New K8800, same problem!

Hi there,
(English is not my native language)

after a lot of issues with my K8800 I sent it in for RMA support.
They fixed the problems, but the machine got wrecked in shipping back to me, therefor I recieved a complete new K8800 from Velleman.
Say what you want, that’s not something every brand does. Kudos for this excellent service.

Now, with more knowledge about the printer then the first time I built it, I started building this afternoon.

After completing the entire assembly manual (which is very good with pictures and video I might add) I had high hopes for the machine.

Now, after lubing the rods and balls. Loading the filament en hoping for the best… No dice :frowning:

This K8800 does the éxact same thing as the first one! Unfortunatly that must mean that I’m doing something wrong, because the chance of both machines having thesame defective part is slim to none.

The issue:
After the entire circus of calibration and loading filament I start the print. It calibrates again (sort of) and goes to the position in the back of the printer. But this machine also let’s go one of the rods when going to that position.
See video:

I tried and did the following:

  • I tightened the rods so hard, that I broke one of my tools to do so
  • I cleaned the standing rods with Isopropanol and lubed them slightly with sewing machine oil making sure it’s not to much
  • The ‘stoppers’ are tightened
  • If I tap the bed, the red light flashes on the side
  • I reviewed the belts, they are as tight as I can get them
  • The tie-wraps are tightened real hard, I snapped 2 while installing them.
  • The printbed sticker has been cut of at the edges


  • I also followed all the calibration steps a few times
  • Auto home works fine
  • Saved the calibration too
  • Yes, the machine is leveled on the table

I really hope someone can help me with my issues for I am desperate now :frowning:
Thanx in advance!!

Hello again, I have been fiddling around with the machine today and I think I got it to work.
I undid all the screws at the bottom of the machine, well at least the screws that hold the rods where the magnet things slide up and down.

Now, the printhead doesnt ‘park’ outside the printbed and printing starts normally.

At least, I thought it was…

The printhead has some issues with heating I think. If I add new filament in my first K8800 the filament always extrudes while it’s loading. This one doesn’t.
Then, as soon as I start printing it makes the right moves, but no filament comes out. If I look at the top of the machine I can clearly see the filament being pushed into the guiding tube. But after 3 or 4 pushes, you can see the filament shooting back a bit. Paired with a fair bit of noise.

I am using thesame filament as with the first device so that’s not the issue.
It is almost as if the head doesnt get hot enough to melt the filament. I will try some more tomorrow, but any suggestions would be appreciated.

Okay I am back again, this time to tell everyone I got it to work.

The tube that guides the filament to the printhead wasnt correctly mounted into the printhead.
I put it in, but didn’t put it in deep enough.

After repeating the steps I got it to work and the machine has been printing almost non stop for 4 days now.

I loosened the vertical rods where the sliders move so that’s not tightened anymore, but that seems to work great. No errors anymore.

Nice to hear that You have solved the calibration problem. Nice work :+1:
Thanks for the feedback about your troubleshooting.
We wish you a lot of printing pleasure

With your last comment we will take into account in the investigation of “calibration problem” and can mention this under § calibratin issues

Best Regards,
Velleman Support