E3D V6 nozzle vs MK8 nozzle, first layer adhesion

  • Does anyone notice that when they upgrade from an MK8Makerbot(?) to a E3D V6 hotend that when using the same settings and bed-leveling/z-distance-setting procedures, that the filament is much more likely to be pulled up and bunch up around the nozzle while printing the first layer?

    It occurs mostly when printing small details, such as 3 mm bolt holes, and not so much when laying down long lines.

    Is this due to the shape of the nozzle, which on the V6 is much more flat when compared to the MK8 which is more sharp, or is it due to something else that can be easily fixed?

    e3d nozzle
    mk8 nozzle

    what kind or Mk8? Mk8 is a way to show that this is *itteration 8* of some hotend. Who's manufacturer? which design? On which printer?

    It seems there are unspoken rules that you are supposed to follow when switching to an e3d v6 or other all metal hotend. People say to increase the temperature 10-30 degrees and the bed temp as well. I dont see how this should matter if both thermistors are accurate. All I know is after installing the V6 and keeping everything else the same, the filament is much more likely to get pulled up and stick to the nozzle!

    @Trish good points, I thought the same thing; but I don't think that's how it works. Everyone simply calls them "MK8". Search Amazon for "MK8 nozzle" and you will get this specific shape of nozzle and a specific thread type

  • When filament curls up this generally means that there is some sort of obstruction or burned material in the nozzle causing uneven flow. You can use the Atomic Method from this answer.

    Burned residue in the nozzle

    Being a new nozzle, I would expect that this is not the case, so that it should just drop out of the nozzle and not curl up. It could be that the nozzle is not perfectly machined and a defect in the geometry is causing this. You could try to replace the nozzle with another nozzle. They are pretty cheap, you should buy a few extra.

    As far as why the filament sticks easier to the E3D nozzle when it curls up, is that this nozzle has a (hexagonal) flange that sticks out, while the other nozzle does not have such a flange. If it curls up, it has a larger probability to hit the flange and stick to the outside of the nozzle than a nozzle that has no such flange.

    even if perfectly machined, a burr might exist that acts as a deflector (deburring is sometimes skipped on cheap products)

    Tried two of the same type of V6 nozzle- a stock one and a hardened one. In both cases they pull the edges of the test cube up off the bed after a few layers. Never had a problem with these 1cm square test cubes adhering with PLA to a 60 heated bed before with the stock MK8 hotend nozzle. Now I have to add hairspray if I want them to stick. (or increase temp and flow much higher)

    @cds333 So you have an adhesion problem, not a filament curl up. This answer explains why the filament curls up when it leaves the nozzle while priming at height. For adhesion problems play with the bed to nozzle distance, or use a PVA based adhesive.

  • Turns out this can be fixed by increasing the bed temp to 65-70 °C and of course increasing the extruder temp by 30 °C or so, which is standard for the all metal hotends (no idea why)

    Please accept your answer and explain why an all metal hotend requires an extra 30 °C to run filament, or reference to this statement, this doesn't sound logical. Accepting the question prevents the question to be bumped to the top of the queue once in a while, thanks!

    Have you measured the temperature of the two hot ends with an actual thermometer or are you just going off the print settings? The thermistors used to measure temperature can have wide tolerances and your V6 might actually be running colder than your original hot end with the same settings. Plus, is your V6 a real E3D or a clone? All-metal hot-ends have much stricter machining/material requirements for the internal throat and heat-break than the ones using a ptfe liner, and some of the cheaper V6 clones have inferior thermal characteristics compared to the E3D originals.

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Content dated before 7/24/2021 11:53 AM