Hi Bram
I've sorted this successfully, and wrote it up here:?
The forum link has discussion.
Note to self - upload the article to my website.
Chris Parks has an alternate method, which involves drilling through the adjusting block to allow oil to the screw.
Here is the transcript of my article:??
Servicing the Hammer K3 blade adjust
Sooner or later your blade adjuster on your K3 will become stiff and require two hands to turn the wheel. It may take a few years, but it will occur, and then you will need to lube the mechanism.
I know Chris Parks has a modification he has made, but I barely knew where the mechanism was, let alone had the courage to do this.
About a year ago I called in Felder to sort it out, as the local guys are good folk and very responsive. They came out, but I was not that happy with the result. The adjuster felt stiffer still than when original. And it cost me a couple of hundred bucks. The adjuster was so stiff in recent weeks, that even two hands was a struggle.
This weekend I decided to do it myself. The result was very successful, and I wanted to pass on what I did.
First you have to open up access to the winder. Remove the switch panel ...

Slide away the box ...

The thread with the blade lowered all the way ...

The thread with the blade fully up ...

After cleaning all the dust inside the cabinet, and then blowing out any remaining dust, a silicon spray was directed at the thread. This was repeated several times with the winder in-and-out. It made little if any difference.
When Felder were here a year ago, the technician used lithium grease. So I sprayed this on, again repeatedly, and wound the handle in-and-out. A little improvement, but not much better than Felder achieved.
Finally I added a bunch of graphite to the thread, and wound it in-and-out. This made a big difference. And the more I wound the wheel, the better it got. I am not sure if the graphite helped clear any remaining gunk, or whether it was the lubricant needed. I returned to the wheel later, and it was now winding up (down is always easy) very comfortably with one hand.
Those who have done this might chip in her with anything else to be done or tried.
I did add some graphite to the slider, and this really smoothed it.

Regards from Perth
Derek