Z-axis threaded rod question

Hi,
I have started to build my Vertex printer and i have now gotten to the part when i am supposed to screw in the threaded rod into the follower nut, but it feels like its more resistance the it should be.
How hard is it supposed to be too screw in the threaded rod into the Iglidur follower nut?
I have to use a plier to even be able to turn the rod, and i doubt the stepper motor will be able to turn the rod with that amount of resistance.

It should not be that hard to screw in the threaded rod; Mine had resistance but I did it by hand (gloved thumb and finger). If you remove the rod from the nut, does the nut inside show mashed threads? Maybe it was cross-threaded or a wrong part slipped into your kit? I might try using a tap to re-cut the threads but this might not be recommended by Velleman.

The threads in the upper part of the nut are messed up, i took out the nut and screwed the rod from the bottom of the piece and it went smoothly until i came halfway in.

Then I suggest to re-tap the threads. A real cutting tap tool would be best, but if you don’t have this, it may be possible to craft one. It may not work, but it may save having to get a replacement nut from Velleman. If you look closely at any self-tapping screw that is commonly used these days, there is usually one or more angled cuts at the tip, parallel with the screw and across the first few threads. You could use a hack-saw to cut 4 or 5 such slots around one end of the threaded rod, creating some sharp corners. Screw this into the nut from the bottom, and the messed threads should be cut clean, or at least pushed back towards their proper position. The notched end of the rod could then be hidden in the motor coupler. If this doesn’t work, a replacement nut would be required.

I have rethreaded the nut and it appears to run smoothly now, one side of the nut was 1mm smaller the the other side of the nut.
Thanks for the help Bert I really appreciate it.