3D printer training Saturday 25th September

[Simon Hewison]

I know this is short notice, but I'm going to be in the space tomorrow (Sat 25th September) about 13:00, and can do some 3D printer training.

Sign up, as usual, on the wiki :
https://wiki.london.hackspace.org.uk/view/Lulzbot_Mini_Training

Due to the limited amount of space in the room, and because it's still a good idea to keep socially distanced, I'm going to run two sessions, with a limit of one inductee at a time.

Advanced notification has been given to those who have already expressed an interest on the wiki, but two of them have said they can't make tomorrow.

Training cost: £5.00 per head.

further maintainers / trainers welcome. I don't get to come into the space that often due to having moved out of London. Please express interest below.

[Aidas Baltušis]

I've recently been inducted as a maintainer for the 3d printers. I'll come have a chat tomorrow :)

--
You received this message because you are subscribed to the Google Groups "London Hackspace" group.
To unsubscribe from this group and stop receiving emails from it, send an email to london-hack-sp...@googlegroups.com.
To view this discussion on the web, visit https://groups.google.com/d/msgid/london-hack-space/c201a356-edbe-4a58-9ce7-0939afdf0644n%40googlegroups.com.

[Mauro Vilasi]

Hi Simon,

missed this one - I've used 3d printers before but I'd be happy to do the training to be able to use the ones at the hackerspace.
So, just registering interest for the next time.

Cheers,
Mauro

[Juraj Oravec]

Hi, I've joined recently and would be interested in the induction the next time there's one :)

[Adrian Godwin]

If this is the thread to say so, I'd also like to join an induction session at some point.

To view this discussion on the web, visit https://groups.google.com/d/msgid/london-hack-space/2e99f654-f807-41c3-8e57-55725f68b62cn%40googlegroups.com.

[Adrian Larumbe]

I'd also be interested.

>>>>> <https://groups.google.com/d/msgid/london-hack-space/c201a356-edbe-4a58-9ce7-0939afdf0644n%40googlegroups.com?utm_medium=email&utm_source=footer>
>>>>> .

>>>>>
>>>> --
>> You received this message because you are subscribed to the Google Groups
>> "London Hackspace" group.
>> To unsubscribe from this group and stop receiving emails from it, send an
>> email to london-hack-sp...@googlegroups.com.
>> To view this discussion on the web, visit

>> https://groups.google.com/d/msgid/london-hack-space/2e99f654-f807-41c3-8e57-55725f68b62cn%40googlegroups.com
>> <https://groups.google.com/d/msgid/london-hack-space/2e99f654-f807-41c3-8e57-55725f68b62cn%40googlegroups.com?utm_medium=email&utm_source=footer>
>> .
>>

[Simon Hewison]

Very low-key training session might be occurring tomorrow (23rd October) afternoon.

This is dependent on me first of all getting to the space (I now live well out of regular distance)

I've also been told verbally third-hand that the 3d printers aren't working, so I'll need to address that first of all.

If you happen to be in the space tomorrow afternoon, find me and ask me if it's possible, but don't go making trips to the space just to learn about 3D printing.

[Claude]

Hello Simon, 

I had a look at the printer yesterday. Both printers seems to have stuck filaments.

Crump filament has been broken or cut flush. You can't grab it by hand to retract it. And pushing it down with a new filament didn't work either. 

For both Crump and Hull the extruder teeth have been grinding up the filaments, so there is not enough grip to either extrude or retract, even after proper heating of the nozzle.

I've not tried to unclog them with a needle.

Kind regards,

Claude

[Simon Hewison]

Grinding extruder drive teeth does indeed sound like there's something in there that's blocking. You did the right thing to crank the extruder temperature up, since you have no idea what filament has been left in the extruder or hot-end.

The Aerostruder-equipped printer (crump) should be easier to clear because it's got a straighter filament path to the nozzle than the Lulzbot standard extruder (on Hull).

To clear it out, if the extruder motor isn't able to push it through,  disengage the extruder (aerostruder needs you to squeeze the Idler towards you, the standard lulzbot extruder you can just uncouple the  crank up the hotend temperature really high (above the regular temperature for ABS - 260ºC or so) , wait for it to warm up (ideally at this point, there should be oozing plastic from the nozzle), and then using some PLA filament, push it into the extruder, past the hobbed bolt of the extruder motor gear, and see if you can encourage filament to come through.

poking it with needles or bits of metal is problematic, as there's the potential in the Lulzbot design for the power from the hotend heater (24V) to come into contact with the max 5V input to the microcontrollers used for the Z-axis minimum endstop contact which is the nozzle. Filament should be enough to encourage it through if the hotend is hot enough.

pictures of the inside of the Aerostruder assembly are at: https://ohai.lulzbot.com/project/lulzbot-mini-2-aerostruder-assembly-and-packaging/hot-end-tool-head-assembly/
pictures of the inside of the standard Lulzbot extruder assembly are at https://ohai.lulzbot.com/project/mini-104-extruder-assembly/hot-end-tool-head-assembly/

If you manage to unblock it, congratulations! You win a prized '3d printer apprentice maintainer' badge.

If not, then you may need to get a bit more medieval and start tearing it down, removing the nozzle, cleaning the nozzle with solvents, etc, and re-assembling. This involves very hot things and holding hot metal things carefully near your hands. That is beyond the scope of the advice in this email. That takes quite some time.

Tip for anyone using a 3D printer where you need to manually load and unload filament (some fancy models can auto-load and unload filament - the Lulzbots can't) : never just snip the filament near the input to the extruder drive. Bring the temperature up and retract the filament until it comes free. Just snipping it does make removing what's left for the next person rather problematic. Last time I was in (which isn't very often these days), both of the printers had silly little stubs of filament cut near the extruder inputs.

[Simon Hewison]

note : although I've had a report that both the Lulzbot 3D printers are currently unusable, due to the lack of maintainers, I haven't put them out of service, because clearing blockages is something that a regular trained user should be able to attempt. I have however updated the status on the 'Tool status' page.
https://london.hackspace.org.uk/members/tools.php