Like I said in your thread. I am trying to solve the problem not tell people to go print other parts.
A friend of mine printed me the parts. He hasn’t done the test yet. He’ll print it next week.
As soon as I know anything new, I’ll let you know.
I measured the height of the core. It’s exactly 140mm high.
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Man, you really are setting the bar for asking help! I think these are the most detailed photos and feedback I’ve seen, at least in recent memory!
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Perfect thank you.
There does seem to be a difference in my J parts to my C parts, but I had a print issue and had to restart them, so hopefully I can test first thing tomorrow.
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Well bummer, sure enough it does not fit. I then triple checked my 25.4mm parts, fit perfectly.
Hmmm, I will have to go over the model with a fine toothed comb. I have no idea what could be different. I do know how to fix it but I am going to spend a little time looking for a fixed number that should be a variable. I don’t like thinking some models need an offset and others don’t and none of the other parts have an offset and fit perfectly. There must be a missing variable. Odd that the parts are a different size, you would think if I was missing a variable something would be the same but it is not.
Sorry thinking out loud.
Working on it now.
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Frick…I found it.
The bolt holes are supposed to be on that dotted line, instead they are locked onto a sketch behind it. That makes them 0.2mm off on each side, and those holes spread the part at an angle so that is compounded. So the 3rd bearing is right, and we checked all those dimensions many times. Turns out the core holes are just too wide.
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Oops. That’s a bummer.
I’m actually surprised it doesn’t happen more often though. I know I am not detail oriented enough to catch these things.
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Yeah I have enough trouble thinking in 2D 3D with mid point constraints and fixed or parametric my brain would be the melted puddle
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Well it is funky and not an easy catch. there are two bolt holes defined. It is anchored on that line (center of the bearing my main parametric sketch), the other is defining it left to right (dependent on the Z axis sketch). Normally it is never that close together (90 degree planes is pretty common). This is just a special case…such a flub.
The second hole is actually defined differently from the first even. So in this sketch I screwed up twice. Same location overall though. The good part is the only other flub is the bearing stand off, should be defined by this hole, and was defined by the same point. I must not have turned off that other sketch in the middle of it all.
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Ouch. Well, glad you found it!
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I guess the clamps are designed parametric to the core?
Because my analysis of the clamps shows the same result, you should update these as well.
Yes everything is parametric.
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Incidentally, cap head screws may have clearance issues on the Z axis. You might need 4 hex bolts for the bolts on the core adjacent to the Z axis, or you might need to grind down the heads on those cap head bolts.
Edit: I said 4 bolts, I meant 8. Or maybe some will squeak by. Test fit and you will find out.
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@vicious1
Hi There,
just downloaded the new version, but now i miss the Core_F_Primo in the package ?!
Could you tell us when its completly updatet ?
Thx
edit: The missing file ( core-f-primo-v1.stl)
Can be downloaded on PrusaPrinters
@vicious1 I’m in the last stages of my 25mm build. I was seeing some play as well but was able to eliminate it by tightening the clamps, but I worry that I might have overtightened them.
Should I reprint the core parts? I’d need to get some more PLA first.
Also, what’s the benefit of the new trucks you just released?
Thanks!
All the new core files are up. I just double checked.
If it is snug, leave it alone, if you break a part, reprint them all.
at the print in Cura on layer high line 485 (CORE) hes getting out of control,
hope thats not bad
cause its my last filament
hey, guys,
I have successfully crossed the Alps and am now back here 
Thank you very much that you have taken up this topic so intensively!
The new core and the clamps were printed to me in the meantime. Yesterday I installed and tested the parts directly.
default assembly
I have assembled everything, the rail is still about 1mm away from the stock.
altered assembly
By this method I could bring the situation a lot closer. The rails X- and Y-axis were only slightly wobbling.
After I installed the core, it has probably stretched so far that the core only wobbles a little bit. At the moment I would say it should fit.
Do you have any other experiences with the new version?
It would be interesting to know if the adjustment only works for me, all other rail clamps are working fine and can be adjusted too much like for the trucks.
I will continue to assemble the MPCNC, if I can still help just let me know.
Cheers Chris
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