Brassfill jamming
Hi,
I'm having trouble with Colorfabb BrassFill.
What happens is that when I switch from PLA to Brassfill, it works fine for a few seconds, then the flow peters out and stops and that' s it - the nozzle is jammed. I have had to take the whole hot end apart twice now and clean it out fully before restoring the ability to print. It is billed as 'printing like PLA'.
I have installed the hardened steel 0.4 nozzle from E3D. After jamming I have tried cold-pull clearing with PLA and ABS and flushing with ABS, but with no luck.
What am I doing wrong? 🙁
Re: Brassfill jamming
You may need a bit more heat. Have you tried regular PLA with the steel nozzle?
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Brassfill jamming
Thanks Peter,
I've been printing PLA and ABS with the hardened steel nozzle with no issues.
What I find weird is that it starts printing okay, then chokes up after 10-20 seconds.
Maybe I should try printing faster or slower? I was thinking maybe the heat from the hot end would travel much better back up the filament and into the start of the cold side, given the material is 80% metal?
Re: Brassfill jamming
Print very slowly (30mm/s max) and if you are using retraction, make retraction speeds slow (10mm/sec) as well.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Brassfill jamming
"Oh brass, how do I love thee? Let me count the ways"
So. To ensure that this wasn't down to defective parts I replaced the heat break, PTFE, thermistor and steel nozzle - all to no avail.
Then I realised that it might be the steel nozzle itself. Turns out steel has a much worse heat conductivity than brass, so the nozzle is unlikely to be as warm as a brass nozzle at the same 'temperature' as measured in the heating block by the thermistor. The fresh filament coming in cold will draw heat which is not so quickly replaced. So the suggestion to print slower is a good one, although this made no real difference to me (not a scientific conclusion). Maybe a higher temperature would help.
Then I read up about brassfill, which is 80% metal. Of course this means the filament will conduct heat much better than normal PLA. This can cause the heat to travel back up the heatbreak causing sticky filament higher up. The solution? Print quicker. And keep things as cool as possible.
Oh. Hang on...
So I'm thinking I might just buy a job lot of brass nozzles and consider them a consumable. o_O
Unless anyone has some working settings for the E3D hardened steel 0.4 nozzle plus BrassFill?
Re: Brassfill jamming
Try a faster print speed *and* a higher nozzle temperature. You want the nozzle temp to be high enough for the filament to melt quickly, and the speed to be high enough to push the filament through before the heat travels back up. It's all a function of time.
I haven't gotten my hands on any brassfill yet otherwise I'd run my own tests. 🙂
Re: Brassfill jamming
Get some! When it works it is GORGEOUS. 🙂
Re: Brassfill jamming
Get some! When it works it is GORGEOUS. 🙂
How are you finishing it in post?
Re: Brassfill jamming
So far I have been hand sanding it down with grits from 240 to 7000. I haven't tried wire wool yet. Brasso did not seem to improve the finish beyond what I achieved with 7000 grit. Bit of elbow grease. Comes to a high golden shine with only a few flecks of non-metal remaining. No power tools.
I might built a little tumbler too as that seems to work a treat as long as you don't mind prominent details being worn away.
Re: Brassfill jamming
Interesting. So how do you sand areas that are detailed or hard to reach? I thought that is what tumbling media excels at.
Re: Brassfill jamming
Omicron - the items I have been printing haven't had hidden crevices so sanding has worked a treat. I suspect I would employ files and wire wool, though I might make a little tumbler. I am just a bit worried about the external details - in many photos I've seen, the print loses a lot of definition after tumbling.
Re: Brassfill jamming
UPDATE
As a last resort, I tried a 0.6 hardened steel nozzle (from E3D), and a brass 0.4. Both failed to help.
I discussed with ColorFabb briefly and I think I understand the problem now. BrassFill likes to keep moving through the print head. So it is okay with large solid objects where it can keep pumping the filament through, but not so good when there are multiple small objects, or patches on a layer. Then the filament slows down because of lost printing time while the head moves, plus the constant retractions work against the outward flow. This causes the two killer problems with BrassFill: (1) holding the material in the hot print head causes separation and deposition of the brass inside the nozzle and (2) heat can travel back up the filament (as it is 80% metal) causing it to melt above the heat break and clog there.
So it is not print settings per se, but WHAT YOU PRINT that can make it fail...