Pre-tear down print suggestions?  

RE: Pre-tear down print suggestions?

Look for the BELT TENSIONER PULLEY R1.stl in the Core XY assembly folder. I had to reprint one because I got the screw cross-threaded while working on the belt tuning, which caused the nut to spin in its seat. PCCF is the recommended filament, I used a very little non-sieze on the screw threads when I put the new part in.

RE: Pre-tear down print suggestions?

In addition to the recommendation above you may want to take a look at the Core One mods on Printables.  Several of the parts for the printer have been updated/upgraded by the community and some are much easier to install during the build.  For example I printed and installed these during my build:

Bed stop with heatset insert

Z motor mount with heatset inserts

One that came out since my build is an updated side filament sensor which purports to greatly reduce the force necessary to pass the filament through (for printing soft flex filaments).

Revised side filament sensor

I will be installing this in the near future as well as this upgraded Nextruder motor plate

Updated Nextruder motor plate

in conjunction with this mod, also intended to reduce the force acting on the filament sensor for flex filament loading

Nextruder filament sensor magnet mod

There are dozens more available to make your printer exactly what you want it to be.  Have fun!

Regards,

Steve

RE: Pre-tear down print suggestions?

Thanks, I'll definitely print a spare tensioner, and the insert bits.

I've got an MMU3 I am going to carry over as well, so I'm going to avoid nextruder mods for the time being.   (It seems to mostly work, and I seldom print flex's)

I'll browse around and see what I can find.   I'm not planning on tearing everything apart as soon as it gets here... 

David

RE: Pre-tear down print suggestions?

@david-holland - You might want to read https://forum.prusa3d.com/forum/prusa-core-one-hardware-firmware-and-software-help/core-one-crash-restart/ - I wish I had known about this at the time of the build...  

RE: Pre-tear down print suggestions?

Posted by: @bowtie6

@david-holland - You might want to read https://forum.prusa3d.com/forum/prusa-core-one-hardware-firmware-and-software-help/core-one-crash-restart/ - I wish I had known about this at the time of the build...  

In case you would like a TLDR summary;

I read the thread and the takeaway is to make sure that you remove a little of the powdercoating  on the underside of the XY frame at one of the screw locations for the mounting of the X and Y axis stepper motors. 

Several people had experienced phantom reboots of their machines on large prints and ultimately it was discovered that there was no ground path from the stepper motor housing to the metal frame of the machine.  It was surmised that belt movement on long x and or y travels caused a buildup of static which then discharged into the frame/wiring triggering a "power panic" response from the printer.  Everyone who has modified their printer to improve this grounding path reports that it has resolved the issue with their printer.

Regards,

Steve

RE: Pre-tear down print suggestions?

Yes, that's an interesting thread. I'd of thought one of the lines off the nema connector was ground but, I've never looked into it.

I'll have to keep that in mind.

Thanks for the heads up, appreciate it.

David

RE: Pre-tear down print suggestions?

Yes, that's an interesting thread. I'd of thought one of the lines off the nema connector was ground but, I've never looked into it.

I'll have to keep that in mind.

Thanks for the heads up, appreciate it.

David

RE:

Yes, that's an interesting thread. I'd of thought one of the lines off the nema motor connector was ground but, I've never looked into it.

I'll have to keep that in mind.

Thanks for the heads up, appreciate it.

David

RE: Pre-tear down print suggestions?

(Sorry for the duplicate post.   Apparently the forums rebooted in the middle of the post /s)

RE: Pre-tear down print suggestions?

The ground wire (with the NEMA connectors does ground the X-Y plate.  However, the motors sit on top of PCCF mounts and are fastened from below, through the mounts and the points on the powdercoated frame where the screws pass through are powdercoated with no masked areas to ensure motor grounding.

Regards,

Steve

RE: Pre-tear down print suggestions?

This would also come in very handy:  https://www.printables.com/model/1359251-ergonomic-organizer-for-fasteners-eg-for-core-one/comments

RE: Pre-tear down print suggestions?

Funny, Agreed, I am literally in the middle of printing thisaone...

https://www.printables.com/model/1351483-prusa-core-one-screw-organizer-customizable

I kinda dislike the "little baggies of screws sitting in a pile while assembling" from previous MK3 & MK4 kits.

RE: Pre-tear down print suggestions?

As a follow up, these were the things I printed (and used):

https://www.printables.com/model/1310752-core-one-z-motor_mount
https://www.printables.com/model/1295826-core-one-bed-stop-rear-heatset-insert-reinforced
https://www.printables.com/model/1227024-prusa-core-one-feet-v2-squashball-version-anti-vib

I printed a couple of BELT TENSIONER PULLEY R1, but did not need them, that being said, I don't think they'd hurt to have handy.
https://www.printables.com/model/1167816-core-one-printable-parts

This might be a better variation however: (I haven't used it, it just sounds reasonable from the description)
https://www.printables.com/model/1360563-core-one-belt-tensioner-pulley-to-take-a-threaded

I wish I had found these, and had pre-printed them:

https://www.printables.com/model/1275119-prusa-core-one-removable-z-splitter-holder     (Terrible serviceability design those standoffs, IMO)
https://www.printables.com/model/1212486-prusa-core-one-single-wifi-and-gpio-cover

A couple of screw holders: 

(Baggies were emptied into the appropriate slot in the screw organizer, as they were opened)
https://www.printables.com/model/1351483-prusa-core-one-screw-organizer-customizable

(And whatever I needed for the current step was removed from the organizer, and put into the parts tray...)
https://www.printables.com/model/1256558-parts-tray-for-prusa-core-one-kit

These are awesome: (IMO)
https://www.printables.com/model/1343702-core-one-z-axis-dust-protector

And lastly, I did print/use one of these to repack a little extra fresh grease in the recycled LM8UU bearings:
https://www.printables.com/model/32359-prusa-lubricant-lm8uu-adaptor-bearing-pacifier

I did do the grounding mod.    A couple of star washers on the motor mount screws.   Verified with a multi-meter. 

The precision homing is <ehm> "obnoxious"....   my printer seems to be one of the ones, it won't pass reliably unless the plate is at the top of the axis, but I've not gone so far as to physically bend anything as recommended by https://arachnoid.com/3D_Printing_Prusa_Core_One/   (Belts are dialed in @ 98Hz/92Hz w/ Spectroid, and the gantry seems reasonably square. Probably not square enough. <shrug>) 

I did add:

G90 ; Set to absolute positioning mode
G0 X1 Y1 Z1 ; Rapid move to X=1, Y=1, Z=1

As part of the Octoprint "before print job starts" GCODE.     It seems to have help for the whopping 4 prints I've done so far.    There's probably a place to do similarly in Prusa slicer as well. 

And lastly, yeah, turned off the door sensor in the settings.    It appears you cannot move axis's at all w/ it turned on, even when the printer isn't printing.    So if you've the door open, and want to lower the plate a bit, so you can wipe it off with a little alcohol, nope, gotta shut that door first, move the axis a bit, re-open the door, THEN you can wipe the plate down... <shakes head> Umm, no. 

I think it'd be a good idea if there were a "while printing" setting, that'd make the system only pay attention to the sensor while printing, but IMO, not while I'm at the controls. 

I think that covers everything I did that was different than documented.

Many thanks for everyone's suggestions, 

Cheers!

David