Well Heck!
Been using my MK3s for several years with few problems. I upgraded the hotend with a Copperhead heat block and bi-metal heat break. I purchased a Bridgemaster nozzle all from Slice Engineering at the same time and this all has been working well. I added an MMU2S and after dialing the setting for tips, it's been working great.
Until... On an extended print I got an M112 Emergency stop called. That turned out to be the thermistor. So I ordered a Fystec three pack from Amazon and replaced the thermistor and I'm I'm back up and running fine.
Until... I get a really bad nozzle clog. I mess around trying to clean it up and just say "screw it", throw the nozzle away and install the Slice Engineering Bridgemaster.
Now I have terrible stringing, blobs and artifacts. All due I think to the Bridgemaster nozzle since this a problem I never ever had prior to installing this nozzle. I will add that I print mostly with PETG and have been doing so for a while.
Anyone care to share thoughts?
RE: Well Heck!
Higher the retraction speed of the extruder in slicer settings but it could also be the nozzle try a 20mm by 20 mm cube
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RE: Well Heck!
This is how I have my current settings.
RE: Well Heck!
I did print the cube and calibrate the extrusion. It was pretty much dead nuts.
RE: Well Heck!
I'm starting to wonder if the issue is moisture in the filament. Never been a problem before, it seems to match the symptoms.
RE: Well Heck!
The image in the first post to me looks like PETG that has to much moisture. Have seen stringing like that here, went away after drying the PETG filament.
RE: Well Heck!
You've made quite a few changes around the extruder.
You will understand that the standard profiles can no longer apply then.
So you will have to create your own profile in the slicer that are in accordance with the hardware you have changed.
RE: Well Heck!
Well, it's been running fine like that for quite a while until the nozzle change. I think I agree with Walter but I'm not sure why it wasn't a problem before. I've gotten an air tight chamber and have a few parts on the way. I plan to dry my filament in the oven and print with it in an air tight container with silica gel.
RE: Well Heck!
Dried the filament in the oven for about 3 hours. The printer is in a room with about 35% humidity. I made a filament storage box with an air tight bin that has a gasket in the lid and some ptfe tubing. added some desiccant and a hygrometer. Ran the print again with nearly identical results. I don't think moisture is the problem.
I plan to change out the nozzle this weekend.
RE:
I take it that the Brigemaster nozzle is correctly installed (i.e. no filament leaks form the heater block). Then the ‘culprit’ must be the nozzle, if anything else is changed and the filament is dry.
if your former nozzle was a regular brass unit, Bridgemasters are made from copper alloy and have better thermal conductivity, so you could lower a bit the nozzle temperature, which would help with stringing, but I don’t think that a couple of degrees would make a significant difference. The problem must be elsewhere.
Those retraction settings seem over the top to me, 6.2 mm, really ?. Bondetch recommends a retraction length equal to the nozzle diameter. A different thing would be Bowden extruders and/or very flexible filaments but for PETg, 0.4-0.6 mm should be OK. For instance, my current settings are : retract. length: 0.6mm. Z lift: 0.3mm. Retract.speed: 40mm/s. Deretrac. speed: 25mm/s. You could try a retraction setting of less than 1 mm and compare the result to what you get now with 6.2.mm. If there’s a similar amount of stringing, it’s not a problem of retractions.
Slice Engineering says that their Bridgemaster nozzle features a hard carbide coating to improve lifespan. Maybe this carbide has very low friction and the filament is more prone to ooze from the tip, specially with filaments like PETg. I’ve read reports of this side effect with diamond tipped nozzles.
RE: Well Heck!
I take it that the Brigemaster nozzle is correctly installed (i.e. no filament leaks form the heater block).
This!!!
Alright, rookie mistake here. Went to change the nozzle and it was loose. Tightened it up and recalibrated Z. Running a test print now but looks really good!
Thanks!