MK3 Kit, Y-Axis not completely flat
Hello, I am assembling a new MK3 Kit and in Chapter 2 Step 10, the geometry of the assembled platform fails me, there is an error of one millimeter. I have loosened all the screws several times and retightened them diagonally and the measurement difference continues.
I attached some photos in which I found that aluminum extrusions and mounting plates differ their measurements with respect to each other.
There are two profiles that measure approximately 18.1mm and two that measure 17.6mm. In addition, just as those who measure more are aligned on the same diagonal of the platform, makes the error is added (0.5mm + 0.5mm) which results in 1mm that is just the millimeter that I take the structure .
Thanks and best regards
Re: MK3 Kit, Y-Axis not completely flat
One more picture...
Re: MK3 Kit, Y-Axis not completely flat
Joaquin, Over the holiday break, I read through all the running commentary for the online version of the assembly steps and a few other of our MK3 brethren have noted they had to bore out these and a few other 3mm holes a bit more (0.5 mm?) to ease the tolerances. When final tightening occurs, this would allow the beams to drift enough and become planar once tightened. I recommend reading up on those threads and see what the current consensus is.
Re: MK3 Kit, Y-Axis not completely flat
Thanks Martin, in my manual Online Spanish version the comments did not come, but in the English version I have already seen them.
http://manual.prusa3d.com/Guide/2.+Y-axis+assembly/507?lang=en
What you say may be a solution, but none of the comments speaks of having done it, only as a possible theoretical solution.
What I do not understand is with a multitude of people that the same thing happens to them, and a clear design flaw in not admitting tolerances, which makes the PRUSA support that does not answer? Do not answer my mails, do not answer this post, and do not respond to the 16 comments request for help.
Re: MK3 Kit, Y-Axis not completely flat
Yes, their latency in addressing this obvious design flaw is a bit concerting. I just saw in a thread around here that someone actually clamped down the back extruded aluminum bars while pushing down on the front and then tightening the screws. No obvious concessions to enlarging the bolt holes. In this manner, they were able to get the frame planar. Albeit under stress.
Did you also see the comment in the instructions that advised to check the flatness of each extruded part horizontally on all for faces as well as on the top & bottom. The front and rear plates should also be flat too.
If you do see things out of plane, then I'd get ahold of PR support as well with photos of the bad pieces. I've definitely heard good feedback from other forum users with this approach. Giving the support guys evidence of something faulty really can't be ignored.
Good luck!
Re: MK3 Kit, Y-Axis not completely flat
He has answered the PRUSA support telling me to try to enlarge the holes to give more slack, but it does not work either. I have tried to press the structure while I tighten and neither.
Finally I have asked PRUSA to send me the new set of pieces, because honestly I can not waste more time with this. I hope they react quickly, because at the moment I am quite disappointed. Let's see how everything ends ...