the filament and decided to carry out a material change pla white for pla black (flux branded too)

I paused the machine and selected change material (load unload) succesfully unloaded the white pla.

After holding the spring loaded button down I manually fed the filament through the Extruder tube until it was 70% down the tube.

After pressing load (the plastic was sharp at the end…) it reached the hot end (the hot end was definitely HOT.

no plastic seemed to ooze out the extruder. I have used the pin to clear it but am yet to solve the problem.

The machine is currently upside down waiting for a Bowden wheel check and clean… Not exactly a convenient thing to get to…

Any tips on improving the odds of this printer not ending up in the bin any time soon would be gratefully received.

The whole Flux experience is problem after problem… ZORTRAX are incredible machines and since ordering the Flux Zortrax is an open machine to third party materials. Happy days


Hi, this should be your filament and positioning of the filament, if your filament amount is too low then the is a chance this will occur, you should try using a new filament roll, hope this helps, Thanks!


I thought i made it clear i was changing old for new (fresh out of vac sealed flux pla bag)

Im familiar with the process. Im just incredibly dissapointed with the delta plus


I think I know what you are talking about. I found that when you remove the original filament, a blob is left in the tube and then when you feed in the new filament it gets in the way so you cannot push the filament all the way into the printhead. You will need to remove the tube from the printhead and pull out the little blob. At least this is how I fixed it for myself.


Hi @Mattman

This does make a lot of sense as filament removal was a little jerky. I think this is due to the molten plastic mushrooming as it comes away. I think I will be placing the new reels slightly higher so I can grab the filament quicker as it comes out. A similar thing happens with the Zortrax to be fair but its a far more accessible unit. I decided to do a multi layer print soon just to nail the flakey material change. I’m thinking to cut away a partial section of the tube near the print head so you can get to the filament quicker too.

Cheers Mattman


Well I checked right down the bottom of the filament tube…Lets just say there was a microscopic piece of plastic just big enough to stop the filament entering the hot end. I have stripped it down and cleaned it all up and hopefully everything will run a little bit more smoothly from now.

Thanks again for the heads up


Glad you got it figured out… it’s annoying when that happens! :wink: When I do a filament change or load with mine, I usually bypass the self-loader stage by feeding the filament by hand all the way down the tube and into the head… I push it all the way in until it stops, move it to make sure it is actually in the head, and then pull it back about an inch so it’s still in the head, and then let the delta do the last bit on it’s own. It’s a lot quicker that way, and also makes sure that it doesn’t jam on either on the quick-release couplers.