Jump to content
Ultimaker Community of 3D Printing Experts
Sign in to follow this  

Z section guides

Recommended Posts

Looks like I've hit this common problem of the Z guides being about 3-4 mm too narrow for the guide rods. I forced them in but the tabs on the left side of the table popped out. I just about got them back in but the plates either side of the z nut are loose. I noticed that this is a common issue so why hasn't the hole spacing being altered on the top and bottom frame sections by the Ultimaker team? :x

Any ideas on how to firm up the framework around the Z nut guys?


UK England

Share this post

Link to post
Share on other sites

Yes the shaft centres are 3mm misaligned.

I dont know exactly why this was done, but my best guess is that they like the z carridge to stretch horizontally

to give it some preload on the bearings to be stable. You can see this because the left side of the Z carridge is flexible and has been designed to flex outwards to be able to fit to the shafts (which are 3mm wider than the bearings in the Z carridge).

The area around the nut has been made intentionally so that the bronze "nut" can move about, if you dont do that, what happens is that the lead screw will wobble the whole z axis carridge about, because its pretty wonky by the time its been coupled to the Z motor. So dont fix the bronze "Z nut" because it will just make your table wobble as it goes up and down.

It doesnt really matter that its loose in there, because gravity is keeping the table down anyway, and the table only goes down during printing. If it were having to do direction reverals, that would be a big problem. But it doesnt..so.

I do admit though, that im my opinion the z carridge design can be improved alot. Its not very solid generally

and could do with beefing up. This is one major reason behind layer misalignment on tall prints. I have seen some

people bolting on stuff to the flexible LHS of the carridge to stiffen it up.

Its not great, but there are a half dozen things to improve before you need to start worring about the z carridge.


Share this post

Link to post
Share on other sites

The Z screw is indeed misaligned a bit. We discovered this a few weeks ago, but on normal sized printers it doesn't cause any real problems. I think it's the result from the drawings being done in Illustrator instead of a CAD tool.

As snowygrouch already pointed out, it's very important that the bronze "nut" is lose. The leadscrew we use is never properly centered (it's almost impossible to create them perfectly centered) if you fix this firmly in the platform you will get ridges that exactly match the thread pitch.

Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

  • Our picks

    • Ultimaker Cura | a new interface
      We're not only trying to always make Ultimaker Cura better with the usual new features and improvements we build, but we're also trying to make it more pleasant to operate. The interface was the focus for the upcoming release, from which we would already like to present you the first glance. 
        • Like
      • 117 replies
    • "Back To The Future" using Generative Design & Investment Casting
      Designing for light-weight parts is becoming more important, and I’m a firm believer in the need to produce lighter weight, less over-engineered parts for the future. This is for sustainability reasons because we need to be using less raw materials and, in things like transportation, it impacts the energy usage of the product during it’s service life.
        • Like
      • 12 replies

Important Information

Welcome to the Ultimaker Community of 3D printing experts. Visit the following links to read more about our Terms of Use or our Privacy Policy. Thank you!