RE: Prusa CORE One kit assembly instructions
I just had an issue with the nozzle scratching my heat plate in the far left corner. The cable cover for the heat bed was raised too much, so that the Nextruder fan shroud would touch the cover before the nozzle would touch the bed. I assume this messed up the meshing algorithm (some interpolation of the exact bed coordinates, I guess?).
Anyway, the reason for the raised cover was clearly the M3x10 screw (cylinder head) installed according to the instructions. I exchanged it with a spare "rT" screw of the same length. Maybe someone can check and confirm this. You can move the Nextruder into the far left position and see if the nozzle can touch the bed or not. This may require to rotate the Z-rods by hand.
RE: Prusa CORE One kit assembly instructions
I just had an issue with the nozzle scratching my heat plate in the far left corner. The cable cover for the heat bed was raised too much, so that the Nextruder fan shroud would touch the cover before the nozzle would touch the bed. I assume this messed up the meshing algorithm (some interpolation of the exact bed coordinates, I guess?).
Anyway, the reason for the raised cover was clearly the M3x10 screw (cylinder head) installed according to the instructions. I exchanged it with a spare "rT" screw of the same length. Maybe someone can check and confirm this. You can move the Nextruder into the far left position and see if the nozzle can touch the bed or not. This may require to rotate the Z-rods by hand.
It's really close on my Core One build, but the nozzle touches the print sheet just a hair before the fan shroud touches the cable cover -- 0.1 mm according to my feeler gauge. Mental note: Don't use a thinner print sheet!
Did the cylinder head of the original M3 screw protrude over the surface of the cable cover? It doesn't do that on mine; it sits flush or even slightly recessed.
RE: Prusa CORE One kit assembly instructions
My description was not very clear, sorry.
I am talking about the single screw (under the top cover), which sits so high that the top cover slightly bulges outwards. This screw fixes the bottom part of the cover to the heatbed. A smaller screw head helped to lower the top cover.
The two screws further back (connecting both parts of the cover) are not an issue, they sit flush with the top cover.
RE: Prusa CORE One kit assembly instructions
I am talking about the single screw (under the top cover), which sits so high that the top cover slightly bulges outwards. This screw fixes the bottom part of the cover to the heatbed. A smaller screw head helped to lower the top cover.
Ah, thank you! I noticed that my top cover was bulging slightly (just by feel, it's hard to see). But assumed that it was due to the tight fit of the cables underneath, with the design cutting it close because of the limited space. Since it did not cause a collision on my printer, I did not investigate further. But I will open the cover now and replace the screw to get this sorted.
Thank you for the hint! Deserves to be highlighted in the build instructions -- could you add comment?
RE: Prusa CORE One kit assembly instructions
A little non-technical tip: While I did not find a way to do a full-text search in the online assembly manual, you can download the PDF version and search there. Yes, that's pretty obvious once you re-visit the starting page of the instructions and notice the 'PDF Download' button...
Why would you need a full-text search? Well, in my case I found an M3x6 screw in the bottom of the Core One enclosure, and wanted to see all the places where it might have come from. (Turned out that it was meant to hold one of the rear mounting blocks for the Y rods -- strange, since I tend to err on the side of over-tightening screws. Maybe I forgot to reset that one after I had loosened the Y rod on one side to get it parallel with its counterpart?)
Oh, and another suggestion: Add a guitar plectrum to your Core One toolkit, or one of those plastic "spudgers" you get with mobile phone repair kits. Makes me feel much better about prying out those plastic rivets without scratching the panels.
RE: Prusa CORE One kit assembly instructions
The X/Y homing still bangs the Nextruder into the front right corner several times, but I assume that is deliberate, to obtain a more accurate home position? Not entirely sure why they need that to be so precise -- is it just to enable resuming after a power outage? If so, I wish I could turn the "accurate homing" option off. Power outages are not a concern here, while the banging is annoying me on every print...
My MK4 and MK4S both do this from time to time - the x-carriage bangs the left side and the y-carriage bangs against the back, sometimes one or the other, sometimes both, sometimes up to 50 times(!). Like you, I could see no reason why it needs to know the origin so precisely. I hadn't considered the option to resume after a power outage, but like you that's a feature I will virtually never need, and in fact I find it more of an annoyance because toggling the power switch isn't enough to get out of a messy situation because it tries to carry on where it left off!
Also, if the programmers have decided that it needs a few goes that are all within a certain tolerance, regardless of what I think of the tolerance value they've chosen I can see no reason why my printers occasionally take so long to get a satisfactory result, and other times they sail through. They don't appear to be hitting anything, and the belt tension seems fine. So I'll add to your call to make this a configurable option.
RE: Prusa CORE One kit assembly instructions
Apologies if this has been asked/answered. Just got my kit. The boxes are mostly numbered 1-11 or so. What is in box 6? I don't have a box six.
RE: Prusa CORE One kit assembly instructions
Same here, no box #6. But two of the boxes are unnumbered, the motor kit (taken over from the MK4 printer) and the straight rods. Maybe one of them is considered box #6 in Prusa's packing logic, and just does not have a corresponding label?
RE: Prusa CORE One kit assembly instructions
Same here, no box #6. But two of the boxes are unnumbered, the motor kit (taken over from the MK4 printer) and the straight rods. Maybe one of them is considered box #6 in Prusa's packing logic, and just does not have a corresponding label?
Yeah that was my guess also. Support had no idea any of the boxes were numbered lol. Cheers Jurgen
RE: Prusa CORE One kit assembly instructions
Thank you for writing your observations from the construction here in the thread and some of them are already in the manual. I didn't know that and I was pleasantly surprised that the comments that were written in other languages are "transferred" to the Czech manual. Prusa deserves praise for that, good function
I am from the Czech Republic, I don't speak English, I translate using Google Translate
RE:
So here are my first impressions of the Core One kit.
I had a lot of fun assembling it and everything went well with the exception of the USB stick not being detected (which was my fault)
After I contacted the support (who were really great!), we found out that the black ground cable on the LCD was not plugged in correctly
After that everything worked again.I also had the dreadful humming noise when driving the Z axis at high speed. I also sent a video of this to the support team.
They also advised me to grease the spindles. I then greased them minimally over the entire length (applied with cable ties) and then everything was fine again.
So far, I can say that I have no complaints about my first printed parts. I first printed the classic Benchy and did a fist layer test.
Everything was perfect. Then I printed a tolerance test and planetary gear.
The only point of criticism so far was some ghosting on the Z-seam of the gear.
But otherwise no VFA's to recognize so far.
Even if it actually looks like VFAs can be seen in the one picture, this is due to the image. In real life, the surface looks as smooth as butter.
The Benchy was printed with the 0.2mm speed profile and everything else with the 0.2mm structural profile. After the shrinkage compensation in the Califlower test, the results are very satisfactory for me. Skew is virtually non-existent.
To sum up, I have to say that I am very satisfied. As for the loudness in normal mode, this is absolutely ok for a CoreXY printer. When I leave the room and close the door, the printer can no longer be heard in operating mode.
I think the new function with the filament retract is great, but is it normal that the nozzle still heats up when unloading?
RE: Prusa CORE One kit assembly instructions
Congrats on the builds and printer. Thanks for sharing your results.
--------------------
Chuck H
3D Printer Review Blog
RE: Prusa CORE One kit assembly instructions
I just had an issue with the nozzle scratching my heat plate in the far left corner. The cable cover for the heat bed was raised too much, so that the Nextruder fan shroud would touch the cover before the nozzle would touch the bed. I assume this messed up the meshing algorithm (some interpolation of the exact bed coordinates, I guess?).
Anyway, the reason for the raised cover was clearly the M3x10 screw (cylinder head) installed according to the instructions. I exchanged it with a spare "rT" screw of the same length. Maybe someone can check and confirm this. You can move the Nextruder into the far left position and see if the nozzle can touch the bed or not. This may require to rotate the Z-rods by hand.
Yeah, please add this as a comment to the instructions at the respective step and/or contact Prusa support about this - I think there are a lot of users out there (including me) who want to use their powder-coated textured sheets and they are slightly thinner than the standard smooth PEI one.
It would be awesome to have an advice from Prusa how to handle this topic!
Thank you all for your contribution here - I can't wait until the FedEx courier is dropping the long awaited parcel at my doorstep tomorrow 🙂
RE: Prusa CORE One kit assembly instructions
I did talk to support and added it as a comment to the assembly manual.
Yeah, please add this as a comment to the instructions at the respective step and/or contact Prusa support about this
RE: Prusa CORE One kit assembly instructions
I did talk to support and added it as a comment to the assembly manual.
Yeah, please add this as a comment to the instructions at the respective step and/or contact Prusa support about this
And what was support's reply?
RE: Prusa CORE One kit assembly instructions
Inconclusive? 🙂 We didnt find anything out of the ordinary on my printer. They wanted to move this topic to the "experts" and would let me know if anything comes out of it. Havent heard back yet. That is why I asked if others hat the same (potential) issue.
RE: Prusa CORE One kit assembly instructions
There is also a tiny bit of play in positioning the fan shroud. If you push it upwards while tightening its two mounting screws you can probably gain another 0.1 mm or so. But Prusa's tolerances on the screw holes are pretty tight, even (or especially?) in the printed parts, so there's not a lot of headroom to be gained.
RE: Prusa CORE One kit assembly instructions
There is also a tiny bit of play in positioning the fan shroud. If you push it upwards while tightening its two mounting screws you can probably gain another 0.1 mm or so. But Prusa's tolerances on the screw holes are pretty tight, even (or especially?) in the printed parts, so there's not a lot of headroom to be gained.
I will mount anyways a Silicium carbide or tungsten carbide nozzle - and they are actually a tiny bit longer than the stock HF nozzle - so this could also come in handy 😀
RE:
The only point of criticism so far was some ghosting on the Z-seam of the gear.
But otherwise no VFA's to recognize so far.
Even if it actually looks like VFAs can be seen in the one picture, this is due to the image. In real life, the surface looks as smooth as butter.
The ghosting at the seam is surprising to me. Doesn't the seam essentially come from excessive filament being squeezed out where the beginning and end of the trace overlap? I.e. there is no real radial movement of the print head, right? So why would ringing occur?
In any case, congratulations on the VFA-free prints! Now if we could only figure out the underlying difference between a Core One with and without VFAs... Just a lucky draw with the XY stepper motors, so they run smoothly even without phase stepping compensation? Or belts which happen to run perfectly centered, avoiding contact with the idler flanges?
RE: Prusa CORE One kit assembly instructions
Now if we could only figure out the underlying difference between a Core One with and without VFAs...
I wonder if moving the belt position on one stepper some number of teeth so its rotor tooth relation to the other stepper syncs up. Is your gantry trammed (runs square)?
Also, in the VFA thread I mentioned an odd behavior I noticed:
- After homing, running the y-axis into the front stops is as one would expect (no x-axis movement)
- Then running the y-axis into the back stops causes the print head to jump to the left (-x)
- Now running the y-axis into the front stops causes the print head to jump to the right (+x)
This is just using the y-axis move function and turning the control knob, and one doesn't need to bump the stops hard (a single notch of movement in the control knob will cause the jump). I can write up some g-code to automate it and post a video if that would help.
But otherwise no VFA's to recognize so far.
Would you mind trying the above procedure? If touching the y-axis stops does not make your print head jump in the x-direction, perhaps it's a useful test.