All fixed up, I am going to print and test the 23.5mm core before I release the 25mm parts just in case I missed something else.
So 9+hours.
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Does this mean “core” and “gantry clamps” - or “core clamps” and “gantry clamps”?
I think it is “core” and “core clamps (that go on the gantry)”. 
The 9 hours print time confuse me though. That’d be a fast core. 
I was hoping he is referring to the clamps… I’m all out of the light color used for the core. Perhaps some kind of makeshift adapter can solve it… or maybe I should just get some more PLA of the right kind.
I printed 3 well actually 3.5 cores I have an eclectic primo
Well I am updating the Core, Core clamps (While these are different I do not think they are noticeably different, the largest error was on the core), core Z clamps (I do not believe these changed but I am updating them just to be safe as they are part of the same model).
My core prints in 9 hours (0.5mm nozzle), and the other parts will be printing on other printers.
If you have a 25mm core, a user made modified core clamps that will make it work as is ( I think), https://www.thingiverse.com/thing:4564508.
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Is this error on one or several clamps?
None.
But if you want to use the core with the errors you will need 4 of the modified clamps.
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I saw those in another thread. I think losing 1.5cm of space is not an issue for me with 55x75cm workspace at the moment and it is a lot cheaper than printing a whole new core. Plus less shouting at the kids if they go near it while printing a core.
Did anyone else try those modified clamps?
/edit: @vicious1 You didn’t seem too happy with the modified clamps because of the missing Y clamp. Do you see the possibility of altering the Y clamp the same way the others have been altered as a quick and dirty fix for those who don’t want to reprint the core?
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Yeah - I just checked the PLA leftovers, and I don’t have anything at all left for sticking to my color combo, not for a new print, nor only the clamps. Well well - function over beauty!! Would the modified clamps provide the same mechanical precision in the end product?? (other than loosing 15mm)
In the other thread the guy says it did help him and his friends as far as I understood him right.
Just finished printing the regular clamps today and the rails are loose. I m going to try the modified clamps as well.
I have got like, 10g left. -_- So either I print them red like the core or I’ll wait for my filament to arrive. I ordered black, yellow and white. I could add some white for the Schneewittchen theme. My daughter criticized me anyway because only the table was white.
I am going to try and figure that out. It is not an easy cut and without the actual build here I can not be sure it is correct. So I have to wait and finish the “C” version and see how it differs. I am not sure that will even work for smaller parts.
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Several hundred posts above I posted that I started the Primo F update with printing one of the trucks.
The second part I printed was the core and the result was quite bad, small layer shifts and a bad impression in general.
I thought of reprinting immediately but I decided to print the remainig parts first and had hope the core is functionally fine.
But I was not happy at all, because the new machine should not only work fine but also look nice.
I suffered from bad print quality since some time, but not always. Means sometimes it is quite decent, sometimes bad.
More or less by accident I found out that it was due to the use of OctoPrint.
But not OctoPrint was to blame, but me using it on a Raspberry Pi 1. I had it at hand and at the time, when I wanted to give OctoPrint a try, I found no posts or something that this is not a good idea.
Now I know better…
After printing the core I installed an additional plugin to OctoPrint (DisplayLayerProgress) that led to printing in slow motion.
After seeing the calibration cube below, it was obvious even to me that something went terribly wrong…
In fact the Raspberry Pi 1 is too slow to feed the printer with commands fast enough.
Now that I found it out myself I find posts telling NOT to use OctpPrint on a Raspberry Pi 1 everywhere.
Again, not Octoprint is to blame, but me.
The remaing parts I printed directly from the SD card.
I also had the problem several other people reported that the bearing of the core clamp was not touching the tube.
I had to tighten the bolt real hard to remove any play. But the range to correct squareness is very limited, basically not existing.
Anyhow I could setup my MPCNC Primo completely and it moved for the first time today.
The bottomline of all this is to say thank you to Ryan to give me good reason to reprint the core.
(And I mean it, no sarcasm this time!)
It is good that a solution is found that avoids having to try tweaked parts of any kind.
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Man that test cube looks as if you drew it with a 3D pen.
How big is yours? Mine is 1m as well and I don’t have supports. Should I have supports?
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The table is 110x90 cm.
Although the tubes are stainless steel 25mm with 2mm walls you can really feel the flex. I did not expect that initially. And the tubes really bend down when the Burly gantry moved. So I decided do add supports at least for the longer tubes.
I noticed that the bolt (and nut) are rotating from vibration. Does this just need a little tightening? The bearing does not rotate with z rods, rotates freely
What is your specific tube length for the x-sides?
Do you think the flex is really noticable when the machine is operating? I’m planning to have a long x, the outer sides 1124mm, with 2mm thick walls. Could I ask you for a favor?? I’m going to assemble tomorrow, but wonder if you could do a small test? I don’t want supports, so I’d rather reduce the x if necessary. If you run the gantry from side to side in the x-direction, would the gantry sag when you are in the middle, closer to the bed?
Edit: shoot… I’ll assemble it with the current length and see how it goes. If the sag is noticeable and impacting the functionality, I’ll simply shrink it. Right now the table is sized to this specific length, with two ledges under the feet in the y direction.
Yup, they should all be in contact, with equal tension. Test by spinning with your fingers, all 4 should be in contact and take a little force to rotate.
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