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Re: Z-axix linear bearings

Posted: January 25th, 2017, 7:41 am
by Neotko
Umm I can prepare a file. It was an extrusion from the dxf files. This weekend I upload all.

Re: Z-axix linear bearings

Posted: January 25th, 2017, 8:08 am
by antiklesys
Much appreciated, thank you!

Also, I think one alternative for people willing to perform this mod is to use threaded rods. Those can be found for less than 1€ in local hardware stores and then can be cut down with a dremel or similar tools. The 1€ price is for 1mt of that. It's true it won't be "high precision stuff" but I believe they'll still be able to do the job.

Re: Z-axix linear bearings

Posted: January 25th, 2017, 9:48 am
by Izzy
I believe the beauty of Gudo's LH and RH threads is that it acts as a turnbuckle so that you may tighten it slightly to level/ debuckle your plate if it is uneven from one side to the other.
That the reason I have gone for turnbuckles so that I can not only add stiffness to the plate but can also even it out a little, (obviously only a little pressure due to the plastic parts)

Re: Z-axix linear bearings

Posted: January 25th, 2017, 11:09 am
by gudo
antiklesys wrote:Much appreciated, thank you!

Also, I think one alternative for people willing to perform this mod is to use threaded rods. Those can be found for less than 1€ in local hardware stores and then can be cut down with a dremel or similar tools. The 1€ price is for 1mt of that. It's true it won't be "high precision stuff" but I believe they'll still be able to do the job.
Hi all
Hi antiklesys,
Ofc you can do that, that would work too ! ;-)
As Izzy said,
I believe the beauty of Gudo's LH and RH threads is that it acts as a turnbuckle so that you may tighten it slightly to level/ debuckle your plate if it is uneven from one side to the other.
The advantage of using rod end arms with reversed threads is that it allows fine adjustment of the horizontal level of the bed
By turning them in one direction or the other they are either extended or shortened from the length already determined in the assembly instructions
So for the must, it's advisable to use a bubble level tool
After installing the bed system, remove the glass, just unscrew the heat plate (care to not hurt PCB),
- First check that the printer is well horizontal
- adjust the bed plate while using the bubble level tool, so you can be sure the plate is parallel to the horizontal plane of the machine.
- Then reassemble the heat plate and of course it will be necessary to recalibrate the bed with respect to the nozzle

Image

Re: Z-axix linear bearings

Posted: January 25th, 2017, 12:04 pm
by MTVDNA
Do you still have the same print area? It almost looks as though the print head would collide with those rods..?

Re: Z-axix linear bearings

Posted: January 25th, 2017, 1:19 pm
by antiklesys
MTVDNA wrote:Do you still have the same print area? It almost looks as though the print head would collide with those rods..?
Head won't be able to collide on the rods, the closest thing which may collide with the rods are the X/Y motors actually

Re: Z-axix linear bearings

Posted: January 25th, 2017, 1:25 pm
by Neotko
antiklesys wrote:
MTVDNA wrote:Do you still have the same print area? It almost looks as though the print head would collide with those rods..?
Head won't be able to collide on the rods, the closest thing which may collide with the rods are the X/Y motors actually
Actually I had to change the height a bit for my umo+ because my 40x40x20 fan cap actually did hit the rods. But that's all I know. I don't use um2fans (and will never use).

Re: Z-axix linear bearings

Posted: January 25th, 2017, 1:34 pm
by antiklesys
Neotko wrote:
antiklesys wrote:
MTVDNA wrote:Do you still have the same print area? It almost looks as though the print head would collide with those rods..?
Head won't be able to collide on the rods, the closest thing which may collide with the rods are the X/Y motors actually
Actually I had to change the height a bit for my umo+ because my 40x40x20 fan cap actually did hit the rods. But that's all I know. I don't use um2fans (and will never use).
Good point, I actually forgot about the fans! :lol: :-D

Re: Z-axix linear bearings

Posted: January 25th, 2017, 2:32 pm
by gudo
MTVDNA wrote:Do you still have the same print area? It almost looks as though the print head would collide with those rods..?
Hi MTVDNA !
Good point !
You're right ! the printing area is a bit smaller, for very large prints that will pose problem, especialy on back right area
personaly I never had this need but it's important to mention it, I will warning that on the youmagine sharing, thanks for noticed it !

Re: Z-axix linear bearings

Posted: January 25th, 2017, 2:36 pm
by Neotko
It could be very very easy to make the rods a bit lower. Ofc it might dampen the vibrations a bit less, but for me it works quite nicely

Re: Z-axix linear bearings

Posted: January 26th, 2017, 5:35 am
by nilrog
Here is another failed print. The first one after converting to GT2 belts. I did a fair share of movement and cleaning of the Z-axis but that did not help.

You can see the small irregularity on the one remaining pillar. The other one snapped of very easily. And that one you cannot easily break again so layer bonding is not an issue.
IMG_0575.JPG
(there is something with this forum and images...it rotates them for some reason)

Re: Z-axix linear bearings

Posted: January 26th, 2017, 7:41 am
by antiklesys
That could not be only with the Z but also an extruder issue

Re: Z-axix linear bearings

Posted: January 26th, 2017, 7:46 am
by nilrog
If this were an extruder issue it would happen in more places. This only happens on this particular level, and on all prints regardless of how they look. The print is perfect both below and above.

Re: Z-axix linear bearings

Posted: January 26th, 2017, 7:46 am
by Izzy
Have a quick check of the feeders knurling for dust and or particulates, and try dropping your speed a little (45mm/s), and you could add a little lubricating oil to help through the Bowden tube.

Re: Z-axix linear bearings

Posted: January 26th, 2017, 8:01 am
by nilrog
Again, all these parts are perfect.

But the bearings are not...at any place on the rods...if you move them up and then down (just as the bed does when you start printing) the friction increases greatly after ~10 mm.

I can print any part and unless a miracle happens you will see the same problem at the same level.